Autologous stem cell transplant for relapsed and refractory peripheral T-cell lymphoma: variable outcome according to pathological subtype Kevin W. Song, Peter Mollee, Armand Keating and Michael Crump University of Toronto Autologous Blood and Marrow Transplant Program, Princess Margaret Hospital, Toronto, Ontario, Canada Received 19 August 2002; accepted for publication 28 October 2002 Summary. The purpose of this study was to evaluate the outcome of high-dose chemotherapy (HDCT) followed by autologous haematopoietic stem cell transplant (ASCT) for patients with relapsed T-cell non-Hodgkin’s lymphoma. We reviewed 36 patients with peripheral T-cell lymphoma (PTL) who underwent ASCT between January 1987 and June 2001. Patients had chemosensitive disease, and received high-dose melphalan and etoposide with or without total body irradiation supported by unpurged autologous stem cells. Comparisons were made with 97 diffuse large B-cell lymphoma (DLBL) patients. PTL patients had a median age of 46 years (19–62 years). Twenty-nine had relapsed and seven had primary refractory disease. DLBL patients were statistically similar in baseline characteristics. Of patients with PTL, six (17%) died of treatment-related complications and 14 (39%) were in remission with a median follow-up of 42 months (range 6–116 months). Three-year overall survival and event-free survival (EFS) were 48% and 37%, respectively, for PTL, compared with 53% and 42% for DLBL (P ¼ 0Æ41 and 0Æ29 respectively). There was no significant prognostic variable found by univariate analysis for the PTL cohort. Major PTL subtypes were analysed for outcomes. The 20 patients with PTL, not otherwise specified (PTL-NOS), had an inferior EFS compared with DLBL patients (23%, P ¼ 0Æ028). In contrast, the nine patients with anaplastic large T/null cell lymphoma had a non-significant trend for improved EFS (67%, P ¼ 0Æ41). While ASCT in patients with relapsed or primary refractory PTL results in long- term remission rates comparable to DLBL patients, those with PTL-NOS do significantly worse. Keywords: peripheral T-cell lymphoma, autologous stem cell transplantation, pathology, relapse. The recognition of new lymphoma subtypes with improved diagnostic techniques and prognostic indicators has led to the development of the Revised European–American Lym- phoma (REAL) classification which was recently updated as the WHO lymphoma classification (Harris et al, 1994, 1999). In these classifications, T-cell lymphomas are considered separately from B-cell lymphomas, reflecting the importance of immunophenotypic analysis when clas- sifying disease and determining prognosis. Although there is a regional variation in incidence, T-cell lymphoma has been found to account for between 8% and 15% of all non- Hodgkin’s lymphomas (NHLs) (Anonymous, 1997; Melnyk et al, 1997). It has also been shown that, in general, patients with peripheral T-cell lymphoma (PTL) have a significantly worse outcome compared with patients with aggressive histology B-cell lymphomas. Gisselbrecht et al (1998) reviewed the Groupe d’Etude des Lymphomes de l’Adulte (GELA) experience of treating patients with diffuse aggressive NHL enrolled in the lymphoma protocol LNH 87 study. Five-year overall survival (OS) and event-free survi- val (EFS) for B-cell NHL and T-cell NHL were found to be 53% vs 41% (P ¼ 0Æ004) and 42% vs 33% (P <0Æ0001) respectively. Melnyk et al (1997) reported similar differences in long-term results. Patients with advanced-stage aggressive B-cell lympho- mas (diffuse large cell and its variants) can achieve a 30– 50% long-term disease-free survival (DFS) after receiving anthracycline-based chemotherapy (Armitage, 1993). For those who either relapse after or fail induction chemo- therapy, treatment with high-dose chemotherapy (HDCT) followed by an autologous haematopoietic stem cell trans- plant (ASCT) can result in long-term DFS. In the random- ized trial conducted by Philip et al (1995), 46% of patients Correspondence: Dr Michael Crump, The Princess Margaret Hospi- tal Suite 5–108, 610 University Avenue, Toronto, Ontario, M5G 2M9, Canada. E-mail: Michael.Crump@uhn.on.ca British Journal of Haematology, 2003, 120, 978–985 978 Ó 2003 Blackwell Publishing Ltd