Treatment of multifocal lymphoma of bone with intensified ProMACE-CytaBOM chemotherapy and involved field radiotherapy.

Primary bone involvement is an unusual extranodal presentation of non-Hodgkin lymphoma (NHL). The optimal treatment for this entity has not been determined. While solitary bone lymphomas can be eradicated with local radiation in 50% of patients, distant relapses occur frequently, and the treatment of patients with multifocal osseous disease, or those presenting with associated soft tissue invasion or adenopathy is even less satisfactory. Over a 4-year period, nine patients with multifocal bone lymphoma were treated with intensified versions of the ProMACE-CytaBOM regimen and involved-field radiation. Seven patients had diffuse large cell histology and two patients had diffuse mixed type. Seven patients survived event-free at a median follow-up of 2.3 years (range .5-3.5). In most survivors, there was little or no change in the abnormal radiographic bone findings despite the clinical response to therapy. In one patient, magnetic resonance imaging (MRI) established that bone infarction rather than relapse of lymphoma was the cause of a new lytic bone lesion that developed during treatment.