iprs000138
10.3205/iprs000138
urn:nbn:de:0183-iprs0001381
Original Article
Current aspects of salivary gland tumors – a systematic review of the literature
Aktuelle Aspekte der Speicheldrüsentumore – eine systematische Recherche der Literatur
Galdirs
Galdirs
Theresa Marie
TM
Martin Luther University Halle-Wittenberg, University hospital, Department of Oral and Maxillofacial Plastic Surgery, Ernst-Grube-Str. 40, 06120 Halle/Saale, Germany, Phone: +49 345 557 5246, Fax: +49 345 557 5291Martin Luther University Halle-Wittenberg, University hospital, Department of Oral and Maxillofacial Plastic Surgery, Halle, Germany
Theresa_Galdirs@gmx.de
author
Kappler
Kappler
Matthias
M
Martin Luther University Halle-Wittenberg, University hospital, Department of Oral and Maxillofacial Plastic Surgery, Halle, Germany
author
Reich
Reich
Waldemar
W
Martin Luther University Halle-Wittenberg, University hospital, Department of Oral and Maxillofacial Plastic Surgery, Halle, Germany
author
Eckert
Eckert
Alexander W.
AW
Martin Luther University Halle-Wittenberg, University hospital, Department of Oral and Maxillofacial Plastic Surgery, Halle, Germany
author
German Medical Science GMS Publishing House
Düsseldorf
610
salivary gland tumors
pleomorphic adenoma
adenoid cystic carcinoma
mucoepidermoid carcinoma
acinic cell carcinoma
Speicheldrüsentumore
pleomorphes Adenom
Adenoid zystisches Karzinom
Mukoepidermoidkarzinom
Azinuszellkarzinom
20190802
engl
This is an Open Access article distributed under the terms of the Creative Commons Attribution 4.0 License.
Dieser Artikel ist ein Open-Access-Artikel und steht unter den Lizenzbedingungen der Creative Commons Attribution 4.0 License (Namensnennung).
2193-8091
8
GMS Interdisciplinary Plastic and Reconstructive Surgery DGPW
GMS Interdiscip Plast Reconstr Surg DGPW
12
Ziel: Unser Review gibt eine aktuelle Übersicht über das Vorkommen der Speicheldrüsentumore. Näher dargelegt wurde dabei die divergierende Verteilung dieser Tumore bezogen auf Alter, Gender, anatomische Lokalisationen und spezifische geographische Ländereinteilungen. Ebenfalls visualisiert wurden die unterschiedlich auftretenden Entitäten bezogen auf Malignität und Benignität. Unsere Ausgangshypothese war, dass in verschiedenen Ländern die Verteilung der Tumorentitäten sowie die weiteren Charakteristika der Tumore (z.B. Alter und Gender der betroffenen Patienten, anatomische Lokalisation, Auftrittshäufigkeiten verschiedener Entitäten) variieren.Zusätzlich gibt unser Review eine Übersicht über die Veränderung der Tumorklassifikationen seit 1981 bis 2005. Material und Methoden: Für die systematische Literaturrecherche wurde die Datenbank PubMed.gov genutzt. Es wurde ein Fragenkatalog erstellt und Studien aus verschiedenen Ländern aufgenommen und analysiert.Ergebnisse: Durch das erste Auswahlverfahren wurden 141 Studien aus über 30 Ländern selektiert. Die somit erfasste Patientenkohorte betrug 25.826. Die Daten aus diesen Studien wurden bezüglich der verschiedenen Länder, Alter, Gender und dem Auftreten unterschiedlicher benigner und maligner Entitäten zusammengefasst und analysiert.Schlussfolgerung: Dieses Review verdeutlicht die starken lokalen Unterschiede im Auftreten der Speicheldrüsentumore. Unsere gesammelten Daten sollten als Grundstein für weitere Forschungen bezogen auf Therapieoptionen, Prognosen und Vorhersagen zu dem Auftreten von Speicheldrüsentumoren genommen werden.
Objectives: This study provides an up-to-date overview of the distribution of salivary gland tumors in relation to sex, land of treatment, localization of the tumor in the mouths, and benign/malignant disease of this type of tumor. We hypothesized that the distribution of patients with salivary gland tumors could vary according to country, gender, age and tumor specificity. In addition there is a comparison of the primary classification of salivary gland tumors from 1981 and the recent classification from 2005. Materials and methods: Data from the Medline database PubMed.gov and supplementary sources were used to conduct a systematic literature search. For this purpose, data from different studies were independently collected using a previously designed questionnaire. Results: The first section analyzes the general features of the relevant salivary gland tumors from 141 studies involving a total of 25,826 patients across 30 different countries in terms of gender and the occurrence of benign/malignant salivary gland tumors. These data were summarized and presented.Conclusion: This review offers an insight into the dramatic local differences with regard to salivary gland tumor occurrence as a stepping stone to further classify such data in order to derive effective therapy options, prognosis and widen the general understanding of the subject.
IntroductionSalivary gland tumors are a rare phenomenon. This heterogeneous group of pathologies encompasses approximately 3–5% of head and neck carcinomas, and only 0.5% of all malignant tumors match these types . The incidence of all salivary gland tumors varies between 0.3 to 4 per 100,000, population, with the highest identified among the Inuit , . The results of current studies focus on isolated characteristics of the salivary gland tumors (e.g., age and gender, therapy, localization, etc.) as opposed to a holistic view of salivary gland tumors, and therefore, they need to be summarized and visualized to be easily comparable in terms of the epidemiology, therapy, and prognosis. Some different reviews concerning salivary gland tumors have been published in the last two centuries , , , , , , , , , , , , , , , most of which discuss the entities or diagnostic or prognostic aspects and principal therapeutic strategies in detail. However, there is no research article that described an overview of the gender-specific distribution as well as country-specific differences for those tumors. Therefore, the purpose of this actual article is to present an up-to-date overview of the characteristics of salivary gland tumors through a literature review. This overview will detail the epidemiologic, gender, benign/malign and country-specific distributions of this tumor entities. Moreover, this work presents an inventory of the current state with regard to salivary gland tumors in general.
Material and methodsStudy selection criteria The literature search was carried out until January 2018, and includes articles dating back as far as 1981. The databases were searched for relevant studies using the key words “salivary gland tumors”, “pleomorphic adenoma”, “adenoid cystic carcinoma”, “mucoepidermoid carcinoma” and “acinic cell carcinoma”. As support, 3 textbooks and 1 medical doctoral thesis were used to complement the article. All the used sources are freely accessible. Studies eligible for inclusion in this analysis had to meet the following criteria: recent publications (between 1981 and 2018), statistically evaluable, multiple salivary gland tumor types, various geographic and anatomic locations, therapy analysis, prognosis with a focus on survival (disease-free survival, overall survival, relapse time, among others), case studies, clinico-pathological studies in hospitals, retrospective cohort studies in patients with salivary gland tumors and reviews. Two reviewers (TMG and AWE) independently carried out the study selection, data extraction, and quality assessment. The reviewers independently screened all records (titles and abstract) that were identified by the search strategy to select potentially eligible publications. Care has being taken to discard duplicated content, outdated and unrelated studies. Country-based statistics were derived from individual clinic data with a significant amount of patients only. Data extractionThe two reviewers independently extracted data from all eligible studies using a previously designed question catalogue. The following information was compiled: title of the publication, name of the journal, data source, name of the first author, year of publication, country, study design and characteristics of the study findings (age, sex, countries, prognosis), cancer type, cancer site, clinical and pathological tumor stage, type of treatment and survival analysis. Studies of all age groups were included in the analysis.Figure 1 shows a flow chart of the identified and included records. The detailed results of characteristics and parameters are presented as follows. As shown in Figure 1 , among thousands of published articles dealing with salivary gland tumors, a total of 51 sources were considered relevant for further investigation.
ResultsEpidemiological data Patient ages ranged from 2.5 to 92 years , , even though some studies focused on occurrences in children. The mean age ranged from 41.9 to 43 years , , correlating with a peak in the fifth decade of life . Benign tumors were more likely in younger patients aged 35.0±17.2 years and malignant tumors in older patients aged 48.8±18.2 . Depending on the country of origin, the distributions of salivary gland tumors differed between men and women. In China, the distribution of men/women was <![CDATA[1 : 0.9</PlainText></TextGroup> <TextLink reference="23"></TextLink>, and in Nigeria it was <TextGroup><PlainText>1 : 1.8</PlainText></TextGroup> <TextLink reference="19"></TextLink>. No special data were found for all salivary gland tumors, or specifically for tumors of minor salivary glands in Germany. Table 1 <ImgLink imgNo="1" imgType="table"/> shows the detailed gender distribution of different countries.</Pgraph><SubHeadline>Anatomical localization</SubHeadline><Pgraph>Between 60 and 84.2% of all tumors were to be found in the parotid glands <TextLink reference="6"></TextLink>, <TextLink reference="20"></TextLink>, but only 16% were in the submandibular glands. Tumors of the sublingual gland were rare, but all were malignant according to Luksic et al. <TextLink reference="24"></TextLink>. Malignant tumors are generally less common than benign tumors in the large salivary glands <TextLink reference="6"></TextLink>.</Pgraph><Pgraph>Minor salivary gland tumors were found in 24 to 39.3% of cases <TextLink reference="19"></TextLink>, <TextLink reference="20"></TextLink>. The palate was the most common site of minor salivary gland tumors in 33.3 to 67% of cases <TextLink reference="21"></TextLink>, <TextLink reference="25"></TextLink>, followed by the upper lip and buccal mucosa <TextLink reference="26"></TextLink>. A larger proportion of benign tumors were found in the palate of females (75.00%) compared with male patients (64.00%) <TextLink reference="7"></TextLink>.</Pgraph><SubHeadline>Diagnostic approaches</SubHeadline><Pgraph>Preoperative diagnostics are mainly based on imaging methods and pathological findings, especially fine-needle aspiration cytology (FNAC) <TextLink reference="2"></TextLink>.</Pgraph><Pgraph>Ultrasound, magnetic resonance imaging (MRI) and contrast-enhanced computed tomography (CT) are the most commonly used imaging modalities to evaluate salivary gland lesions <TextLink reference="27"></TextLink>.</Pgraph><Pgraph>Ultrasound remains the basic diagnostic imaging procedure, especially when occurring in parotid glands <TextLink reference="2"></TextLink>. As a low cost, non-invasive modality, ultrasound provides excellent localization of the tumor in the gland and enables differentiation from the cystic mass <TextLink reference="2"></TextLink>.</Pgraph><Pgraph>For lesions of the minor and sublingual salivary glands of the deep parotid lobe or of malignant neoplasia with suspected perineural invasion or bone infiltration, MRI is mandatory to evaluate the tumor extent, local invasion and perineural spread <TextLink reference="2"></TextLink>.</Pgraph><Pgraph>CT should be an alternative modality when MRI is not available. Certain carcinomas (for example, mucoepidermoid carcinoma, adenoid cystic carcinoma or acinic cell carcinoma) may lack significant contrast enhancement, leading to oversight or underestimation of the lesion <TextLink reference="2"></TextLink>.</Pgraph><SubHeadline>Tumor type</SubHeadline><Pgraph>In total, the evaluation included 9 studies on malignant salivary gland tumors and 22 on benign and malignant. In most studies, pleomorphic adenoma was most likely in benign tumors in approximately 42% of cases <TextLink reference="21"></TextLink>, <TextLink reference="28"></TextLink>. The three prevalent malignant salivary gland tumors are adenoid cystic carcinoma, mucoepidermoid carcinoma and acinic cell carcinoma <TextLink reference="29"></TextLink>. The distribution of tumor types broken down by countries is shown in Table 2 <ImgLink imgNo="2" imgType="table"/>. </Pgraph><Pgraph>Irregular margins, bony invasions, the presence of metastatic lymph nodes and perineural spread can all be signs of malignancy <TextLink reference="30"></TextLink>. Necrosis can also characterize malignancy <TextLink reference="31"></TextLink>.</Pgraph><SubHeadline>Distribution of malign and benign salivary gland tumors</SubHeadline><Pgraph>Examining all salivary gland tumors, the distribution of malignant and benign also differed, as shown in Table 3 <ImgLink imgNo="3" imgType="table"/>. The distribution also differed for minor and major salivary gland tumors. In Brazil, only 20% of all tumors were malignant <TextLink reference="32"></TextLink>, whereas this number was much higher in Nigeria, where 71.1% were diagnosed <TextLink reference="19"></TextLink>. We found no reliable studies or reviews from Germany because most of the data were from limited patient groups or were not properly itemized.</Pgraph><SubHeadline>Histologic entities of salivary gland tumors</SubHeadline><Pgraph>It has been difficult to categorize salivary gland tumors according to their clinical behavior. To retain the kind of tumors, Schwenzer/Grimm and Barnes published a differentiated WHO histological classification of tumors of salivary glands in 1981 <TextLink reference="33"></TextLink> and in 2005 <TextLink reference="34"></TextLink> (Table 4 <ImgLink imgNo="4" imgType="table"/>).</Pgraph><SubHeadline>Therapeutic aspects of salivary gland tumors</SubHeadline><Pgraph>Salivary gland carcinomas are tumors with a heterogeneous morphology that require distinctive surgical therapy <TextLink reference="2"></TextLink>. Surgical excision is the treatment of choice for resectable tumors <TextLink reference="2"></TextLink>. Chemotherapy for salivary gland tumors can be ineffective. Studies of newly targeted therapies have not offered significant benefits <TextLink reference="35"></TextLink>. Successes with chemotherapy alone and/or combinations with radiotherapy have been recorded for salivary duct carcinoma and carcinoma ex pleomorphic adenoma <TextLink reference="36"></TextLink>. Histologic grade is important for prognosis and therapy. Surgery remains the mainstay of treatment when negative margins can be achieved. Radiation improves locoregional control of tumors with high-risk features <TextLink reference="35"></TextLink>. In conclusion, more additive prognostic parameters are of great interest. This individual molecular signaling is further discussed in detail.</Pgraph></TextBlock>
<TextBlock linked="yes" name="Discussion">
<MainHeadline>Discussion</MainHeadline><Pgraph>With the aforementioned key words and generally available research mechanisms, e.g., PubMed.gov, more than 37,000 publications could be identified. At first glance, this seems to represent a unique treasure trove of data. However, applicable and valuable data were extracted by careful categorization and selection, which is necessary because articles that present a current overview of benign and malignant salivary gland tumors are missing. </Pgraph><Pgraph>Despite differing countries of origin, our work identified several similarities. For example, benign tumors were more common than malignant ones. The prevalent benign tumor was PA, and the prevalent malignant tumors were ACC and MEC <TextLink reference="5"></TextLink>, <TextLink reference="6"></TextLink>.</Pgraph><Pgraph>The majority of tumors in the minor salivary glands and in the sublingual gland were malignant <TextLink reference="7"></TextLink>, <TextLink reference="11"></TextLink>.</Pgraph><Pgraph>The significance of the evaluated literature is indicated, but it differs for every country and every tumor entity. In some countries, the studies include thousands of patients, whereas in other countries, the studies include only up to a few hundred patients. The studies are often of one single institute and do not evaluate the whole country. Tumor research also differs. Most research concerns the most prevalent tumors (e.g., PA), but more attention should be focused on malignant ones because a permanent and frequently extended overview about therapy, prognosis and the distribution of different features (e.g., gender, age, proportion of malign and benign) is currently needed for improved diagnosis and treatment in the future. This could also provide insights into the formulation of risk groups to receive recurring preventive examinations. In all reviewed publications, however, none showed a correlation with cultural standings, living circumstances or habits (e.g., smoking, alcoholism). </Pgraph><Pgraph>To the best of our knowledge, this is the largest research article of salivary gland tumors in terms of gender distribution. Moreover, this work primarily presents a scientific summary of the worldwide distribution of benign and malignant salivary gland tumors, their demographics, the distribution of multiple entities in the form of a mini review, as well as the clinical features (e.g., symptoms, therapy, prognosis) of general salivary gland tumors. To our knowledge, this is the first article to contain all of these characteristics, thus providing a specific view perspective.</Pgraph><Pgraph>By comparing these results with squamous cell carcinoma (SCC) of the oral cavity, for which such questions have been undergoing assessments with great success for almost two decades, the research activity for malignant salivary gland tumors is in its infancy.</Pgraph><Pgraph>This article reveals an apparent lack of research in Germany. A thorough analysis from a maxillofacial surgical standpoint is also missing. A next step will thus be to perform a monocentric study of this topic, particularly because prognostic assertions of benign and malignant forms (PA, ACC, MEC, AciCC) will be of great clinical importance. The University of Halle (Saale) is currently evaluating its diagnosed tumor entities over the last <TextGroup><PlainText>25 years</PlainText></TextGroup> to provide this missing information. However, the results must be combined with other university findings to generate a holistic view of different tumor entities in Germany.</Pgraph></TextBlock>
<TextBlock linked="yes" name="Notes">
<MainHeadline>Notes</MainHeadline><SubHeadline>Acknowledgements</SubHeadline><Pgraph>We thank our colleagues from the Department of Oral and Maxillofacial Plastic Surgery for contributing to this study and for their continuous support.</Pgraph><SubHeadline>Competing interests</SubHeadline><Pgraph>The authors declare that they have no competing interests.</Pgraph></TextBlock>
<References linked="yes">
<Reference refNo="1">
<RefAuthor>Lawal AO</RefAuthor>
<RefAuthor>Adisa AO</RefAuthor>
<RefAuthor>Kolude B</RefAuthor>
<RefAuthor>Adeyemi BF</RefAuthor>
<RefTitle>Malignant salivary gland tumours of the head and neck region: a single institutions review</RefTitle>
<RefYear>2015</RefYear>
<RefJournal>Pan Afr Med J</RefJournal>
<RefPage>121</RefPage>
<RefTotal>Lawal AO, Adisa AO, Kolude B, Adeyemi BF. Malignant salivary gland tumours of the head and neck region: a single institutions review. Pan Afr Med J. 2015 Feb 12;20:121. DOI: 10.11604/pamj.2015.20.121.3458</RefTotal>
<RefLink>http://dx.doi.org/10.11604/pamj.2015.20.121.3458</RefLink>
</Reference>
<Reference refNo="2">
<RefAuthor>Ettl T</RefAuthor>
<RefAuthor>Schwarz-Furlan S</RefAuthor>
<RefAuthor>Gosau M</RefAuthor>
<RefAuthor>Reichert TE</RefAuthor>
<RefTitle>Salivary gland carcinomas</RefTitle>
<RefYear>2012</RefYear>
<RefJournal>Oral Maxillofac Surg</RefJournal>
<RefPage>267-83</RefPage>
<RefTotal>Ettl T, Schwarz-Furlan S, Gosau M, Reichert TE. Salivary gland carcinomas. Oral Maxillofac Surg. 2012 Sep;16(3):267-83. DOI: 10.1007/s10006-012-0350-9</RefTotal>
<RefLink>http://dx.doi.org/10.1007/s10006-012-0350-9</RefLink>
</Reference>
<Reference refNo="3">
<RefAuthor>Bradley PJ</RefAuthor>
<RefTitle>Primary malignant parotid epithelial neoplasm: nodal metastases and management</RefTitle>
<RefYear>2015</RefYear>
<RefJournal>Curr Opin Otolaryngol Head Neck Surg</RefJournal>
<RefPage>91-8</RefPage>
<RefTotal>Bradley PJ. Primary malignant parotid epithelial neoplasm: nodal metastases and management. Curr Opin Otolaryngol Head Neck Surg. 2015 Apr;23(2):91-8. DOI: 10.1097/MOO.0000000000000139</RefTotal>
<RefLink>http://dx.doi.org/10.1097/MOO.0000000000000139</RefLink>
</Reference>
<Reference refNo="4">
<RefAuthor>Dahl A</RefAuthor>
<RefAuthor>Teegen J</RefAuthor>
<RefAuthor>Altevogt P</RefAuthor>
<RefAuthor>Löning T</RefAuthor>
<RefAuthor>Schumacher U</RefAuthor>
<RefTitle>Glycoconjugate expression in adenoid cystic carcinoma of the salivary glands: up-regulation of L1 predicts fatal prognosis</RefTitle>
<RefYear>2011</RefYear>
<RefJournal>Histopathology</RefJournal>
<RefPage>299-307</RefPage>
<RefTotal>Dahl A, Teegen J, Altevogt P, Löning T, Schumacher U. Glycoconjugate expression in adenoid cystic carcinoma of the salivary glands: up-regulation of L1 predicts fatal prognosis. Histopathology. 2011 Aug;59(2):299-307. DOI: 10.1111/j.1365-2559.2011.03895.x</RefTotal>
<RefLink>http://dx.doi.org/10.1111/j.1365-2559.2011.03895.x</RefLink>
</Reference>
<Reference refNo="5">
<RefAuthor>Zaman S</RefAuthor>
<RefAuthor>Majid S</RefAuthor>
<RefAuthor>Chugtai O</RefAuthor>
<RefAuthor>Hussain M</RefAuthor>
<RefAuthor>Nasir M</RefAuthor>
<RefTitle>Salivary gland tumours: a review of 91 cases</RefTitle>
<RefYear>2014</RefYear>
<RefJournal>J Ayub Med Coll Abbottabad</RefJournal>
<RefPage>361-3</RefPage>
<RefTotal>Zaman S, Majid S, Chugtai O, Hussain M, Nasir M. Salivary gland tumours: a review of 91 cases. J Ayub Med Coll Abbottabad. 2014 Jul-Sep;26(3):361-3.</RefTotal>
</Reference>
<Reference refNo="6">
<RefAuthor>Trenkić Božinović M</RefAuthor>
<RefAuthor>Krasić D</RefAuthor>
<RefAuthor>Katić V</RefAuthor>
<RefAuthor>Krstić M</RefAuthor>
<RefTitle>A retrospective review of 139 major and minor salivary gland tumors</RefTitle>
<RefYear>2015</RefYear>
<RefJournal>Med Glas (Zenica)</RefJournal>
<RefPage>73-8</RefPage>
<RefTotal>Trenkić Božinović M, Krasić D, Katić V, Krstić M. A retrospective review of 139 major and minor salivary gland tumors. Med Glas (Zenica). 2015 Feb;12(1):73-8. </RefTotal>
</Reference>
<Reference refNo="7">
<RefAuthor>Gbotolorun OM</RefAuthor>
<RefAuthor>Arotiba GT</RefAuthor>
<RefAuthor>Effiom OA</RefAuthor>
<RefAuthor>Omitola OG</RefAuthor>
<RefTitle>Minor salivary gland tumours in a Nigerian hospital: a retrospective review of 146 cases</RefTitle>
<RefYear>2008</RefYear>
<RefJournal>Odontostomatol Trop</RefJournal>
<RefPage>17-23</RefPage>
<RefTotal>Gbotolorun OM, Arotiba GT, Effiom OA, Omitola OG. Minor salivary gland tumours in a Nigerian hospital: a retrospective review of 146 cases. Odontostomatol Trop. 2008 Sep;31(123):17-23.</RefTotal>
</Reference>
<Reference refNo="8">
<RefAuthor>Mosunjac MB</RefAuthor>
<RefAuthor>Siddiqui MT</RefAuthor>
<RefAuthor>Tadros T</RefAuthor>
<RefTitle>Acinic cell carcinoma-papillary cystic variant. Pitfalls of fine needle aspiration diagnosis: study of five cases and review of literature</RefTitle>
<RefYear>2009</RefYear>
<RefJournal>Cytopathology</RefJournal>
<RefPage>96-102</RefPage>
<RefTotal>Mosunjac MB, Siddiqui MT, Tadros T. Acinic cell carcinoma-papillary cystic variant. Pitfalls of fine needle aspiration diagnosis: study of five cases and review of literature. Cytopathology. 2009 Apr;20(2):96-102. DOI: 10.1111/j.1365-2303.2007.00480.x</RefTotal>
<RefLink>http://dx.doi.org/10.1111/j.1365-2303.2007.00480.x</RefLink>
</Reference>
<Reference refNo="9">
<RefAuthor>Jaber MA</RefAuthor>
<RefTitle>Intraoral minor salivary gland tumors: a review of 75 cases in a Libyan population</RefTitle>
<RefYear>2006</RefYear>
<RefJournal>Int J Oral Maxillofac Surg</RefJournal>
<RefPage>150-4</RefPage>
<RefTotal>Jaber MA. Intraoral minor salivary gland tumors: a review of 75 cases in a Libyan population. Int J Oral Maxillofac Surg. 2006 Feb;35(2):150-4. DOI: 10.1016/j.ijom.2005.07.006</RefTotal>
<RefLink>http://dx.doi.org/10.1016/j.ijom.2005.07.006</RefLink>
</Reference>
<Reference refNo="10">
<RefAuthor>Lau R</RefAuthor>
<RefAuthor>Fernández-Coello A</RefAuthor>
<RefAuthor>Vidal-Sarró N</RefAuthor>
<RefAuthor>Céspedes D</RefAuthor>
<RefAuthor>Camins A</RefAuthor>
<RefAuthor>Taberna M</RefAuthor>
<RefAuthor>Gabarrós A</RefAuthor>
<RefTitle>Brain metastasis of carcinoma ex pleomorphic adenoma of the parotid gland: case report and review of the literature</RefTitle>
<RefYear>2017</RefYear>
<RefJournal>Acta Neurochir (Wien)</RefJournal>
<RefPage>459-63</RefPage>
<RefTotal>Lau R, Fernández-Coello A, Vidal-Sarró N, Céspedes D, Camins A, Taberna M, Gabarrós A. Brain metastasis of carcinoma ex pleomorphic adenoma of the parotid gland: case report and review of the literature. Acta Neurochir (Wien). 2017 Mar;159(3):459-63. DOI: 10.1007/s00701-017-3080-9.</RefTotal>
<RefLink>http://dx.doi.org/10.1007/s00701-017-3080-9.</RefLink>
</Reference>
<Reference refNo="11">
<RefAuthor>Eveson JW</RefAuthor>
<RefAuthor>Cawson RA</RefAuthor>
<RefTitle>Salivary gland tumours. A review of 2410 cases with particular reference to histological types, site, age and sex distribution</RefTitle>
<RefYear>1985</RefYear>
<RefJournal>J Pathol</RefJournal>
<RefPage>51-8</RefPage>
<RefTotal>Eveson JW, Cawson RA. Salivary gland tumours. A review of 2410 cases with particular reference to histological types, site, age and sex distribution. J Pathol. 1985 May;146(1):51-8. DOI: 10.1002/path.1711460106</RefTotal>
<RefLink>http://dx.doi.org/10.1002/path.1711460106</RefLink>
</Reference>
<Reference refNo="12">
<RefAuthor>Fomete B</RefAuthor>
<RefAuthor>Adeosun OO</RefAuthor>
<RefAuthor>Awelimobor DI</RefAuthor>
<RefAuthor>Olayemie L</RefAuthor>
<RefTitle>Recurrent pleomorphic adenoma of the upper lip: case report and review of the literature</RefTitle>
<RefYear>2015</RefYear>
<RefJournal>Niger J Med</RefJournal>
<RefPage>277-80</RefPage>
<RefTotal>Fomete B, Adeosun OO, Awelimobor DI, Olayemie L. Recurrent pleomorphic adenoma of the upper lip: case report and review of the literature. Niger J Med. 2015 Jul-Sep;24(3):277-80.</RefTotal>
</Reference>
<Reference refNo="13">
<RefAuthor>Abu-Ghanem Y</RefAuthor>
<RefAuthor>Mizrachi A</RefAuthor>
<RefAuthor>Popovtzer A</RefAuthor>
<RefAuthor>Abu-Ghanem N</RefAuthor>
<RefAuthor>Feinmesser R</RefAuthor>
<RefTitle>Recurrent pleomorphic adenoma of the parotid gland: Institutional experience and review of the literature</RefTitle>
<RefYear>2016</RefYear>
<RefJournal>J Surg Oncol</RefJournal>
<RefPage>714-8</RefPage>
<RefTotal>Abu-Ghanem Y, Mizrachi A, Popovtzer A, Abu-Ghanem N, Feinmesser R. Recurrent pleomorphic adenoma of the parotid gland: Institutional experience and review of the literature. J Surg Oncol. 2016 Nov;114(6):714-8. DOI: 10.1002/jso.24392</RefTotal>
<RefLink>http://dx.doi.org/10.1002/jso.24392</RefLink>
</Reference>
<Reference refNo="14">
<RefAuthor>Knight J</RefAuthor>
<RefAuthor>Ratnasingham K</RefAuthor>
<RefTitle>Metastasising pleomorphic adenoma: Systematic review</RefTitle>
<RefYear>2015</RefYear>
<RefJournal>Int J Surg</RefJournal>
<RefPage>137-45</RefPage>
<RefTotal>Knight J, Ratnasingham K. Metastasising pleomorphic adenoma: Systematic review. Int J Surg. 2015 Jul;19:137-45. DOI: 10.1016/j.ijsu.2015.04.084</RefTotal>
<RefLink>http://dx.doi.org/10.1016/j.ijsu.2015.04.084</RefLink>
</Reference>
<Reference refNo="15">
<RefAuthor>Gondivkar SM</RefAuthor>
<RefAuthor>Gadbail AR</RefAuthor>
<RefAuthor>Chole R</RefAuthor>
<RefAuthor>Parikh RV</RefAuthor>
<RefTitle>Adenoid cystic carcinoma: a rare clinical entity and literature review</RefTitle>
<RefYear>2011</RefYear>
<RefJournal>Oral Oncol</RefJournal>
<RefPage>231-6</RefPage>
<RefTotal>Gondivkar SM, Gadbail AR, Chole R, Parikh RV. Adenoid cystic carcinoma: a rare clinical entity and literature review. Oral Oncol. 2011 Apr;47(4):231-6. DOI: 10.1016/j.oraloncology.2011.01.009</RefTotal>
<RefLink>http://dx.doi.org/10.1016/j.oraloncology.2011.01.009</RefLink>
</Reference>
<Reference refNo="16">
<RefAuthor>Sur RK</RefAuthor>
<RefAuthor>Donde B</RefAuthor>
<RefAuthor>Levin V</RefAuthor>
<RefAuthor>Pacella J</RefAuthor>
<RefAuthor>Kotzen J</RefAuthor>
<RefAuthor>Cooper K</RefAuthor>
<RefAuthor>Hale M</RefAuthor>
<RefTitle>Adenoid cystic carcinoma of the salivary glands: a review of 10 years</RefTitle>
<RefYear>1997</RefYear>
<RefJournal>Laryngoscope</RefJournal>
<RefPage>1276-80</RefPage>
<RefTotal>Sur RK, Donde B, Levin V, Pacella J, Kotzen J, Cooper K, Hale M. Adenoid cystic carcinoma of the salivary glands: a review of 10 years. Laryngoscope. 1997 Sep;107(9):1276-80. DOI: 10.1097/00005537-199709000-00022</RefTotal>
<RefLink>http://dx.doi.org/10.1097/00005537-199709000-00022</RefLink>
</Reference>
<Reference refNo="17">
<RefAuthor>Chundru NS</RefAuthor>
<RefAuthor>Amudala R</RefAuthor>
<RefAuthor>Thankappan P</RefAuthor>
<RefAuthor>Nagaraju CD</RefAuthor>
<RefTitle>Adenoid cystic carcinoma of palate: A case report and review of literature</RefTitle>
<RefYear>2013</RefYear>
<RefJournal>Dent Res J (Isfahan)</RefJournal>
<RefPage>274-8</RefPage>
<RefTotal>Chundru NS, Amudala R, Thankappan P, Nagaraju CD. Adenoid cystic carcinoma of palate: A case report and review of literature. Dent Res J (Isfahan). 2013 Mar;10(2):274-8.</RefTotal>
</Reference>
<Reference refNo="18">
<RefAuthor>Rapidis AD</RefAuthor>
<RefAuthor>Givalos N</RefAuthor>
<RefAuthor>Gakiopoulou H</RefAuthor>
<RefAuthor>Stavrianos SD</RefAuthor>
<RefAuthor>Faratzis G</RefAuthor>
<RefAuthor>Lagogiannis GA</RefAuthor>
<RefAuthor>Katsilieris I</RefAuthor>
<RefAuthor>Patsouris E</RefAuthor>
<RefTitle>Mucoepidermoid carcinoma of the salivary glands. Review of the literature and clinicopathological analysis of 18 patients</RefTitle>
<RefYear>2007</RefYear>
<RefJournal>Oral Oncol</RefJournal>
<RefPage>130-6</RefPage>
<RefTotal>Rapidis AD, Givalos N, Gakiopoulou H, Stavrianos SD, Faratzis G, Lagogiannis GA, Katsilieris I, Patsouris E. Mucoepidermoid carcinoma of the salivary glands. Review of the literature and clinicopathological analysis of 18 patients. Oral Oncol. 2007 Feb;43(2):130-6. Epub 2006 Jul 20. DOI: 10.1016/j.oraloncology.2006.03.001</RefTotal>
<RefLink>http://dx.doi.org/10.1016/j.oraloncology.2006.03.001</RefLink>
</Reference>
<Reference refNo="19">
<RefAuthor>Fomete B</RefAuthor>
<RefAuthor>Adebayo ET</RefAuthor>
<RefAuthor>Ononiwu CN</RefAuthor>
<RefTitle>Management of salivary gland tumors in a Nigerian tertiary institution</RefTitle>
<RefYear>2015</RefYear>
<RefJournal>Ann Afr Med</RefJournal>
<RefPage>148-54</RefPage>
<RefTotal>Fomete B, Adebayo ET, Ononiwu CN. Management of salivary gland tumors in a Nigerian tertiary institution. Ann Afr Med. 2015 Jul-Sep;14(3):148-54. DOI: 10.4103/1596-3519.152071</RefTotal>
<RefLink>http://dx.doi.org/10.4103/1596-3519.152071</RefLink>
</Reference>
<Reference refNo="20">
<RefAuthor>Moatemri R</RefAuthor>
<RefAuthor>Belajouza H</RefAuthor>
<RefAuthor>Farroukh U</RefAuthor>
<RefAuthor>Ommezzine M</RefAuthor>
<RefAuthor>Slama A</RefAuthor>
<RefAuthor>Ayachi S</RefAuthor>
<RefAuthor>Khochtali H</RefAuthor>
<RefAuthor>Bakir A</RefAuthor>
<RefTitle></RefTitle>
<RefYear>2008</RefYear>
<RefJournal>Rev Stomatol Chir Maxillofac</RefJournal>
<RefPage>148-52</RefPage>
<RefTotal>Moatemri R, Belajouza H, Farroukh U, Ommezzine M, Slama A, Ayachi S, Khochtali H, Bakir A. [Epidemiological profile of salivary-glands tumors in a Tunisian teaching hospital]. Rev Stomatol Chir Maxillofac. 2008 Jun;109(3):148-52. DOI: 10.1016/j.stomax.2008.04.001</RefTotal>
<RefLink>http://dx.doi.org/10.1016/j.stomax.2008.04.001</RefLink>
</Reference>
<Reference refNo="21">
<RefAuthor>Adebiyi KE</RefAuthor>
<RefAuthor>Emmanuel MM</RefAuthor>
<RefTitle>Neoplastic Salivary Gland Lesions:A Retrospective Analysis of 135 Cases from Lagos State University Teaching Hospital, Ikeja, Lagos, Nigeria</RefTitle>
<RefYear>2014</RefYear>
<RefJournal>West Afr J Med</RefJournal>
<RefPage>206-10</RefPage>
<RefTotal>Adebiyi KE, Emmanuel MM. Neoplastic Salivary Gland Lesions:A Retrospective Analysis of 135 Cases from Lagos State University Teaching Hospital, Ikeja, Lagos, Nigeria. West Afr J Med. 2014 Jul-Sep;33(3):206-10.</RefTotal>
</Reference>
<Reference refNo="22">
<RefAuthor>Jaafari-Ashkavandi Z</RefAuthor>
<RefAuthor>Ashraf MJ</RefAuthor>
<RefAuthor>Afandak N</RefAuthor>
<RefTitle>A clinico-pathologic study of 82 intraoral minor salivary gland tumors</RefTitle>
<RefYear>2011</RefYear>
<RefJournal>Iran Red Crescent Med J</RefJournal>
<RefPage>674-7</RefPage>
<RefTotal>Jaafari-Ashkavandi Z, Ashraf MJ, Afandak N. A clinico-pathologic study of 82 intraoral minor salivary gland tumors. Iran Red Crescent Med J. 2011 Sep;13(9):674-7.</RefTotal>
</Reference>
<Reference refNo="23">
<RefAuthor>Tian Z</RefAuthor>
<RefAuthor>Li L</RefAuthor>
<RefAuthor>Wang L</RefAuthor>
<RefAuthor>Hu Y</RefAuthor>
<RefAuthor>Li J</RefAuthor>
<RefTitle>Salivary gland neoplasms in oral and maxillofacial regions: a 23-year retrospective study of 6982 cases in an eastern Chinese population</RefTitle>
<RefYear>2010</RefYear>
<RefJournal>Int J Oral Maxillofac Surg</RefJournal>
<RefPage>235-42</RefPage>
<RefTotal>Tian Z, Li L, Wang L, Hu Y, Li J. Salivary gland neoplasms in oral and maxillofacial regions: a 23-year retrospective study of 6982 cases in an eastern Chinese population. Int J Oral Maxillofac Surg. 2010 Mar;39(3):235-42. DOI: 10.1016/j.ijom.2009.10.016</RefTotal>
<RefLink>http://dx.doi.org/10.1016/j.ijom.2009.10.016</RefLink>
</Reference>
<Reference refNo="24">
<RefAuthor>Lukšić I</RefAuthor>
<RefAuthor>Virag M</RefAuthor>
<RefAuthor>Manojlović S</RefAuthor>
<RefAuthor>Macan D</RefAuthor>
<RefTitle>Salivary gland tumours: 25 years of experience from a single institution in Croatia</RefTitle>
<RefYear>2012</RefYear>
<RefJournal>J Craniomaxillofac Surg</RefJournal>
<RefPage>e75-81</RefPage>
<RefTotal>Lukšić I, Virag M, Manojlović S, Macan D. Salivary gland tumours: 25 years of experience from a single institution in Croatia. J Craniomaxillofac Surg. 2012 Apr;40(3):e75-81. DOI: 10.1016/j.jcms.2011.05.002</RefTotal>
<RefLink>http://dx.doi.org/10.1016/j.jcms.2011.05.002</RefLink>
</Reference>
<Reference refNo="26">
<RefAuthor>Waldron CA</RefAuthor>
<RefAuthor>el-Mofty SK</RefAuthor>
<RefAuthor>Gnepp DR</RefAuthor>
<RefTitle>Tumors of the intraoral minor salivary glands: a demographic and histologic study of 426 cases</RefTitle>
<RefYear>1988</RefYear>
<RefJournal>Oral Surg Oral Med Oral Pathol</RefJournal>
<RefPage>323-33</RefPage>
<RefTotal>Waldron CA, el-Mofty SK, Gnepp DR. Tumors of the intraoral minor salivary glands: a demographic and histologic study of 426 cases. Oral Surg Oral Med Oral Pathol. 1988 Sep;66(3):323-33. DOI: 10.1016/0030-4220(88)90240-X</RefTotal>
<RefLink>http://dx.doi.org/10.1016/0030-4220(88)90240-X</RefLink>
</Reference>
<Reference refNo="25">
<RefAuthor>Ito FA</RefAuthor>
<RefAuthor>Ito K</RefAuthor>
<RefAuthor>Vargas PA</RefAuthor>
<RefAuthor>de Almeida OP</RefAuthor>
<RefAuthor>Lopes MA</RefAuthor>
<RefTitle>Salivary gland tumors in a Brazilian population: a retrospective study of 496 cases</RefTitle>
<RefYear>2005</RefYear>
<RefJournal>Int J Oral Maxillofac Surg</RefJournal>
<RefPage>533-6</RefPage>
<RefTotal>Ito FA, Ito K, Vargas PA, de Almeida OP, Lopes MA. Salivary gland tumors in a Brazilian population: a retrospective study of 496 cases. Int J Oral Maxillofac Surg. 2005 Jul;34(5):533-6. DOI: 10.1016/j.ijom.2005.02.005</RefTotal>
<RefLink>http://dx.doi.org/10.1016/j.ijom.2005.02.005</RefLink>
</Reference>
<Reference refNo="27">
<RefAuthor>Razfar A</RefAuthor>
<RefAuthor>Heron DE</RefAuthor>
<RefAuthor>Branstetter BF 4th</RefAuthor>
<RefAuthor>Seethala RR</RefAuthor>
<RefAuthor>Ferris RL</RefAuthor>
<RefTitle>Positron emission tomography-computed tomography adds to the management of salivary gland malignancies</RefTitle>
<RefYear>2010</RefYear>
<RefJournal>Laryngoscope</RefJournal>
<RefPage>734-8</RefPage>
<RefTotal>Razfar A, Heron DE, Branstetter BF 4th, Seethala RR, Ferris RL. Positron emission tomography-computed tomography adds to the management of salivary gland malignancies. Laryngoscope. 2010 Apr;120(4):734-8. DOI: 10.1002/lary.20829</RefTotal>
<RefLink>http://dx.doi.org/10.1002/lary.20829</RefLink>
</Reference>
<Reference refNo="28">
<RefAuthor>Buchner A</RefAuthor>
<RefAuthor>Merrell PW</RefAuthor>
<RefAuthor>Carpenter WM</RefAuthor>
<RefTitle>Relative frequency of intra-oral minor salivary gland tumors: a study of 380 cases from northern California and comparison to reports from other parts of the world</RefTitle>
<RefYear>2007</RefYear>
<RefJournal>J Oral Pathol Med</RefJournal>
<RefPage>207-14</RefPage>
<RefTotal>Buchner A, Merrell PW, Carpenter WM. Relative frequency of intra-oral minor salivary gland tumors: a study of 380 cases from northern California and comparison to reports from other parts of the world. J Oral Pathol Med. 2007 Apr;36(4):207-14. DOI: 10.1111/j.1600-0714.2007.00522.x</RefTotal>
<RefLink>http://dx.doi.org/10.1111/j.1600-0714.2007.00522.x</RefLink>
</Reference>
<Reference refNo="29">
<RefAuthor>Mărgăritescu C</RefAuthor>
<RefAuthor>Munteanu MC</RefAuthor>
<RefAuthor>Niţulescu NC</RefAuthor>
<RefAuthor>Cionca L</RefAuthor>
<RefAuthor>Cotoi OS</RefAuthor>
<RefAuthor>Paskova G</RefAuthor>
<RefTitle>Acinic cell carcinoma of the salivary glands: an immunohistochemical study of angiogenesis in 12 cases</RefTitle>
<RefYear>2013</RefYear>
<RefJournal>Rom J Morphol Embryol</RefJournal>
<RefPage>275-84</RefPage>
<RefTotal>Mărgăritescu C, Munteanu MC, Niţulescu NC, Cionca L, Cotoi OS, Paskova G. Acinic cell carcinoma of the salivary glands: an immunohistochemical study of angiogenesis in 12 cases. Rom J Morphol Embryol. 2013;54(2):275-84.</RefTotal>
</Reference>
<Reference refNo="37">
<RefAuthor>Garden AS</RefAuthor>
<RefAuthor>Weber RS</RefAuthor>
<RefAuthor>Ang KK</RefAuthor>
<RefAuthor>Morrison WH</RefAuthor>
<RefAuthor>Matre J</RefAuthor>
<RefAuthor>Peters LJ</RefAuthor>
<RefTitle>Postoperative radiation therapy for malignant tumors of minor salivary glands. Outcome and patterns of failure</RefTitle>
<RefYear>1994</RefYear>
<RefJournal>Cancer</RefJournal>
<RefPage>2563-9</RefPage>
<RefTotal>Garden AS, Weber RS, Ang KK, Morrison WH, Matre J, Peters LJ. Postoperative radiation therapy for malignant tumors of minor salivary glands. Outcome and patterns of failure. Cancer. 1994 May 15;73(10):2563-9. </RefTotal>
</Reference>
<Reference refNo="38">
<RefAuthor>Li YN</RefAuthor>
<RefAuthor>He ZX</RefAuthor>
<RefAuthor>Liu LK</RefAuthor>
<RefAuthor>He HW</RefAuthor>
<RefTitle></RefTitle>
<RefYear>2004</RefYear>
<RefJournal>Hua Xi Kou Qiang Yi Xue Za Zhi</RefJournal>
<RefPage>204-6</RefPage>
<RefTotal>Li YN, He ZX, Liu LK, He HW. [A retrospective study on 615 cases of minor salivary gland tumors]. Hua Xi Kou Qiang Yi Xue Za Zhi. 2004 Jun;22(3):204-6.</RefTotal>
</Reference>
<Reference refNo="39">
<RefAuthor>Hessling JT</RefAuthor>
<RefTitle></RefTitle>
<RefYear>2014</RefYear>
<RefBookTitle>Eine retrospektive Analyse von 18 Jahren aus der Klinik und Poliklinik für Mund-, Kiefer- und plastische Gesichtschirurgie der Universität Bonn im Vergleich zur aktuellen Literatur [Habilitationsschrift]</RefBookTitle>
<RefPage></RefPage>
<RefTotal>Hessling JT. Eine retrospektive Analyse von 18 Jahren aus der Klinik und Poliklinik für Mund-, Kiefer- und plastische Gesichtschirurgie der Universität Bonn im Vergleich zur aktuellen Literatur [Habilitationsschrift]. Bonn: Universität Bonn; 2014.</RefTotal>
</Reference>
<Reference refNo="40">
<RefAuthor>Luukkaa H</RefAuthor>
<RefAuthor>Klemi P</RefAuthor>
<RefAuthor>Leivo I</RefAuthor>
<RefAuthor>Koivunen P</RefAuthor>
<RefAuthor>Laranne J</RefAuthor>
<RefAuthor>Mäkitie A</RefAuthor>
<RefAuthor>Virtaniemi J</RefAuthor>
<RefAuthor>Hinkka S</RefAuthor>
<RefAuthor>Grénman R</RefAuthor>
<RefTitle>Salivary gland cancer in Finland 1991--96: an evaluation of 237 cases</RefTitle>
<RefYear>2005</RefYear>
<RefJournal>Acta Otolaryngol</RefJournal>
<RefPage>207-14</RefPage>
<RefTotal>Luukkaa H, Klemi P, Leivo I, Koivunen P, Laranne J, Mäkitie A, Virtaniemi J, Hinkka S, Grénman R. Salivary gland cancer in Finland 1991--96: an evaluation of 237 cases. Acta Otolaryngol. 2005 Feb;125(2):207-14. DOI: 10.1080/00016480510003174</RefTotal>
<RefLink>http://dx.doi.org/10.1080/00016480510003174</RefLink>
</Reference>
<Reference refNo="41">
<RefAuthor>Bjørndal K</RefAuthor>
<RefAuthor>Krogdahl A</RefAuthor>
<RefAuthor>Therkildsen MH</RefAuthor>
<RefAuthor>Overgaard J</RefAuthor>
<RefAuthor>Johansen J</RefAuthor>
<RefAuthor>Kristensen CA</RefAuthor>
<RefAuthor>Homøe P</RefAuthor>
<RefAuthor>Sørensen CH</RefAuthor>
<RefAuthor>Andersen E</RefAuthor>
<RefAuthor>Bundgaard T</RefAuthor>
<RefAuthor>Primdahl H</RefAuthor>
<RefAuthor>Lambertsen K</RefAuthor>
<RefAuthor>Andersen LJ</RefAuthor>
<RefAuthor>Godballe C</RefAuthor>
<RefTitle>Salivary gland carcinoma in Denmark 1990-2005: a national study of incidence, site and histology. Results of the Danish Head and Neck Cancer Group (DAHANCA)</RefTitle>
<RefYear>2011</RefYear>
<RefJournal>Oral Oncol</RefJournal>
<RefPage>677-82</RefPage>
<RefTotal>Bjørndal K, Krogdahl A, Therkildsen MH, Overgaard J, Johansen J, Kristensen CA, Homøe P, Sørensen CH, Andersen E, Bundgaard T, Primdahl H, Lambertsen K, Andersen LJ, Godballe C. Salivary gland carcinoma in Denmark 1990-2005: a national study of incidence, site and histology. Results of the Danish Head and Neck Cancer Group (DAHANCA). Oral Oncol. 2011 Jul;47(7):677-82. DOI: 10.1016/j.oraloncology.2011.04.020</RefTotal>
<RefLink>http://dx.doi.org/10.1016/j.oraloncology.2011.04.020</RefLink>
</Reference>
<Reference refNo="42">
<RefAuthor>Aravind RM</RefAuthor>
<RefAuthor>Narayanan NS</RefAuthor>
<RefAuthor>Ravishankar KS</RefAuthor>
<RefAuthor>Babu NG</RefAuthor>
<RefTitle>Acinic cell carcinoma of buccal mucosa: An unusual presentation</RefTitle>
<RefYear>2015</RefYear>
<RefJournal>J Cancer Res Ther</RefJournal>
<RefPage>931-3</RefPage>
<RefTotal>Aravind RM, Narayanan NS, Ravishankar KS, Babu NG. Acinic cell carcinoma of buccal mucosa: An unusual presentation. J Cancer Res Ther. 2015 Oct-Dec;11(4):931-3. DOI: 10.4103/0973-1482.157352</RefTotal>
<RefLink>http://dx.doi.org/10.4103/0973-1482.157352</RefLink>
</Reference>
<Reference refNo="43">
<RefAuthor>Subhashraj K</RefAuthor>
<RefTitle>Salivary gland tumors: a single institution experience in India</RefTitle>
<RefYear>2008</RefYear>
<RefJournal>Br J Oral Maxillofac Surg</RefJournal>
<RefPage>635-8</RefPage>
<RefTotal>Subhashraj K. Salivary gland tumors: a single institution experience in India. Br J Oral Maxillofac Surg. 2008 Dec;46(8):635-8. DOI: 10.1016/j.bjoms.2008.03.020</RefTotal>
<RefLink>http://dx.doi.org/10.1016/j.bjoms.2008.03.020</RefLink>
</Reference>
<Reference refNo="32">
<RefAuthor>Vargas PA</RefAuthor>
<RefAuthor>Gerhard R</RefAuthor>
<RefAuthor>Araújo Filho VJ</RefAuthor>
<RefAuthor>de Castro IV</RefAuthor>
<RefTitle>Salivary gland tumors in a Brazilian population: a retrospective study of 124 cases</RefTitle>
<RefYear>2002</RefYear>
<RefJournal>Rev Hosp Clin Fac Med Sao Paulo</RefJournal>
<RefPage>271-6</RefPage>
<RefTotal>Vargas PA, Gerhard R, Araújo Filho VJ, de Castro IV. Salivary gland tumors in a Brazilian population: a retrospective study of 124 cases. Rev Hosp Clin Fac Med Sao Paulo. 2002 Nov-Dec;57(6):271-6. DOI: 10.1590/S0041-87812002000600005</RefTotal>
<RefLink>http://dx.doi.org/10.1590/S0041-87812002000600005</RefLink>
</Reference>
<Reference refNo="44">
<RefAuthor>Tilakaratne WM</RefAuthor>
<RefAuthor>Jayasooriya PR</RefAuthor>
<RefAuthor>Tennakoon TM</RefAuthor>
<RefAuthor>Saku T</RefAuthor>
<RefTitle>Epithelial salivary tumors in Sri Lanka: a retrospective study of 713 cases</RefTitle>
<RefYear>2009</RefYear>
<RefJournal>Oral Surg Oral Med Oral Pathol Oral Radiol Endod</RefJournal>
<RefPage>90-8</RefPage>
<RefTotal>Tilakaratne WM, Jayasooriya PR, Tennakoon TM, Saku T. Epithelial salivary tumors in Sri Lanka: a retrospective study of 713 cases. Oral Surg Oral Med Oral Pathol Oral Radiol Endod. 2009 Jul;108(1):90-8. DOI: 10.1016/j.tripleo.2009.01.026</RefTotal>
<RefLink>http://dx.doi.org/10.1016/j.tripleo.2009.01.026</RefLink>
</Reference>
<Reference refNo="45">
<RefAuthor>Erovic BM</RefAuthor>
<RefAuthor>Shah MD</RefAuthor>
<RefAuthor>Bruch G</RefAuthor>
<RefAuthor>Johnston M</RefAuthor>
<RefAuthor>Kim J</RefAuthor>
<RefAuthor>O’Sullivan B</RefAuthor>
<RefAuthor>Perez-Ordonez B</RefAuthor>
<RefAuthor>Weinreb I</RefAuthor>
<RefAuthor>Atenafu EG</RefAuthor>
<RefAuthor>de Almeida JR</RefAuthor>
<RefAuthor>Gullane PJ</RefAuthor>
<RefAuthor>Brown D</RefAuthor>
<RefAuthor>Gilbert RW</RefAuthor>
<RefAuthor>Irish JC</RefAuthor>
<RefAuthor>Goldstein DP</RefAuthor>
<RefTitle>Outcome analysis of 215 patients with parotid gland tumors: a retrospective cohort analysis</RefTitle>
<RefYear>2015</RefYear>
<RefJournal>J Otolaryngol Head Neck Surg</RefJournal>
<RefPage>43</RefPage>
<RefTotal>Erovic BM, Shah MD, Bruch G, Johnston M, Kim J, O’Sullivan B, Perez-Ordonez B, Weinreb I, Atenafu EG, de Almeida JR, Gullane PJ, Brown D, Gilbert RW, Irish JC, Goldstein DP. Outcome analysis of 215 patients with parotid gland tumors: a retrospective cohort analysis. J Otolaryngol Head Neck Surg. 2015 Oct 29;44:43. DOI: 10.1186/s40463-015-0097-z</RefTotal>
<RefLink>http://dx.doi.org/10.1186/s40463-015-0097-z</RefLink>
</Reference>
<Reference refNo="46">
<RefAuthor>Mesolella M</RefAuthor>
<RefAuthor>Iengo M</RefAuthor>
<RefAuthor>Testa D</RefAuthor>
<RefAuthor>DI Lullo AM</RefAuthor>
<RefAuthor>Salzano G</RefAuthor>
<RefAuthor>Salzano FA</RefAuthor>
<RefTitle>Mucoepidermoid carcinoma of the base of tongue</RefTitle>
<RefYear>2015</RefYear>
<RefJournal>Acta Otorhinolaryngol Ital</RefJournal>
<RefPage>58-61</RefPage>
<RefTotal>Mesolella M, Iengo M, Testa D, DI Lullo AM, Salzano G, Salzano FA. Mucoepidermoid carcinoma of the base of tongue. Acta Otorhinolaryngol Ital. 2015 Feb;35(1):58-61. </RefTotal>
</Reference>
<Reference refNo="47">
<RefAuthor>Altinay S</RefAuthor>
<RefAuthor>Taskın U</RefAuthor>
<RefAuthor>Sar M</RefAuthor>
<RefAuthor>Aydın S</RefAuthor>
<RefAuthor>Oktay MF</RefAuthor>
<RefTitle>Histopathological diversity in parotidectomy materials in Turkish population: clinicopathologic analysis and demographic features of 136 cases in a tertiary care hospital</RefTitle>
<RefYear>2014</RefYear>
<RefJournal>Asian Pac J Cancer Prev</RefJournal>
<RefPage>5701-7</RefPage>
<RefTotal>Altinay S, Taskın U, Sar M, Aydın S, Oktay MF. Histopathological diversity in parotidectomy materials in Turkish population: clinicopathologic analysis and demographic features of 136 cases in a tertiary care hospital. Asian Pac J Cancer Prev. 2014;15(14):5701-7. DOI: 10.7314/APJCP.2014.15.14.5701</RefTotal>
<RefLink>http://dx.doi.org/10.7314/APJCP.2014.15.14.5701</RefLink>
</Reference>
<Reference refNo="48">
<RefAuthor>Cha W</RefAuthor>
<RefAuthor>Kim MS</RefAuthor>
<RefAuthor>Ahn JC</RefAuthor>
<RefAuthor>Cho SW</RefAuthor>
<RefAuthor>Sunwoo W</RefAuthor>
<RefAuthor>Song CM</RefAuthor>
<RefAuthor>Kwon TK</RefAuthor>
<RefAuthor>Sung MW</RefAuthor>
<RefAuthor>Kim KH</RefAuthor>
<RefTitle>Clinical analysis of acinic cell carcinoma in parotid gland</RefTitle>
<RefYear>2011</RefYear>
<RefJournal>Clin Exp Otorhinolaryngol</RefJournal>
<RefPage>188-92</RefPage>
<RefTotal>Cha W, Kim MS, Ahn JC, Cho SW, Sunwoo W, Song CM, Kwon TK, Sung MW, Kim KH. Clinical analysis of acinic cell carcinoma in parotid gland. Clin Exp Otorhinolaryngol. 2011 Dec;4(4):188-92. DOI: 10.3342/ceo.2011.4.4.188</RefTotal>
<RefLink>http://dx.doi.org/10.3342/ceo.2011.4.4.188</RefLink>
</Reference>
<Reference refNo="49">
<RefAuthor>Rosero DS</RefAuthor>
<RefAuthor>Alvarez R</RefAuthor>
<RefAuthor>Gambó P</RefAuthor>
<RefAuthor>Alastuey M</RefAuthor>
<RefAuthor>Valero A</RefAuthor>
<RefAuthor>Torrecilla N</RefAuthor>
<RefAuthor>Roche AB</RefAuthor>
<RefAuthor>Simón S</RefAuthor>
<RefTitle>Acinic Cell Carcinoma of the Parotid Gland with Four Morphological Features</RefTitle>
<RefYear>2016</RefYear>
<RefJournal>Iran J Pathol</RefJournal>
<RefPage>181-5</RefPage>
<RefTotal>Rosero DS, Alvarez R, Gambó P, Alastuey M, Valero A, Torrecilla N, Roche AB, Simón S. Acinic Cell Carcinoma of the Parotid Gland with Four Morphological Features. Iran J Pathol. 2016 Spring;11(2):181-5.</RefTotal>
</Reference>
<Reference refNo="50">
<RefAuthor>Tuffin JR</RefAuthor>
<RefAuthor>Daniel F</RefAuthor>
<RefAuthor>Davies AS</RefAuthor>
<RefAuthor>Tyrrell CJ</RefAuthor>
<RefTitle>Acinic cell carcinoma – Plymouth's experience with postoperative radical radiotherapy</RefTitle>
<RefYear>1989</RefYear>
<RefJournal>Br J Oral Maxillofac Surg</RefJournal>
<RefPage>186-91</RefPage>
<RefTotal>Tuffin JR, Daniel F, Davies AS, Tyrrell CJ. Acinic cell carcinoma – Plymouth's experience with postoperative radical radiotherapy. Br J Oral Maxillofac Surg. 1989 Jun;27(3):186-91. DOI: 10.1016/0266-4356(89)90142-3</RefTotal>
<RefLink>http://dx.doi.org/10.1016/0266-4356(89)90142-3</RefLink>
</Reference>
<Reference refNo="30">
<RefAuthor>Wierzbicka M</RefAuthor>
<RefAuthor>Kopeć T</RefAuthor>
<RefAuthor>Szyfter W</RefAuthor>
<RefAuthor>Kereiakes T</RefAuthor>
<RefAuthor>Bem G</RefAuthor>
<RefTitle>The presence of facial nerve weakness on diagnosis of a parotid gland malignant process</RefTitle>
<RefYear>2012</RefYear>
<RefJournal>Eur Arch Otorhinolaryngol</RefJournal>
<RefPage>1177-82</RefPage>
<RefTotal>Wierzbicka M, Kopeć T, Szyfter W, Kereiakes T, Bem G. The presence of facial nerve weakness on diagnosis of a parotid gland malignant process. Eur Arch Otorhinolaryngol. 2012 Apr;269(4):1177-82. DOI: 10.1007/s00405-011-1882-6</RefTotal>
<RefLink>http://dx.doi.org/10.1007/s00405-011-1882-6</RefLink>
</Reference>
<Reference refNo="31">
<RefAuthor>Zbären P</RefAuthor>
<RefAuthor>Schüpbach J</RefAuthor>
<RefAuthor>Nuyens M</RefAuthor>
<RefAuthor>Stauffer E</RefAuthor>
<RefAuthor>Greiner R</RefAuthor>
<RefAuthor>Häusler R</RefAuthor>
<RefTitle>Carcinoma of the parotid gland</RefTitle>
<RefYear>2003</RefYear>
<RefJournal>Am J Surg</RefJournal>
<RefPage>57-62</RefPage>
<RefTotal>Zbären P, Schüpbach J, Nuyens M, Stauffer E, Greiner R, Häusler R. Carcinoma of the parotid gland. Am J Surg. 2003 Jul;186(1):57-62. DOI: 10.1016/S0002-9610(03)00105-3</RefTotal>
<RefLink>http://dx.doi.org/10.1016/S0002-9610(03)00105-3</RefLink>
</Reference>
<Reference refNo="51">
<RefAuthor>Mejía-Velázquez CP</RefAuthor>
<RefAuthor>Durán-Padilla MA</RefAuthor>
<RefAuthor>Gómez-Apo E</RefAuthor>
<RefAuthor>Quezada-Rivera D</RefAuthor>
<RefAuthor>Gaitán-Cepeda LA</RefAuthor>
<RefTitle>Tumors of the salivary gland in Mexicans. A retrospective study of 360 cases</RefTitle>
<RefYear>2012</RefYear>
<RefJournal>Med Oral Patol Oral Cir Bucal</RefJournal>
<RefPage>e183-9</RefPage>
<RefTotal>Mejía-Velázquez CP, Durán-Padilla MA, Gómez-Apo E, Quezada-Rivera D, Gaitán-Cepeda LA. Tumors of the salivary gland in Mexicans. A retrospective study of 360 cases. Med Oral Patol Oral Cir Bucal. 2012 Mar 1;17(2):e183-9. DOI: 10.4317/medoral.17434</RefTotal>
<RefLink>http://dx.doi.org/10.4317/medoral.17434</RefLink>
</Reference>
<Reference refNo="33">
<RefAuthor>Schwenzer N</RefAuthor>
<RefAuthor>Grimm G</RefAuthor>
<RefTitle></RefTitle>
<RefYear>1981</RefYear>
<RefBookTitle>Allgemeine Chirurgie, Entzündungen und Röntgenologie</RefBookTitle>
<RefPage></RefPage>
<RefTotal>Schwenzer N, Grimm G. Allgemeine Chirurgie, Entzündungen und Röntgenologie. 1. Aufl., rev. Nachdr. [S.l.]: [s.n.]; 1981. (Zahn-Mund-Kiefer-Heilkunde; 1).</RefTotal>
</Reference>
<Reference refNo="34">
<RefAuthor>Barnes L</RefAuthor>
<RefAuthor>Eveson JW</RefAuthor>
<RefAuthor>Reichart P</RefAuthor>
<RefAuthor>Sidransky D</RefAuthor>
<RefTitle></RefTitle>
<RefYear>2005</RefYear>
<RefBookTitle>World Health Organization Classification of Tumours. Pathology and genetics of head and neck tumours</RefBookTitle>
<RefPage></RefPage>
<RefTotal>Barnes L, Eveson JW, Reichart P, Sidransky D, editors. World Health Organization Classification of Tumours. Pathology and genetics of head and neck tumours. Lyon: IARCPress; 2005. (World Health Organization classification of tumours; 9).</RefTotal>
</Reference>
<Reference refNo="35">
<RefAuthor>Lewis AG</RefAuthor>
<RefAuthor>Tong T</RefAuthor>
<RefAuthor>Maghami E</RefAuthor>
<RefTitle>Diagnosis and Management of Malignant Salivary Gland Tumors of the Parotid Gland</RefTitle>
<RefYear>2016</RefYear>
<RefJournal>Otolaryngol Clin North Am</RefJournal>
<RefPage>343-80</RefPage>
<RefTotal>Lewis AG, Tong T, Maghami E. Diagnosis and Management of Malignant Salivary Gland Tumors of the Parotid Gland. Otolaryngol Clin North Am. 2016 Apr;49(2):343-80. DOI: 10.1016/j.otc.2015.11.001</RefTotal>
<RefLink>http://dx.doi.org/10.1016/j.otc.2015.11.001</RefLink>
</Reference>
<Reference refNo="36">
<RefAuthor>Schwenzer N</RefAuthor>
<RefAuthor>Ehrenfeld M</RefAuthor>
<RefAuthor>Bacher M</RefAuthor>
<RefTitle></RefTitle>
<RefYear>2010</RefYear>
<RefBookTitle>Mund-Kiefer-Gesichtschirurgie</RefBookTitle>
<RefPage>156-7</RefPage>
<RefTotal>Schwenzer N, Ehrenfeld M, Bacher M. Mund-Kiefer-Gesichtschirurgie. 4., vollst. überarb. u. erw. Aufl. Stuttgart, New York: Thieme; 2010. (Zahn-Mund-Kiefer-Heilkunde). S. 156-7.</RefTotal>
</Reference>
</References>
<Media>
<Tables>
<Table format="png">
<MediaNo>1</MediaNo>
<MediaID>1</MediaID>
<Caption><Pgraph><Mark1>Table 1: Gender distribution of different countries in detail</Mark1></Pgraph></Caption>
</Table>
<Table format="png">
<MediaNo>2</MediaNo>
<MediaID>2</MediaID>
<Caption><Pgraph><Mark1>Table 2: The types of malignant salivary gland tumors – country-specific distribution</Mark1></Pgraph></Caption>
</Table>
<Table format="png">
<MediaNo>3</MediaNo>
<MediaID>3</MediaID>
<Caption><Pgraph><Mark1>Table 3: The different occurrences of minor and major salivary gland tumors worldwide</Mark1></Pgraph></Caption>
</Table>
<Table format="png">
<MediaNo>4</MediaNo>
<MediaID>4</MediaID>
<Caption><Pgraph><Mark1>Table 4: WHO detailed classification of salivary gland tumors (according to Schwenzer/Grimm and Barnes)</Mark1></Pgraph></Caption>
</Table>
<NoOfTables>4</NoOfTables>
</Tables>
<Figures>
<Figure format="png" height="756" width="753">
<MediaNo>1</MediaNo>
<MediaID>1</MediaID>
<Caption><Pgraph><Mark1>Figure 1: Flowchart of the study selection process</Mark1></Pgraph></Caption>
</Figure>
<NoOfPictures>1</NoOfPictures>
</Figures>
<InlineFigures>
<NoOfPictures>0</NoOfPictures>
</InlineFigures>
<Attachments>
<NoOfAttachments>0</NoOfAttachments>
</Attachments>
</Media>
</OrigData>
</GmsArticle>]]></plaintext></textgroup></pgraph></textblock></origdata></gmsarticle>