Submandibular gland cystadenocarcinoma with mucinous adenocarcinoma-like areas: a case report

Cystadenocarcinoma is primarily characterized by cystic structures of varying sizes, that are lined by epithelial cells. As a rare neoplasm, only four cases of cystadenocarcinoma of submandibular glands have been previously reported. Herein, we reported a unique case of submandibular gland cystadenocarcinoma in a 44-year-old man. By in large, this case had typical morphologic cystadenocarcinoma features. However, mucinous adenocarcinoma-like areas were additionally observed in the tumor tissues. This case was initially misdiagnosed as mucinous adenocarcinoma due to the low incidence of submandibular gland cystadenocarcinoma and the presentation of mucinous adenocarcinoma-like areas in the tumor tissues. Histopathology of additional tumor tissues revealed that mucinous adenocarcinoma-like areas accounted for only a small percentage of the tumor tissues, confirming the submandibular gland cystadenocarcinoma diagnosis.