A case of mantle cell lymphoma (MCL) detected with initial symptoms in the oral region

We encountered a case of mantle cell lymphoma (MCL) located in the oral cavity, diagnosed through the analysis of a biopsy sample from a palatal mass. The patient was an 85-year-old female who was referred to our department due to a palatal mass. Contrast-enhanced computed tomography (CT) showed a shadow of a mass in the palate and several enlarged lymph nodes on both sides of the neck. Magnetic resonance imaging revealed diffuse enlargement of the palatal soft tissue, with a faint and uniform signal on T2-weighted imaging. The signal was markedly hyperintense on diffusion-weighted imaging, with multiple lymph node enlargements in the bilateral parotid glands, neck, submental area, and clavicular fossa. Histopathological findings showed dense infiltration of small lymphocyte-like tumor cells beneath the epithelium. Immunostaining was positive for CD20, CD5, and cyclinD1, confirming the diagnosis of MCL. Fluorescence in situ hybridization using a bone marrow aspirate showed positive BCL translocation and negative p53 deletion. Positron emission tomography-CT indicated higher fluorine-18-deoxyglucose accumulation in the palate, as well as in the bilateral cervical, axillary, mesenteric, iliac, and enlarged inguinal lymph nodes, compared to the liver. The Lugano classification was advanced Stage IV, and the patient underwent six courses of combination therapy of bendamustine and rituximab, resulting in complete remission.