The role of high dose chemotherapy (HDC) and stem cell transplant (SCT) in peripheral T-cell lymphoma (PTCL) was studied in 28 patients, from 1988 to 2002. The aim was to determine if subsets recognized by the REAL/WHO classification have different prognoses. Outcome was compared to 86 patients with diffuse large B-cell lymphoma (DLBCL) transplanted during 1986-2000. The 3-year overall survival (OS) and event free survival (EFS) were 69% and 50%. Patients with anaplastic large cell lymphoma (ALCL) had a better 3-year OS compared to those with non-ALCL histology (86% vs. 47%, P=0.0122). Anaplastic lymphoma kinase (ALK)- positive ALCL patients had a superior EFS compared to ALK-negative ALCL (100% vs. 0; P=0.0228). Patients with cutaneous ALCL (ALK-negative) relapsed, but had an indolent course after SCT. Low International Prognostic Index score at relapse predicted for a better 3-year OS (85% vs. 34%, P=0.0238). When compared to DLBCL, patients with ALCL had a superior OS (86% vs. 36%, P=0.0034) and patients with non-ALCL had a comparable OS. ALCL histology confers better survival compared to non-ALCL and DLBCL histologies. ALK-positive ALCL is associated with the best EFS after relapse with HDC and SCT. The timing of SCT for non-ALCL histology remains to be determined.