ABSTRACT
Objective: To study the prevalence and characterization of primary non Hodgkin's lymphoma of bone in a major referral center of Pakistan. Methodology: All cases of primary non Hodgkin's lymphoma of bone, diagnosed at a referral center in Pakistan from January 1998 to July 2008 have been included. Patients with diagnosis of lymphoma at some other site prior to diagnosis in bone biopsy were excluded from the study. Results: Sixty cases of primary non Hodgkin's lymphoma of bone were received, with a male to female ratio of 7: 3 (42 males and 18 females). Overall, 52/60 (86.6 %) patients were diagnosed with Diffuse large B-cell non-Hodgkin's lymphoma. The largest fraction of patients was found in the pediatric group i.e. 33/60(55%) followed by elderly group i.e.15/60 (15%) and adults i.e. 12/60 (20%). The commonest sites of involvement were femur (28.3 %), hip bone (16.6%) and humerus (10%). Conclusion: Diffuse large B-cell lymphoma is the commonest type of primary non Hodgkin's lymphoma of bone in the Pakistani population. It is common in all ages. The sites most often involved are femur followed by hip bone. Primary non Hodgkin's lymphoma of bone appears to be more common in males. Our results are comparable to international data with various studies also showing that diffuse large B cell non Hodgkin lymphoma is the commonest primary bone lymphoma. However, primary Bone Lymphoma is more common in children and young adults.