Primary pulmonary non-Hodgkin's lymphoma

Primary pulmonary non-Hodgkin's lymphoma is a very rare neoplasm. It is represented most commonly by marginal zone B-cell lymphoma of mucosa-associated lymphoid tissue (MALT) type. Although there have been a few reviews of this lymphoma, clinical features, diagnostic procedure, optimal management and prognostic factors have not been well defined.

We reviewed the medical records of 24 patients who were pathologically and clinically diagnosed as primary pulmonary lymphoma between September 1995 and June 2003.

There were 13 patients with MALT lymphoma and two with MALT lymphoma accompanied by large B-cell lymphoma, seven with diffuse large B-cell lymphoma and two with anaplastic large cell lymphoma. Half the patients were asymptomatic at presentation; 46% had respiratory symptoms and 16.7% had B-symptoms. Initial radiological findings were variable including nodules, masses, infiltrates or consolidation. The majority of patients (66.7%) needed surgical approaches (open thoracotomy or video-assisted thoracoscopy) for definite diagnosis. Bronchoscopy was performed in 83%, but only 30% showed a diagnostic yield. The 13 patients with MALT lymphoma were treated with a variety of modalities such as observation, surgery and single or combination chemotherapy, and combination chemotherapy was administered to 11 patients with non-MALT lymphoma regardless of surgery. The overall survival rate at 3 years for all 24 patients was 86% with a median follow-up of 32 months.

Although this entity of lymphoma appears to have a good prognosis, further clinical experience and long-term follow-up are needed to identify prognostic factors.