A Highly Curable Lymphoma Occurs Preferentially in the Proximal Tibia of Young Patients

The presentation of two 19 year old males with stage I non-Hodgkin lymphoma in the proximal tibia prompted an extensive review of institutional and national databases to assess if there is any statistical evidence that these reflected a previously overlooked syndromic pattern of presentation. The institutional records of a single institution were reviewed for presentation of non-Hodgkin lymphoma in bone. The records of two additional institutions were reviewed for all reports of non-Hodgkin lymphoma in the tibia. Analysis was performed on data from SEER (Surveillance, Epidemiology, and End Results) dichotomized to bone presentation in the lower extremity versus other bones. Institutional databases included 20 patients with tibial presentation of lymphoma with a median age of 22.5 years (versus 42 for all bone lymphomas; p<0.001). 18/20 were diffuse large B cell lymphoma, and all patients ≤ 40 achieved remission and apparent cure. Distinctive and unusual features were a tendency for bilateral involvement of the tibia and sclerotic changes on X-ray. SEER data included 808 cases of bone lymphoma; the fraction of cases presenting in the lower extremity vs other bone sites is higher at ages ≤ 40 years (38% vs 19%; p < 0.0001). Presentation in the lower extremity, as compared to other bone sites, confers 97% overall survival in patients ≤ 40 (vs. 82%; p = 0.01). This survival effect was independent of stage. In contrast, no significant difference in overall survival was identified for lower extremity versus non-lower extremity site for age > 40. These data show a previously undescribed syndromic pattern of disease presentation: bone lymphoma in young patients is likely to present in the lower extremity, specifically the proximal tibia, has atypical sclerotic features on x-ray, is often bilateral, and has an excellent prognosis compared to bone lymphomas at other sites matched for stage and age.