Extranodal Head and Neck Mantle Cell Lymphoma: Characteristics, Treatment, and Survival

Objectives: To describe disease characteristics and treatment and to analyze survival and mortality for extranodal mantle cell lymphoma (MCL) of the head and neck. Methods: Patients with extranodal MCL-excluding primary sites in the salivary glands, eye, and adnexa-were identified from the Surveillance, Epidemiology, and End Results (SEER) 18 Registries (2000-2015). Overall survival (OS) and cumulative incidence of MCL and non-MCL mortality were calculated. Factors associated with MCL and non-MCL mortality were analyzed with cause-specific hazard models. Results: Five hundred nine patients met criteria for descriptive analysis and 294 patients met criteria for survival analysis, with a median follow-up of 58 months. The most common sites for MCL were the oropharynx (66.0%), nasopharynx (19.1%), and oral cavity (8.4%). The most common treatment received was chemotherapy alone (48.9%), followed by chemoradiation therapy (16.9%), and radiation therapy alone (10.4%). The proportion of cases diagnosed as early-stage disease ranged from 31% of sinonasal MCLs to 83% of laryngeal MCLs. At 5 years, OS was 63% (95% CI: 57%-69%). There was no significant difference in OS (P = .79), cumulative incidence of MCL mortality (P = .76), or cumulative incidence of non-MCL mortality (P = .98) by anatomic site. Comparing early-stage to late-stage disease, there was no significant difference in OS (P = .38), cumulative incidence of MCL mortality (P = .07), or cumulative incidence of non-MCL mortality (P = .14). Multivariate analysis showed increased hazard of MCL mortality for patients that were older or that presented with stage III or stage IV disease. Conclusion: The oropharynx is the most common subsite of head and neck MCLs, followed by the nasopharynx. Primary head and neck MCLs appear to present at an earlier stage than MCLs of other regions. In particular, laryngeal and hypopharyngeal MCLs may present as stage I or II disease.