INTRADUCTAL CARCINOMA OF THE SUBMANDIBULAR GLAND

Intraductal carcinoma, a low-grade malignancy of the salivary glands, is an exceeding rare malignant tumor. With about 40 cases reported, it is more common in the parotid gland. We report 1 case of intraductal carcinoma arising in the submandibular gland of a 24-year-old female patient. Microscopically, the tumor presented with a macrocystic architecture lined by intraductal malignant cell proliferation resembling atypical ductal hyperplasia or in situ ductal carcinoma of the breast. In some areas, the tumor showed typical features of conventional salivary duct carcinoma with high-grade solid nests, comedonecrosis, and apocrine differentiation, without evidence of invasion. The tumor cells were positive for AE1/AE3 antibody, cytokeratin (CK) 7, and epithelial membrane antigen (EMA). Basal and myoepithelial cells were evident surrounding the ductal structures, and were positive for α-smooth muscle actin (α-SMA), calponin, and p63. Focal positivity for S-100 and mammaglobin was also observed. The patient underwent surgical treatment and has no evidence of the disease after 41 months of follow-up examination.