Background: Salivary gland tumors are rare and with different malignant potential. Immunohistochemistry is useful, especially Ki67, a marker of cell proliferation, for its prognostic information. On the other side, the mucin MUC-1 is overexpressed and loses its exclusively apical membranous localization and is aberrantly glycosylated in mucoepidermoid carcinoma of salivary glands. In the present work, we investigated the quantitative expression of tumor proliferative index and localization and overexpression of MUC-1 in the mucoepidermoid carcinoma of the human salivary glands, not studied is these organs, to determine their relationship with the histological grade and prognosis. Methods: H/E staining and immunohistochemistry with MUC-1 and Ki67 antibodies was performed on 10 cases. Results: The markings of the mucoepidermoid carcinoma depended on the histological grade; in low- grade tumors with MUC-1 only 10 to 25% of the cells were labeled, in contrast to high- grade tumors, with 75 to 90% labeled cells. They also differed in cell proliferation; in the low-grade tumors was 15% and in high-grade tumors it was greater than 30%. Conclusion: MUC-1 overexpression is significantly higher in high-grade mucoepidermoid carcinoma, as is Ki67 marking, results that are associated with tumor prognosis.

Objective:Acinic cell carcinoma (CCA) is the third malignant epithelial tumor of the salivary glands in adults; low-grade tumor of malignancy, composed of neoplastic cells with serous acinar differentiation. The objective of this work was to analyze 12 cases of CCA according to their location, clinical characteristics, histological and immunohistochemical pattern and cell types, following the latest classification of the World Health Organization. Methods: The study included 12 cases of CCA from the files of salivary tumor biopsies of our work team, corresponding to the period 1997-2020. A numerical code was used to identify the samples, preserving the identity of the patients. Histological sections of the paraffin-embedded biopsies were evaluated with H/E, PAS and Toluidine blue and immunostained with the monoclonal antibodies pancytokeratin AE1 / AE3, Ki67, MUC-1 and mammaglobin. Results: The most frequent histologic pattern was the solid type as a single pattern or integrated with other patterns of lesser development, with almost exclusive location in the parotid gland and more frequent in women. Cells like normal acinar serocytes predominated in the solid growth pattern. The most frequent cell type in the microcystic patternwas the nonspecific glandular cell together with a lower proportion of acinar and intercalated duct-like cells. The papillary-cystic pattern was lined by nonspecific glandular cells. No clear cells found. With Ki67 a low cell proliferation was demonstrated in all the cases studied. Cell labeling for MUC-1 was grade 1 positive (less than 10% immunoreactive cells) and negative for mammaglobin.Conclusions: Patient follow-up is a priority because CCA tends to recur and metastasize and its behavior can become aggressive. We must deepen the study of its proliferative capacity as a treatment and prognosis tool, especially with immunohistochemistry and standardized molecular biology methods.