Objectives To describe clinicopathologic features and to identify prognostic factors in a large series of primary cutaneous diffuse large B-cell lymphoma, leg type (PCLBCL LT), as defined in the recent World Health Organization–European Organization for Research and Treatment of Cancer classification of cutaneous lymphomas. Design Retrospective multicenter study from the French Study Group on Cutaneous Lymphomas. Setting Nineteen departments of dermatology in 10 regions of France. Patients Sixty patients with a PCLBCL LT included in the registry of the French Study Group on Cutaneous Lymphomas. Main Outcome Measures Age, sex, outcome, therapy, B symptoms, cutaneous extent, number of lesions, location (leg vs nonleg), serum lactate dehydrogenase level, and MUM-1 and Bcl-2 expression were recorded. Disease-specific survival was used as the main end point. Prognostic factors were identified using a Cox proportional hazards model. Results Primary cutaneous diffuse large B-cell lymphoma, leg type is characterized by a predilection for the leg (72%), a high proportion of Bcl-2 expression (85%), an advanced age at onset (mean age, 76 years), and frequent relapses and extracutaneous dissemination. The overall 5-year disease-specific survival rate was 41%. Location on the leg and multiple skin lesions were predictive of death in multivariate analysis. Although no variable related to therapy was significantly associated with survival, patients recently treated with combinations of anthracycline-containing chemotherapies and rituximab had a more favorable short-term outcome. Conclusions Primary cutaneous diffuse large B-cell lymphoma, leg type is a distinct entity with a poor prognosis, particularly in patients with multiple tumors on the legs. Despite the advanced age of many patients, the prognosis could be improved with combinations of anthracycline-containing chemotherapies and rituximab.
