Pulmonary marginal zone lymphoma: a single centre experience and review of the SEER database.

Pulmonary marginal zone lymphoma is a rare disease arising from bronchial-associated lymphoid tissue (BALT). There is limited information on clinical presentation, natural history and treatment of this type of lymphoma. We conducted a retrospective review of patients with biopsy-proven BALT lymphoma treated at our institution and patients from the surveillance epidemiology and end results (SEER) database. Twenty-one patients (median age 57) with disease stage IE (n=10) and IV (n=11), were treated at our institution. Initial management included observation (n=4), surgery (n=5), combination chemotherapy (n=7), single-agent rituximab (n=3) and radioimmunotherapy (n=2). Complete remission was observed in 10, partial remission in 3, stable disease in 7, and disease progression in 1 patient. With a median follow-up of 20 months, Kaplan-Meier estimates for progression-free and overall survival (OS) at 80 months were 90% and 95%, respectively. We identified 326 patients (59% females and 41% males; median age 68 [30 to 85) with BALT lymphoma in the SEER database. Fifty-five per cent had stage IE, 10% stage IIE, 3% stage IIIE, and 22% stage IV disease. After a median follow-up of 35 months, median OS was 112 months, and disease-specific median survival was not reached. At 90 months, disease-specific survival was 85% (CI 77-92) with no significant differences in outcome between patients presenting with different stages. Our single institution experience and review of the SEER database, confirm the indolent features and favourable outcome of this rare disease.