Primary bone lymphoma: Single institution experience

Abstract

19515 Background: Primary bone lymphoma (PBL) is a rare condition and accounts for less than 2% of all adult lymphomas and 3% of all primary bone malignancies. Presentation is usually in the fifth or sixth decade with limited stage disease. Due to the rarity of this disease there is a lack of prospective randomized clinical trials and hence optimal treatment is unceratin. Methods: Using our hospital database, we identified all patients with PBL, their international prognostic index (IPI) score, treatment, and long-term follow-up. All patients had a bone marrow aspirate and biopsy remote from the primary tumor. Results: From January 1989 to July 2007 we identified 12 patients with PBL. Male to female ratio was 1:1, and median age was 36.5years (range,20–68years). Diffuse large b-cell type (DLBCL) was the most common histology (11 pts). Long extremity bones were the most common presenting sites (femur=4, tibia=1, humerus=1). Multifocal disease was present in three cases and one of these presented with spinal cord compression. Nine patients had stage 1E disease. Pathological fracture was a presenting feature of 5 pts, of which 3 needed surgery first. Treatment modalities included surgery, chemotherapy, and radiotherapy. Chemotherapy was given first in 8 patients and the most common regimen was CHOP (8 pts) with Rituximab added after 2002. Median follow-up is 8 years (range,0.5–18.5 years), and overall and disease free survival is 100%. Conclusions: PBL has a better prognosis than nodal DLBCL and other extranodal lympohomas. Combined modality therapy (CMT), i.e. chemotherapy followed by radiotherapy is the prefered treatment option, despite the lack of prospective randomized clinical trials, unless adverse neurology or an unstable fracture presents first. PET scanning should be used to assess response to treatment. The pathogenesis of bone lesions in PBL is unclear and the use of bisphosphonates and periodic checking of calcium levels should be further explored. Pathological fractures and spinal cord compression, as well as multifocal disease do not confer a worse prognosis. No significant financial relationships to disclose.