Clinicopathological Features of 26 Intraoral Polymorphous Adenocarcinomas from a Single Brazilian Institution.

PURPOSE: This study describes a large, well-documented case series of salivary gland polymorphous adenocarcinomas (PAC) from a single Brazilian center. METHODS: Demographic data, clinical presentation, histopathological and immunohistochemical features from 26 cases of PAC were analyzed and discussed in detail. RESULTS: Most patients were females (n = 21), with a ratio of 1:4.2 (male: female) with a mean age of 58.8 years (ranging from 36 to 84 years). The most common clinical presentation was a fibrocollagenous, firm nodular lesion, with a mean size of 2.46 cm (ranging from 0.5 to 3 cm). Most lesions occurred on the palate (n = 16), followed by buccal mucosa (n = 3), upper lip (n = 3), buccal vestibule (n = 2) and alveolar ridge (n = 1). Histologically, various growth patterns were observed, including tubular, solid, cribriform, papillary, and cystic. Additionally, glomeruloid slit-like structures, mucous, and clear cells were noted. Surface papillary epithelial hyperplasia was observed in a few cases. Nine cases exhibited myxoid and collagenous areas, while two cases showed fusiform areas and another case demonstrated squamous differentiation. Clear cell predominance was noted in two cases, and peri- and intraneural invasion was seen in eight cases. Immunohistochemical analysis revealed positivity for S-100, p63 and CK7, and negativity for p40 in all cases. The Ki-67 proliferation index was markedly low in most cases, with a mean of 2.5%. CONCLUSION: We have provided a broad, detailed description of the clinical and microscopic features of PAC in a large, Brazilian cohort. These findings, in a resource-limited area, may be quite useful for establishing a proper diagnosis.

Clinical and demographic features of minor salivary gland tumors: A collaborative study of 480 cases.

OBJECTIVE: To describe the frequency, clinical, and demographic features of minor salivary gland tumors and possible associated factors. MATERIALS AND METHODS: A cross-sectional study was conducted. Clinical and demographic data were collected from biopsy records of two oral pathology services. Chi-square test, Fisher's exact test, and descriptive statistical analysis were performed. RESULTS: A total of 480 (0.89%) minor salivary gland tumors were retrieved, 272 (56.7%) benign and 147 (30.7%) malignant. Sixty-one (12.6%) had no subtype specification. Most patients were women (307/64.0%), in sixth decade of life (80/16.7%), with a mean age of 45.32 years. Palate was the most common site (336/70.1%). Pleomorphic adenoma (PA; 245/51.1%), mucoepidermoid carcinoma (MEC; 70/14.6%), and adenoid cystic carcinoma (ACC; 43/8.9%) were the most frequent tumors. Symptomatic case, recurrence, and tobacco use were associated with malignancy (p < 0.05). PA and MEC were more frequent in palate (p < 0.05). No association between the three most frequent histological types and gender or age group was observed (p > 0.05). CONCLUSIONS: This represents one of the largest exclusive series of minor salivary gland tumors in Brazil and worldwide. PA, MEC, and ACC were the most frequent tumors. Clinical and demographic data are similar from Brazilian studies or from other countries.