Oral adenosquamous carcinoma (ASC) is a rare and aggressive type of squamous cell carcinoma (SCC). It is characterized by a squamous component originating at the mucosa and a deep glandular component. ASC may be misdiagnosed as SCC by superficial incisional biopsy including only the squamous component. ASC has a worse prognosis than general variants of SCC, so accurate diagnosis is essential for patient survival. We present a case report of a large ASC arising in the buccal mucosa, first mistaken as general SCC.

Oral examination in a patient with a history of acute lymphoblastic leukemia (ALL) and allogeneic hematopoietic cell transplantation (HCT) needs considerations of leukemia relapse and graft-versus-host disease (GVHD). Oral manifestations may contribute to early detection of relapse or systemic complications making accurate oral examination and diagnosis significant. We report a case of a large tumor like mass arising in a patient with a history of ALL and HCT. The patient had been diagnosed with ALL relapse and was being treated with chemotherapy, and furthermore was suspected of GVHD development.