Primary diffuse large B-cell lymphoma of the bone: bendamustine and rituximab are able to overcome resistant disease.

Primary bone lymphoma (PBL) is a rare disease for which specific therapeutic guidelines have not yet been established. Due to common appearance in the elderly and recurring relapses, new treatments are required. We report the case of multiple relapsed aggressive PBL effectively treated using Bendamustine and Rituximab. A 78-year-old male patient presented with a painful mass in the left arm. Computed tomography (CT) showed a pathological tissue in the humerus diaphysis infiltrating the muscle, confirmed by positron emission tomography (PET) scan. Indeed, PET excluded pathological local lymph node involvement. Biopsy of the humerus revealed the presence of diffuse large B cell lymphoma. Recommended treatments for PBL were used, but relapses after an initial complete response occurred. Following the positive experience of Vacirca et al. the patient underwent Bendamustin 90 mg/mq gg1-2 q28 plus Rituximab 375 mg/mq q28 (BR). Herein we report the first experience of BR combination in PBL and it proved to be an efficacious and safe salvage therapy in relapsed/refractory PBL.