Peripheral T-cell non-Hodgkin's lymphomas of low malignancy: prospective study of 25 patients with pleomorphic small cell lymphoma, lymphoepitheloid cell (Lennert's) lymphoma and T-zone lymphoma. The Kiel Lymphoma Study Group.

Peripheral T-cell lymphomas comprise a heterogenous group of low- and high-grade malignancies differing in their histopathological appearance and also in clinical and prognostic aspects. We prospectively studied 25 patients with low-grade peripheral T-cell lymphomas: pleomorphic, small cell lymphoma (PSC) (n = 9), lymphoepitheloid (Lennert's) lymphoma (LEL) (n = 12) and T-zone lymphoma (TZL) (n = 4). The median patient age was 55 years (range 19-75 years); the male to female ratio was 1.5. 13 patients (52%) had limited stages (I+II), 12 patients (48%) had advanced disease (stage III+IV). 21 patients received the COPBLAM/IMVP-16 regimen. Two patients received more intensive treatments; two received less intensive therapy. Complete remissions were achieved in 16/25 patients (64%). The median observation time of surviving patients was 30 months (range 5-72 months). The actuarial overall survival and event-free survival at 2 years of 21 patients receiving COPBLAM/IMVP-16 were 69% and 35%, respectively. Intensive chemotherapy led to complete remissions in about 60% of the patients and to long-term disease-free survival for one-third. The observed clinical courses illustrate the aggressive nature of PSC, LEL and TZL.