Mantle cell lymphoma involving the oral and maxillofacial region: a study of 20 cases

Objective. To investigate the clinicopathologic features of mantle cell lymphoma (MCL) involving the oral and maxillofacial region. Methods. The MCL cases were retrieved from the pathosis database of 6 pathology laboratories. Original hematoxylin and eosin slides and immunohistochemical reactions were reviewed for confirmation of the initial diagnosis. Clinical data of the cases were obtained from the patients' pathosis and/or medical charts. Results. Twenty cases were included in the study, showing a male predominance and a mean age of 66 years. The oral cavity (12 cases) and the oropharynx (5 cases) were the most commonly involved subsites. Most cases presented as asymptomatic swellings, with 2 cases showing bilateral involvement of the palate. The classic histologic variant predominated (12/20 cases). All cases expressed CD20 with nuclear cyclin D1 positivity. SOX11 was seen in 9/13 cases, CD5 in 6/16 cases, Bcl2 in 16/19 cases, CD10 in 2/20 cases, and Bcl6 in 4/16 cases. Ki67 showed a mean proliferation index of 40.6%. The Epstein-Barr virus (EBV) was negative in all cases investigated. Follow-up data was available for 7 patients, with 5 currently alive and 2 deceased. Conclusion. Mantle cell lymphoma, albeit rare, may manifest in the oral and maxillofacial region. Its histologic heterogeneity demands a high degree of diagnostic skill from pathologists. (Oral Surg Oral Med Oral Pathol Oral Radiol 2023;135:101-109)