Mantle cell lymphoma presenting as a symmetrically hard palatal swelling: A case report and review of the literature

Mantle cell lymphoma (MCL) is a rare B-cell neoplasm accounting for approximately 3-10% of all non-Hodgkin lymphomas (NHLs). Initial clinical manifestation in the oral cavity is extremely rare. We report a case of MCL involving the hard palate. The patient, a 92-year-old man, presented at the department of oral surgery of our hospital because of swelling of the palate, causing instability of his maxillary denture. On examination, the hard palate was symmetrically swollen, and computed tomography revealed an extensive soft tissue mass with osteolysis. Biopsy of the mass disclosed monotonous diffuse infiltrates of small to intermediate-sized lymphoid cells underneath the squamous epithelium. Immunohistochemistry revealed that the cells were positive for CD5, CD20, CD79a, bcl-2, cyclin D1, ki-67 (MIB-1 index, 68.5%) and (weakly or strongly) CD43, and negative for CD3, CD10, CD21, CD23, bcl-6, TdT and EBV-latent infection membrane protein-1. In situ hybridization also showed negativity for EBV-encoded small RNA. These findings were histologically compatible with MCL. To our knowledge, this is the first reported case of MCL initially manifesting as a symmetrical mass on the hard palate with osteolysis in such an elderly patient.