AN UNUSUAL TYPE OF SOLID CARCINOMA OF SALIVARY GLANDS: A CLINICOPATHOLOGIC AND IMMUNOHISTOCHEMICAL STUDY

An unusual histologic type and low-grade malignancy of salivary gland (SG) carcinomas, namely solid carcinoma (SC), is reported. Histopathologic characteristics of 12 cases of the SC include (1) large solid nest structure, (2) isomorphic and blandness of the epithelial cells in cytoloogy, (3) squamous metaplasia and keratinization in different degrees. (4) infiltrative growth pattern. Immunohistochemical stainings reveal that the cells of the SCs are reacted positive with anti-cytokeratins 12 and 27, anti-S-100P, anti-EMA antibodies in different degrees, and negative with anti-desmin, anti-GFAP, anti-lysozyme antibodies. The positive reactions with anti-CEA, anti-actin, and anti-myoglobin are detected in a few individuals. Follow-up data show the recurrence rate and mortality of the SC are 73% and 18% respectively. The histogenesis of SC and differential diagnosis are also discussed in the paper.