A clinicopathological retrospective study of 131 patients with primary bone lymphoma: a population-based study of successively treated cohorts from the British Columbia Cancer Agency.

BACKGROUND Primary bone lymphoma (PBL) is a distinct clinicopathological entity. Although PBL has been reviewed in several small studies, few reflect recent improvements in primary treatment. METHODS We used the British Columbia Cancer Agency Lymphoid Cancer Database to identify all patients with PBL (1983-2005). All were staged in a uniform manner and treated with era-specific protocols. RESULTS We identified 131 patients with a median age of 63 years (18-87). One third had disease in long bones and another one third had disease in the spine, of which half presented with spinal cord compression. Patients with diffuse large-cell lymphoma (DLCL) (n=103, 79%) had 5- and 10-year overall survivals (OS) of 62% and 41%, respectively. Multivariate analysis identified three prognostic groups: age<60 with International Prognostic Index (IPI) 1-3 (n=43), age>or=60 with IPI 0-3 (n=23) and age>or=60 with IPI 4-5 (n=33), with markedly different 5-year OS of 90%, 61% and 25%, respectively (P<0.0001). Neither primary site nor pathological fracture at presentation had an impact on OS. The 3-year progression-free survival in patients who received rituximab plus combination chemotherapy with cyclophosphamide, doxorubicin, vincristine and prednisone (CHOPR) chemotherapy was 88% compared with 52% in those who received CHOP-like chemotherapy without rituximab (P=0.005). The 10-year OS for those with advanced-stage disease who received irradiation plus chemotherapy was 25% versus 56% for those who received chemotherapy alone (P=0.025). Patients received irradiation if spinal cord compression was present or residual disease at the end of chemotherapy was thought to require it. CONCLUSIONS PBL is usually of DLCL type and has an improved outcome with CHOPR. Younger patients with good IPI score have a favorable prognosis.