Localised lymphoma of bone: prognostic factors and treatment recommendations. The Princess Margaret Hospital Lymphoma Group.

Twenty seven adult patients with newly diagnosed non-Hodgkin's lymphoma localised to either bone (Stage IE) or bone and regional lymph nodes (Stage IIE) were treated between 1967 and 1988. Median age was 53 years and the commonest histology (21 patients) was diffuse histiocytic lymphoma. Twenty-four patients were treated radically: 15 with radiation therapy (XRT) alone and nine with chemotherapy plus radiation therapy (CMT). The cause specific survival for these patients was 56% at 5 years and 40% at 10 years. Survival was significantly better for patients treated by CMT (88% at 5 years) as compared to XRT alone (40% at 5 years, P = 0.03) and for age less than 60 (72% at 5 years) compared to greater than or equal to 60 (30% at 5 years, P = 0.018). Relapse-free rate was 27% at 5 years with XRT alone and 89% with CMT (P = 0.01). Risk factors for loco-regional relapse (seven cases) included: large tumour bulk, treatment by XRT alone and use of 'limited' radiation fields. No radiation dose-response relationship could be identified in this study. Long term local control and survival for localised lymphoma of bone were excellent after treatment by CMT but XRT alone was associated with unacceptably high local and distant failure rates.