Primary Cutaneous B-Cell Lymphoma: Review and Current Concepts

Abstract

PURPOSE: Primary cutaneous B-cell lymphoma (PCBCL) has only recently been recognized as a distinct clinical entity. With the advent of improved immunophenotyping and immunogenotyping, increasing numbers of PCBCL cases are being diagnosed. However, there is much confusion regarding the classification, treatment, and prognosis of these patients. The purpose of this article is to review and analyze the available data to provide the clinician with a concise summary of the diagnosis, prognosis, and treatment of PCBCL. DESIGN: We conducted a thorough review of the medical literature on PCBCL, with a focus on classification, prognosis, and treatment trials. RESULTS AND CONCLUSION: PCBCL is defined as a B-cell lymphoma originating in the skin. There is no evidence of extracutaneous disease at presentation and for 6 months after diagnosis, as assessed by adequate staging procedures. Currently, the European Organization for Research and Treatment of Cancer classification is the most concise disease classification scheme, dividing the subtypes of PCBCL by clinical behavior and histopathologic findings. Based on this classification, the most common subtype of PCBCL is follicular center cell lymphoma. PCBCL is generally an indolent form of lymphoma with a good prognosis. Although local cutaneous recurrences are observed in 25% to 68% of patients, dissemination to internal organs is rare. Five-year survival rates typically range from 89% to 96%. A specific subtype, large B-cell lymphoma of the leg, is noted to have a poorer prognosis, with a 5-year survival rate of 58%. Overly aggressive treatment of PCBCL has not been shown to improve survival or prevent relapse. The treatment of choice usually varies depending on the type of PCBCL, the body surface area, and the location of the involvement, as well as the age and general health condition of the patient. The majority of studies indicate that PCBCL is highly responsive to radiation therapy. Polychemotherapy should be reserved for involvement of noncontiguous anatomic sites or those with extracutaneous spread.