Primary mediastinal large B-cell lymphoma: clinical study of a distinct clinical entity and treatment outcome in 20 patients: review of the literature.

Primary mediastinal B-cell lymphoma (PMBCL) is a discrete subset of large B-cell lymphoma with unique clinicopathologic features. The question of optimal treatment emerges because it is an uncommon but not rare occurrence. A retrospective study was therefore conducted in a group of patients in Greece to evaluate the clinical features and treatment outcome in this disease. Twenty patients with PMBCL, with a median age of 42 years, treated at centers participating in the Hellenic Cooperative Oncology Group over the last 20 years, were reviewed. Thirteen (65%) had bulky disease at the time of presentation, 7 (35%) had superior vena cavae obstruction, and 15 (75%) had extranodal involvement. All received doxorubicin-containing chemotherapy, followed in 11 cases by mediastinal radiotherapy. With a median follow-up of 91 months, the median survival is 67.7 months. These data are consistent with those reported from other centers concerning the patient's characteristics, natural history, response pattern to chemoradiation therapy, and prognosis. Response to therapy proved of prognostic significance. A key question that remains is the prompt identification of patients who would benefit from innovative or more intensive therapies.