Primary intestinal-type adenocarcinoma: Report of a rare case involving a young patient.

The aim of this report was to describe a rare example of sporadic intestinal-type adenocarcinoma of the major salivary glands and oral cavity. A 23-year-old female patient presented an asymptomatic, progressive-growing mass involving the floor of mouth and the left submandibular gland. Fine-needle aspiration cytology, imaging exams, and surgical specimen findings were consisted with the diagnosis of primary intestinal-type adenocarcinoma, despite its similar immunohistochemical results with colorectal adenocarcinoma. Adjuvant chemotherapy and radiotherapy were performed, but the patient developed multiple metastatic lesions after one year of initial the intervention and deceased following 13 months of follow-up, despite several therapeutic efforts. We verified that sporadic cases of primary intestinal-type adenocarcinoma still lack information regarding etiology and tumorigenesis, especially in young and females. A complete diagnostic workflow is indispensable to rule out the presence of primary colorectal adenocarcinoma.