Intraoral Minor Salivary Gland Research Articles

Pancreatic Differentiation of Oral Minor Salivary Gland Stem Cells.

Stem cells from various sources including major salivary glands have been used to establish pancreatic differentiation in an attempt to provide new treatment options for patients with diabetes mellitus. In contrast, the potential of using the more easily accessible intraoral minor salivary glands has not been evaluated so far. Salivary stem cells were isolated from normal labial minor salivary glands that were removed during the excision of a mucocele and were attempted to differentiate into pancreatic cell lines using a culture medium enriched with activin A, retinoic acid and GLP-1.Real time RT-PCR was used to evaluate the expression of the genes of pancreatic transcription factors MafA, Ptf1a, Hb9 and Arx. Complementary, 22 labial minor salivary gland paraffin-embedded specimens were examined using immunohistochemistry for the presence of the relevant gene products of the pancreatic transcription factors Arx, MafA, Ptf1a and Pdx1. The differentiated salivary stem cells(cells of passage 3) expressed the genes of the pancreatic transcription factors MafA, Ptf1a, Hb9 and Arx even on the first day of the experiment while immunohistochemistry also confirmed the presence of the protein products of Arx, MafA, Ptf1a as well as Pdx1[> 50% of the specimens for Arx(5/8) and MafA(7/8), < 50% for Ptf1a(5/11) and Pdx1(5/11)] in ducts, mesenchymal connective tissue and acinar cells. Labial minor salivary glands may share gene and protein characteristics with pancreas suggesting a possible usefulness for pancreatic regeneration or substitution in cases of deficiency.

Minor Salivary Gland Tumors a Clinicopathological Study and Management

Salivary gland tumors are uncommon and most reported series include tumors affecting both major and minor glands. Very few series have focused solely on intra-oral minor salivary gland tumors. Is to report the clinicopathological d ata of intra-oral minor salivary gland tumors in sample of patients in Baghdad, Most important characteristic features of benign and malignant tumors, different pathological behavior and the importance of pathological classification in changing the management plans. Thirty five patients with tumors of minor salivary gland were analyzed clinlcopathologically and the management of these tumors is discussed. 19 female and 16 male patients, age range from9-79years. The range of duration of tu mors was about 3 years and the size range from 1-7cm. The most commo n site was the palate followed by floor of mouth, lips, cheek, and the maxillary alveolar ridge respectively. Different methods of surgical management of minor salivary gland tumors from simple excision of tumors mass to total maxillectomy were also described.

Intraoral Minor Salivary Gland Tumors: A Retrospective, Clinicopathologic, Single-Center Study of 432 Cases in Japan and a Comparison with Epidemiological Data.

Intraoral minor salivary gland tumors are relatively rare lesions with histological subtypes not commonly found in major salivary glands. This study aimed to retrospectively evaluate the clinicopathologic features of intraoral minor salivary gland tumors from the Tokyo Dental College Hospital, Japan, and compare them with findings from other epidemiological studies. We conducted a retrospective clinicopathologic evaluation of 432 cases of intraoral minor salivary gland tumors [161 male (37.3%) and 271 female (62.7%) patients; mean age: 52.5 and 48.6years for males and females, respectively; age at diagnosis: 7-87 (mean: 50.1) years] from the Tokyo Dental College Hospital between 1975 and 2022, including 283 benign tumors (65.5%) and 149 malignant tumors (34.5%). The most common benign tumor was pleomorphic adenoma (n = 239), whereas mucoepidermoid carcinoma was the most common malignant tumor (n = 74). The mean age of patients with benign and malignant tumors was 48.4 and 53.2years, respectively, with patients with malignant tumors being significantly older (P = 0.0042). The mean age of patients with malignant tumors was significantly higher in males (56.7years) than in females (50.9years) (P = 0.0376), although the mean age of patients with benign tumors did not differ by sex. Tumors were commonly located in the palate [250 cases (57.9%)]. Benign tumors were more frequent in the palate, upper lip, and buccal mucosa, whereas malignant tumors were more frequent in the palate, floor of the mouth, buccal mucosa, and retromolar area. Understanding the features of intraoral minor salivary gland tumors is useful for diagnosis. Our study provides important epidemiological data (patient differences in age at occurrence, sex, and site of origin) that will inform clinicians and researchers.

Salivary gland polymorphous adenocarcinoma: Clinicopathological features and gene alterations in 36 Japanese patients.

Polymorphous adenocarcinoma is a common intraoral minor salivary gland carcinoma in Western countries but is extremely rare in Japan. The current study aimed to characterize the clinicopathological features and status of molecular alterations of polymorphous adenocarcinoma-associated genes, such as PRKD1/2/3, ARID1A, and DDX3X, in a large cohort of Japanese patients with polymorphous adenocarcinoma. We examined the cases of 36 Japanese patients with salivary gland polymorphous adenocarcinoma and 26 cases involving histopathological mimics. To detect gene splits, fluorescence in situ hybridization was carried out for polymorphous adenocarcinoma-associated genes. Additionally, we applied a SNaPshot multiplex assay to identify PRKD1 hotspot mutations. This study revealed the indolent clinical course of polymorphous adenocarcinoma with a high 10-year overall survival rate (92.9%), accompanied by occasional local recurrences and cervical lymph node metastasis (23.3%). Twenty cases (55.6%) of polymorphous adenocarcinoma (but none of the mimics) exhibited alterations in at least one polymorphous adenocarcinoma-associated gene. Rearrangement of polymorphous adenocarcinoma-associated genes and PRKD1 E710D were identified in 17 (47.2%) and 4 (11.1%) cases, respectively; one case showed coexisting PRKD3 split and PRKD1 E710D. In the multivariate analysis, high clinical stage (p= 0.0005), the presence of prominent nucleoli (p= 0.0003), and ARID1A split positivity (p= 0.004) were independent risk factors for disease-free survival. Japanese patients with polymorphous adenocarcinoma showed clinicopathological features similar to those reported in Western countries. This study disclosed that polymorphous adenocarcinoma-associated genetic alterations were common and specific findings in polymorphous adenocarcinomas. The diagnostic role and possible prognostic significance of polymorphous adenocarcinoma-associated genetic alterations in polymorphous adenocarcinomas were suggested.

Laryngeal Papillary Cystadenoma: A Case Report

Papillary cystadenoma is a rare, benign salivary gland neoplasm containing cystic cavities with intraluminal papillary projections. In the head and neck area, it occurs mainly in major and intraoral minor salivary glands, but rarely in the larynx. We report a case of a 67-year-old female with a chief complaint of hoarse voice diagnosed as laryngeal papillary cystadenoma. This paper emphasizes the need to consider papillary cystadenoma as one of differential diagnosis when benign looking lesions are observed in the larynx, where it uncommonly occurs.

The immunophenotype of epithelial to mesenchymal transition inducing transcription factors in salivary gland adenoid cystic carcinomas.

Adenoid cystic carcinoma (ACC) is the second most common malignant salivary glands neoplasms with a controversial biological behavior. Even though these tumors grow slowly, they have increased potential for recurrence and distant metastasis. In order to elucidate this behavior, our study aimed to investigate the immunoexpression in such tumors of the most important transcriptional factors [Twist, Snail, Slug, and zinc finger E-box binding homeobox 1 (ZEB1)] involved in the epithelial–mesenchymal transition process. The highest level of expression was recorded for Twist, present in all the investigated cases, followed by the Slug and Snail, while no tumor parenchyma reactivity was noticed for the ZEB1 factor. There were tumor reactivity differences regarding topography, histopathological variant, and nerve and lymph node invasion status. Thus, tumors developed from the intraoral minor salivary glands, with solid pattern, perineural invasion, locally aggressive and with lymph node metastasis were the most reactive. Therefore, these transcription factors could be useful as prognostic biomarkers and efficient therapeutic targets in such salivary malignancies.

Analysis of the clinicopathological characteristics and prognosis of adenoid cystic carcinoma of the intraoral minor salivary glands: a retrospective study of 40 cases

The clinicopathological aspects and prognostic factors of 40 patients with adenoid cystic carcinoma (ACC) of the intraoral minor salivary glands, treated between 2007 and 2017 at a single institution, were evaluated retrospectively. Twenty-six were female and 14 were male, and they ranged in age from 26 to 81 years (median 55 years). ACC occurred mainly in the palate, with 54.8% of cases presenting T3–T4 lesions. Curative surgery was performed in all patients, and 62.5% of patients were treated with postoperative adjuvant radiotherapy. In the final analysis, positive surgical margins were noted in 57.5% of cases and perineural invasion in 70%. Follow-up was at least 13 months (range 13–141 months, median 59 months). Nineteen patients (47.5%) developed recurrent disease after initial surgery and nine patients had died at the end of follow-up. The 5- and 10-year overall survival rates were 88.3% and 25.6%, respectively. The 5- and 10-year disease-free survival rates were 75.6% and 34.0%, respectively. Patients with a tumour size >4cm and those with positive surgical margins showed a significantly higher risk of local recurrence. Elective neck dissection is suggested for patients with clinically positive lymph nodes or a locally advanced tumour, especially those undergoing microvascular reconstruction. The survival analysis results are similar to those reported previously in the literature.

Prevalence of mucoepidermoid carcinoma among intraoral minor salivary gland tumors: A systematic review and meta-analysis.

This study aimed to synthetize and critically appraise available evidence regarding mucoepidermoid carcinoma (MEC) prevalence among intraoral minor salivary gland tumors (MiSGT). Five main electronic databases and three grey literature databases were searched. The risk of bias (RoB) was assessed using the Joanna Briggs Institute Critical Appraisal Checklist for Studies Reporting Prevalence Data. Proportion meta-analyses were performed. From 1321 studies identified, 82 were included in qualitative synthesis and 80 in meta-analyses. Sixteen were classified as high, 33 as moderate, and 33 as low RoB. A total of 12774 MiSGT were found, of which overall MEC prevalence was 16.5% (95% Confidence Interval [95% CI]=14.8%-18.4%). Most MiSGT were found in the palate (n=7115), although MEC pooled prevalence in this anatomic location was only 13.6% (95% CI=11.7%-15.6%). The retromolar area presented the highest pooled prevalence (58.9%; 95% CI=47.0%-70.3%), followed by gingiva (28.8%; 95% CI=22.7%-35.4%) and tongue (27.2%; 95% CI=21.2%-33.6%). Regarding geographic location, Middle East presented the highest pooled prevalence (20.8%; 95% CI=14.8%-27.6%), followed by America (20.0%, 95% CI=17.2%-23%) and Europe (15.6%; 95% CI=9.2%-23.5%). Among MiSGT, the MEC overall prevalence was approximately 16.5%. Although most MiSGT were found in the palate, the retromolar area was proportionally more affected by MEC.

Utility of Fine Needle Aspiration in Diagnosis of Intraoral Minor Salivary Gland Tumors.

Objective:To evaluate the utility of intraoral fine-needle aspiration cytology (FNAC) in diagnosis of minor salivary gland neoplasms (MSGN) with application of Milan system of reporting salivary gland cytopathology; keeping histopathology as gold standard and to detail the cytological findings of MSGNs.Method:Retrospective study between Jan 2008 and June 2017 (appro × 10 years) on the cytology of the minor salivary gland tumor along with the histopathological correlation. The relevant clinical data was collected from the medical record.Result:Sixty-four cases of MSGNs were included in the study. The histodiagnosis of the 41 were available. Twenty-one cases were diagnosed as malignant, while rest 20 cases were reported as benign. The most common tumor diagnosed was pleomorphic adenoma (PA) (50% cases), followed by mucoepidermoid carcinoma (14%) and adenoid cystic carcinoma (12.5%). The most common site of MSGT was found to be hard palate (44%), followed by soft palate (23%), floor of the mouth (12%), lip (11%), buccal mucosa (5%), and tongue (5%) with no gender predilection. Sensitivity of FNAC for detection of malignancy was 81% while specificity 95%. For malignancies, positive predictive value for malignancies was 17/18 (94.4%) and negative predictive value was 19/23 (82.3%). According to Milan system out of 21 cases in category IV B, 4 cases were found malignant (Category VI), while 1/18 case in category VI turned out to be nonneoplastic lesion (Category II).Conclusion:FNAC is imperative in early diagnosis and subsequent management of MSGNs

Mucoepidermoid carcinoma of the oropharynx: a tumor type with a propensity for regional metastasis unrelated to histologic grade

The designation "mucoepidermoid tumor" is a historic one used in reference to a form of mucoepidermoid carcinoma (MEC) that was believed to be benign. This bygone notion was based on the observation that the vast majority of MECs arising from the intraoral minor salivary glands behave in a benign fashion, particularly when they do not exhibit high grade features. There has been a recent move to partition the oral vault into the oral cavity proper and the oropharynx based on awareness that these compartments are distinct, and that similar tumor types arising from these compartments may behave in dramatically different ways (e.g, oral cavity squamous cell carcinoma vs oropharyngeal squamous cell carcinoma). The pathology databases from 3 large academic medical centers were searched for cases of MECs arising in the oropharynx. Relevant clinical and pathological information was collected from the medical records. Twenty-five cases were identified. They were from 18 females (72%) and 7 males (28%), ranging in age from 31 to 88 years (median, 61). Twenty-two (88%) were classified as low (n = 12) or intermediate (n = 10) grade, and 3 (12%) as high grade. Most arose from the base of tongue (n = 24), but one arose from the lateral pharyngeal wall. The median tumor size was 2.0 cm. Nineteen patients underwent neck node dissections. Of these, 13 (68%) had histologically documented lymph node metastases. MECs that lacked high grade features were almost as likely to metastasize as those with high grade features (50% vs 66%, Fisher exact = 1). Of 3 metastases tested, 2 harbored the MAML2 gene fusion. MECs arising from the base of tongue are associated with an alarmingly high rate of nodal metastases. This behavior cannot be predicted by histologic grading or MAML2 status. The propensity to metastasize may to some degree reflect the unique microenvironment of the oropharynx.

Intra-oral minor salivary gland tumors: A pathological study of 131 cases in the Japanese population

ObjectiveIntra-oral minor salivary gland tumors are relatively rare. This study aimed to clarify the frequency and distribution of intra-oral minor salivary gland tumors in Japanese patients. MethodsWe retrospectively analyzed the histopathological records of 131 patients with minor salivary gland tumors that were surgically treated between 1967 and 2017 at a single institution. ResultsOf the 131 minor salivary gland tumors, 61 (47%) were benign and 70 (53%) were malignant. The male:female ratio was 1:1.8 for benign cases and 1:1 for malignant cases. Most of the tumors occurred in the palate, followed by the floor of the mouth. The most frequent minor salivary gland tumor was pleomorphic adenoma among benign tumors and adenoid cystic carcinoma among malignant tumors. The rarest minor salivary gland tumors were Warthin tumors and basal cell adenocarcinoma, accounting for only 0.8% of all cases. ConclusionsThe present study determined the incidence rates of these rare tumors.

Buccal oncocytoma: Report of a case and literature review

IntroductionMore common in major salivary glands, oncocytomas are very rare tumors. They commonly occur in the parotid gland and are painless slow growing predominantly benign tumors. The term “oncocytoma” was introduced by Jaffe to designate those tumors of the salivary glands that consist predominantly of oncocytic cells lining the salivary ducts (1) Similalry, Meza- Chavez had proposed the name “oxyphilic granular cell adenoma. (2) Oncocytomas are extremely rare, benign and slow growing in nature. Here we present a rare case of buccal oncocytoma which is to our knowledge the 19th case of intraoral minor salivary gland tumor and the 7th reported case of buccal oncocytoma.Case presentationHere we present an exceedingly rare case of buccal oncocytoma in a 14 years boy who presented to the department of ENT with right buccal swelling for 6 months. He was posed the diagnosis of buccal cyst after cytological examination supported by CT scan. He then underwent an excisional biopsy where the final diagnosis was made as Buccal Oncocytoma.ConclusionsThough very rare in the picture, conditions like salivary gland oncocytomas still are reported on and off in the literature. The treatment of which is complete surgical excision.

Molecular features of adenoid cystic carcinoma with an emphasis on microRNA expression.

Molecular features of adenoid cystic carcinoma with an emphasis on microRNA expression.

A Case of Mucoepidermoid Carcinoma Arising from the Intraoral Minor Salivary Gland

Salivary gland tumors comprise almost 5% of head and neck malignancies, and minor salivary gland tumor which account for 10-15% of all salivary gland neoplasm are infrequently malignant. The mucoepidermoid carcinoma (MEC) is second most common tumor in minor salivary gland. It usually presents as a painless, rubbery-hard or soft mass, which may be fixed or mobile into the underlying structure. The predilection sites of intraoral MEC are palate, cheek, mandible, lip, and tongue, etc. There are very few published reports of MEC occurred in retromolar trigone. Only one case has been reported so far. Recently, we experienced a-70-year old man with a mass in retromolar trigone, which was finally diagnosed as MEC. We report the unique case with literature review.

Adenoid Cystic Carcinoma of the Buccal Mucosa with Rare Delayed Frontal Bone Metastasis: A Case Report

Adenoid cystic carcinoma (AdCC) is a malignant neoplasm, which accounts for 5-10% of all salivary gland tumors (1). About 50% of these tumors originate from intraoral minor salivary glands usually in the hard palate (1). Three clinically obvious characteristics of AdCC include slow growth rate, perineural invasion and high incidence of distant metastasis (1). The most commonly-affected sites of distant metastasis are bone, liver and brain, followed by lungs (2). Lymph node metastases are rare; The most common sites involved by hematogenous spread are lungs (2). This is a report about a patient with a rare form of AdCC on buccal mucosa with an unusual metastasis to the frontal region after a two-year follow up.

Lymphoepithelial infiltrate of palatal minor salivary glands: implications for diagnostic work-up

Benign lymphoepithelial lesions (BLLs) usually affect the parotid glands, resulting in their asymmetrical enlargement. The condition can be associated with Sjögren's syndrome (SS), which in turn may predispose the affected patient to the development of malignant lymphoma. BLLs arising in the intraoral minor salivary glands are rare; such a lesion should prompt the work-up for SS. In some instances, a BLL of a minor salivary gland could represent the initial stage of a mucosa-associated lymphoid tissue (MALT) lymphoma. A case of BLL arising in the palatal minor salivary glands is reported here. The importance of an appropriate diagnostic work-up is emphasized and the relationship of BLL with SS is reinforced.

Immunohistochemical evaluation of the mTOR pathway in intra-oral minor salivary gland neoplasms.

The aim of this study was to investigate the expression of upstream and downstream molecules of the oncogenic mTOR signaling pathway in intra-oral minor salivary gland tumors (SGTs). Tissue samples consisted of 39 malignant and 13 benign minor SGTs, and 8 controls of normal minor salivary glands (NMSG). An immunohistochemical analysis for phosphorylated Akt, 4EBP1 and S6 (total and phosphorylated), and eIF4E was performed. Expression of pAkt and 4EBP1 was observed in all SGTs and in most NMSG. p4EBP1 was detected in almost all SGT cases, NMSG being negative. S6 immunoreactivity was observed in 37.5% of NMSG, 92.3% of benign and 100% of malignant SGTs, while pS6 expression was observed in 77% of benign and 95% of malignant SGTs, but not in NMSG. Finally, eIF4E was expressed in 12.5% of NMSG, 69.2% of benign, and 76.9% of malignant tumors. All molecules studied had statistically significantly lower expression in NMSG compared with SGTs. Moreover, malignant neoplasms received higher scores compared with benign tumors for all molecules with the exception of eIF4E. The mTOR signaling pathway is activated in SGTs, especially in malignancies. Therefore, the possible therapeutic role of targeting the mTOR pathway by rapamycin analogs in SGTs needs further investigation.

Clear cell carcinoma of hard palate: A rare case report

Clear cell carcinoma is a rare low-grade carcinoma. It occurs almost exclusively in the intraoral minor salivary glands and represents less than 1% of all salivary gland tumors. It is a new addition in the recent World Health Organization (WHO) classification of salivary gland tumors. The condition follows an indolent course and treatment includes wide surgical excision with or without adjuvant radiotherapy. This case report highlights a very rare case of a 40-year-old female patient with characteristic clinical and radiographic features, diagnosis and management including significant histopathologic features. Combining our case with those reported in literature, a total of 70 cases confirm that clear cell carcinoma is a low-grade malignant neoplasm with distinctive clinical and pathologic features, which highlight the rarity of the condition.

Clinicopathological characteristics of tumours of the intraoral minor salivary glands in 170 Brazilian patients

Tumours of the minor salivary glands are relatively uncommon, and publications from around the world normally include tumours of both the minor and major salivary glands, making it difficult to assess their prevalence and distribution. Our aim was to evaluate retrospectively the clinicopathological features of a series of tumours of the intraoral minor salivary glands from two universities in Rio de Janeiro, Brazil, and to compare the data with those from other epidemiological studies. A total of 170 such tumours were diagnosed from 1942 to 2012, and were selected from two university departments of oral pathology. Eighty-nine of the tumours were benign (52%). Pleomorphic adenoma (n=75) and mucoepidermoid carcinoma (n=23) were the most common benign (44%) and malignant tumours (14%), respectively. There were 104 female patients (61%) and both benign and malignant tumours affected more women than men. Significantly more tumours were in the palate (n=95, 56%; p=0.001). We conclude that these tumours had features similar to those from other studies from North and Latin America, but differ from the results presented from Asia. Further studies should be designed to highlight possible geographical and population-specific characteristics of these tumours.

A multi center clinico-pathologic study of intraoral minor salivary gland tumours in malaysia

A multi center clinico-pathologic study of intraoral minor salivary gland tumours in malaysia