A clinico-pathologic study of 311 intra-oral salivary gland tumors in Thais

Background:  There have been several epidemiologic studies on intra-oral salivary gland tumors in several countries, but little is known of these tumors in Thailand.
Objectives:  To determine the relative frequency and distribution of various types of intra-oral salivary gland tumors in the Thai population.
Methods:  The files of the Department of Oral Pathology, Faculty of Dentistry, Chulalongkorn University, from 1969 to 2007 were searched for intra-oral salivary gland tumors. Histopathologic slides were reviewed and reclassified according to the 2005 WHO Classification of Head and Neck Tumors. The age, gender, race, and anatomical distribution of the tumors were collected from the patients' records.
Results:  Of the 16,358 accessioned cases, 311 cases (1.90%) were diagnosed as intra-oral salivary gland tumors. One hundred and forty-seven cases (47.27%) were benign tumors, while 164 cases (52.73%) were malignant tumors. The mean age of the patient ± SD = 41.57 ± 16.65 years. Females outnumbered male patients by a ratio of M:F = 1:1.38. Almost all except one patient were Thais. Pleomorphic adenoma was the most common intra-oral salivary gland tumor. The majority of cases occurred at the palate.
Conclusions:  Pleomorphic adenoma is the most common intra-oral salivary gland tumor and the most common benign intra-oral salivary gland tumor, while mucoepidermoid carcinoma is the most common malignant intra-oral salivary gland tumor. Intra-oral salivary gland tumors in Thailand elicit similar trend as in previous studies, with only minor differences such as the ranking of some tumors, the higher incidence of intra-bony location, and the lower incidence of polymorphous low-grade adenocarcinoma.     

A clinicopathologic study of 196 intraoral minor salivary gland tumours

We present a retrospective study of 196 patients with intraoral minor salivary gland tumours, 128 malignant and 68 benign, diagnosed from 1954 to 1993 in the A.C. Camargo Hospital, São Paulo, Brazil. Sixty-five percent of the cases occurred in the palate, followed by tongue (9.7%) and retromolar area (6.1%). Pleomorphic adenoma was the most common benign tumour, and mucoepidermoid carcinoma was predominant among the malignant tumours. Surgery was the main treatment method and postoperative radiotherapy and radiotherapy alone were used in 40 and 15 patients, respectively. Local recurrence was observed in two patients with pleomorphic adenoma and in eight patients with malignant tumours. Regional lymph node metastases occurred in four cases and distant metastases in five. Forty-six of 47 patients with benigh tumours who were followed up from 1 to 7 years were alive without disease. Twenty-four of 79 patients with malignant tumours who were followed up for at least 5 years died due to the tumour and 47 were alive without disease.     

Crystalloid architecture of a sialolith in a minor salivary gland

A sialolith from a minor salivary gland of the mucosa of the upper lip was studied morphologically and analytically. Under stereoscopic microscopic visualisation, no core or any concentric laminar structure was found in the sialolith and it had a transparent glassy appearance. Scanning electron microscopy revealed differences between the internal structure of the sialolith and its external structure. No microbes were observed but some mineralized inclusion bodies were seen. X-ray diffraction indicated the absence of inorganic crystals in the sialolith, while energy dispersive x-ray microanalysis revealed a high content of S followed by Ca, Si and Na and little and scarce P on the fracture surface, with S, Na, Ca and P being distributed throughout the external coating of the sialolith. The results suggest that the sialolith was young and consisted of a crystalloid body with an incipient coating undergoing calcification.     

Epithelial salivary gland tumors of children and adolescents in west China population: a clinicopathologic study of 79 cases

Objective:  Determine the clinical and histopathologic features of epithelial salivary gland tumors of children and adolescents.
Methods:  A total of 79 cases of epithelial salivary gland tumors of children and adolescents were retrieved from the files. Information about demographic, clinical, histopathologic characteristics, and follow-up status were analyzed.
Results:  Sixty tumors (75.9%) were benign and 19 (24.1%) malignant. The most common tumor overall was pleomorphic adenoma (PA). The parotid was the most frequently involved site (43.0%). PA was the most common type of benign tumor. The most common malignant tumor was mucoepidermoid carcinoma. Five patients with parotid PA and two cases with palate myoepithelioma showed local recurrences. One patient with mucoepidermoid carcinoma showed local recurrences and died from the tumor 3 years after the initial treatment. One patient with adenocarcinoma presented local and neck recurrences, and died 4 years after initial treatment.
Conclusions:  Our data showed that the salivary gland tumors in children and adolescents may be the higher incidence of benign tumors, especially of PA; the slightly higher tendency for female predominance; the higher incidence of parotid glands. Mucoepidermoid carcinoma was the most common malignant tumor, with majority of low grade. Initial treatment should be planned to excise the tumor completely with satisfactory margins. The neck dissections or postoperative radiotherapy were performed in patients with low differentiation malignancies, or patients who present nodal metastasis or with clinically suspicious regional metastasis.     

The accuracy of fine needle aspiration cytology in the clinical diagnosis of minor salivary gland tumours

The objective of this study was to investigate the accuracy of fine needle aspiration cytology (FNAC) and biopsy for the clinical diagnosis of minor salivary gland tumours (MSGTs). This retrospective study of 32 MSGT cases was conducted over a 5-year period. Clinical features including age, sex, and location of the tumour were obtained from the patient clinical records. All cases were also assessed histologically according to the 2017 World Health Organization Classification of Head and Neck Tumours. The results of FNAC and biopsy were correlated with those of histopathology, and their sensitivity, specificity, and diagnostic efficacy were calculated using histopathology as the gold standard. Eighteen malignant MSGTs (56.3%) and 14 benign MSGTs (43.8%) were diagnosed by pathological diagnosis. The most common malignant tumour was mucoepidermoid carcinoma (seven cases, 38.9%). Most benign cases were pleomorphic adenomas (13 cases, 92.9%). FNAC was performed for 23 cases and biopsy for 13 cases. The sensitivity and specificity of FNAC were 66.7% and 91.0%, respectively, while those of biopsy were 90.0% and 100.0%, respectively. Although FNAC is a minimally invasive and cost-effective procedure, it is less accurate than biopsy in the assessment of MSGTs. Repeated FNAC or biopsy should be considered in negative and unsatisfactory FNAC cases.     

Relative frequency of central odontogenic tumors: a study of 1,088 cases from Northern California and comparison to studies from other parts of the world.

PURPOSE: To determine the relative frequency of central odontogenic tumors in relation to all biopsy specimens and to one another in an oral pathology biopsy service and to compare the data with previous studies from different parts of the world. METHODS: Files from the Pacific Oral Pathology Laboratory of the University of the Pacific, San Francisco, CA served as a source of material for this study. Files were systematically searched for all cases of central (intraosseous) odontogenic tumors during a 20-year period. RESULTS: Central odontogenic tumors were identified in 1,088 (1.2%) cases out of the 91,178 accessed. Individually, of all odontogenic tumors, 75.9% were odontomas. The prevalence of the remaining tumors appears to be a rare occurrence. The second most common was ameloblastoma (11.7%), followed by odontogenic myxoma (2.2%). Odontomas are considered hamartomas or developmental anomalies. When excluded from the list of individual odontogenic tumors, ameloblastoma is the most common (48.5%), followed by odontogenic myxoma (9.2%), adenomatoid odontogenic tumor (7.3%), ameloblastic fibro-odontoma (7.3%), ameloblastic fibroma (6.5%), calcifying odontogenic cyst (6.5%), and odontogenic fibroma (6.1%). Each remaining tumor comprises less than 4%. CONCLUSIONS: Studies related to the relative frequency of individual odontogenic tumors from different parts of the world are difficult to compare because most studies are outdated, the list of tumors is limited, and new entities are not included. To determine the real relative frequency, further studies should be conducted, especially in Western societies, by experienced pathologists in the field of odontogenic tumors.     

Rare expression of the c-erbB-2 oncoprotein in salivary gland tumors: an immunohistochemical study

An immunohistochemical study of c-erbB-2 oncoprotein expression was carried out on 201 cases of primary salivary gland tumors, using a polyclonal antibody, raised to the intracytoplasmic domain of the c-erbB-2 oncogene product. An intense membrane reactivity was observed in one case of sialocarcinoma transformed from pleomorphic adenoma (n = 8) and one case of mucoepidermoid carcinoma (n = 22). A comparative histopathologic evaluation of c-erbB-2 positive tumors showed marked variation in cell size, nuclear pleomorphism, multinucleation, a high mitotic rate and increased lymphoid cell infiltration and an aggressive clinical course with poor survival. The results indicate that c-erbB-2 oncoprotein is rarely expressed in malignant salivary gland tumors. However, the overexpression appears to have a distinct histopathologic feature, but a larger study incorporating histopathology and clinical data would be necessary to correlate the significance of c-erbB-2 oncogene product in salivary malignant tumors.     

Sebaceous lymphadenoma of the lip: report of a case of minor salivary gland origin

A case of sebaceous lymphadenoma occurring in the lip of a 73-year-old female is described. The patient had noticed a painless mass in the region of her upper lip for a year. The surgically removed tumor, measuring about 10 mm in diameter, was located just beneath the lip mucosa, expanding into the submucosal and muscle layer. Histologically, the tumor was well encapsulated and consisted of scattered round-shaped islands of small squamous epithelial cells with focal but apparent sebaceous differentiation in a background of lymphoid stroma. This is the first case report of sebaceous lymphadenoma of minor salivary gland origin.     

Relative frequency of peripheral odontogenic tumors: a study of 45 new cases and comparison with studies from the literature

BACKGROUND: Peripheral (extraosseous) odontogenic tumors are rare, and reports in the literature have mainly been single case reports or a small series of cases. The aim of this study was to determine the relative frequency of peripheral (extraosseous) odontogenic tumors relative to one another and relative to their central (intraosseous) counterparts in an oral pathology biopsy service and to compare these data with information available in the literature. METHODS: The files of the Pacific Oral and Maxillofacial Pathology Laboratory of the University of the Pacific, San Francisco, CA, USA, served as the source of material for this study. Files were systematically searched for all cases of peripheral odontogenic tumors (POTs) during a 20-year-period. RESULTS: There were 91,178 cases accessed in which central and POTs were identified in 1,133 (1.24%), central tumors in 1,088 (1.2%), and peripheral tumors in 45 (0.05%). Peripheral tumors accounted for 4% of all 1133 central and POTs. Peripheral odontogenic fibroma (PODF) was the most common of the 45 POTs accounting for 51.1% (23 cases) followed by peripheral ameloblastoma (PA) 28.9% (13 cases) and peripheral calcifying cystic odontogenic tumor (PCCOT) 13.3% (six cases). Peripheral calcifying epithelial odontogenic tumor, peripheral ameloblastic fibroma, and peripheral ameloblastic carcinoma were also identified--each comprised 2.2% (one case each). PODF was more common than its central counterpart by a 1.4:1 ratio. This was the only peripheral tumor that was more common than its central counterpart. PA accounted for 9.3% of all ameloblastomas and PCCOT for 26% of all calcifying cystic odontogenic tumors. CONCLUSION: There is only scarce information in the literature on the relative frequency of POTs. Additional studies should be conducted to determine the true relative frequency. To ensure accuracy, pathologists with experience in the field of odontogenic tumors should conduct these studies. Intraosseous tumors that perforate through the bone to the gingival tissue, clinically presenting as 'peripheral tumors' should be excluded.     

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 12 774 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.     

Evaluation of the nucleolar organizer region associated proteins in minor salivary gland tumors

Forty-three intraoral salivary gland tumors were studied to determine the value of the AgNOR technique in the assessment of these neoplasms. Well defined black dots were visible in the nucleii of all the specimens studied. The mean AgNOR count per nucleus for each tumor was calculated as follows: pleomorphic adenoma (n = 15) 1.52; Polymorphous low-grade adenocarcinoma (n = 12) 1.90; adenoid cystic carcinoma (n = 6) 2.92; mucoepidermoid carcinoma (n = 4) 1.93; carcinoma ex mixed tumor (n = 4) 2.05; undifferentiated carcinoma (n = 1) 3.13 and epithelial-myoepithelial carcinoma (n = 1) 2.23. The difference between the means of benign and malignant tumors (P less than 0.01) and polymorphous low-grade adenocarcinoma and adenoid cystic carcinoma (P less than 0.01) were highly significant. The overlapping of the AgNOR count between various tumors prohibited the use of this technique as an absolute criterion in establishing a final diagnosis. It could however be used as a diagnostic aid in differentiating between salivary gland neoplasms.     

Island of salivary gland in adipose tissue: a report of three cases

Although uncommon, many variants of lipomatous lesions in or around salivary glands have been reported in the literature. We report a series of three such cases in the minor salivary gland region. The first case (oral floor) is a well-circumscribed lipocytic lesion admixed with glandular components (mucous acini, serous demilunes and ducts). The second case (alveolar mucosa) is a diffuse lipomatous proliferation with entrapped salivary glandular elements, muscles and blood vessels. The third case (palate) is similar to the first case but the gland is located at the periphery of the lesion. The purpose of the article was to report these three lesions and discuss in relation to other pertaining lipomatous lesions (sialolipoma, lipoadenoma, lipomatosis, lipometaplasia in pleomorphic adenoma and infiltrating lipoma).     

A study of the extracellular matrix in salivary gland tumors

BACKGROUND: Epithelial-mesenchymal interactions constitute fundamental phenomena in the development and maintenance of the characteristic branching pattern seen in salivary glands. This study was undertaken to discuss the extracellular matrix (ECM) role in morphogenesis and cellular differentiation of salivary gland tumors originating from the intercalated duct. METHODS: The ECM components, laminin (LN), type IV collagen, fibronectin (FN), and tenascin (TN) were revealed using a streptoavidin-biotin immunohistochemical technique and analyzed in 34 cases of salivary gland tumors: pleomorphic adenoma (PA); myoepithelioma; basal cell adenoma (BCA); polymorphous low grade adenocarcinoma (PLGA); and adenoid cystic carcinoma (ACC). RESULTS: LN and type IV collagen were present in all tumors, confining well-organized duct-like structures, separating them from the stroma, or surrounding cell clusters. In PA and myoepithelioma, the basement membrane (BM) fragmentation was observed through LN and type IV collagen staining around each individual spindle-shaped cell, which was strictly related to the cell modification. Interestingly, BM interruption could not be seen in the malign tumors, however, was frequently augmented in some cases. LN, type IV collagen, and FN were also found in the stroma of all tumors studied, except for the pseudocystic spaces of ACC, which were only delimited by replicated LN and type IV collagen. TN exhibited a variable expression, being more intense in solid ACC. CONCLUSIONS: LN and type IV collagen were always present around morphologically well-differentiated duct-like structures in all tumors studied. BM interruption could not be seen in the malign tumors, on the contrary BM production was evident, which is probably related to invasion. FN was present in the stroma of all tumors, but TN was mostly observed in less differentiated and higher degree of malignancy tumors, such as solid ACC.     

�����ٶ�������34���ٴ�����

目的    探讨舌下腺恶性肿瘤的发病情况、病理特征、治疗方式及疗效特点。方法    对1979—2010年中国医科大学附属口腔医院及中国医科大学附属第一医院收治的34例经病理确诊的舌下腺恶性肿瘤病例临床资料进行回顾性分析。结果    34例舌下腺恶性肿瘤患者中,男15例,女19例;年龄20～86岁,平均52.12岁;40～60岁年龄段为22例（64.71%）;病理类型中腺样囊性癌居首位（70.59%）;治疗方式主要是局部扩大切除+颈淋巴结清扫术;3、5、10年存活率分别为82.35%、76.47%、47.06%。结论    舌下腺恶性肿瘤女性患者发病率略高于男性;腺样囊性癌和黏液表皮样癌是舌下腺常见的恶性肿瘤;首次正确选择术式,且术后辅助放化疗是降低复发和转移的主要因素。     

The role of bronchoscopy and gastroscopy in intraoral minor salivary gland carcinomas at initial staging

Intraoral minor salivary gland carcinomas are rare tumours the incidence, distribution, and prognostic factors of which differ. The prognosis of patients depends on the presence of metastases or synchronous malignant diseases that usually affect the lungs. The incidence of metastases has been reported to be about 9% at the time of primary staging. The aim of this study was to assess the value of bronchoscopy and gastroscopy in the routine staging of minor salivary gland cancers.     

Intraoral minor salivary gland tumors: a retrospective study of 62 cases in a Venezuelan population

From 1968 to 1992 sixty-two cases of tumors of minor salivary glands were diagnosed from a Venezuelan population at the Oral Histopathology Laboratory of the Central University of Venezuela School of Dentistry. The diagnosis of individual tumors was based on the 1991 World Health Organization classification. Tumors were analyzed considering histological type, age and sex of the patient, and intraoral location. Pleomorphic adenomas constituted the most common histological diagnosis of the benign sample (71%). and 62% of the malignant tumors were diagnosed as mucoepidermoid carcinomas. The principal location was the palate, and a marked female prevalence was observed. Geographic differences appear to exist when compared with results of studies representing a cross-section of different world population groups.     

Coexpression of intermediate-sized filaments in sialadenoma papilliferum and other salivary gland neoplasms

The neoplastic cells present in a sialadenoma pappiliferum were found by immunoperoxidase method and immunofluorescent staining technique to co-express 3 different types of intermediate-sized filaments (IFs) defined by monoclonal antibodies to cytokeratin, vimentin and desmin. When other salivary gland tumors such as 18 pleomorphic adenomas, 15 adenolymphomas, 2 oxyphilic adenomas, 7 mucoepidermoid tumors, 5 acinic cell tumors, 8 adenoid cystic carcinomas and 6 adenocarcinomas were examined immunohistochemically for the expression of IFs, no tumors with all 3 types of IFs observed in sialadenoma papilliferum were found.