Abstract: Objective :To compare the efficacy and toxicity of CTOP (with THP) and CHOP in thetreatment of unspecified peripheral T-cell lymphoma (PTCL- U). Methods :One hundred and thirty pa-tients with PTCL- U were treated with combined chemotherapy, including CTOP and CHOP, from Jan-uary 1997 to December 2003 in the Cancer Center, among which 49 were treated by CTOP and 81 byCHOP regimen. The rate of response, toxicity and long- term survival for the two regimens were ana-lyzed retrospectively. Results :The clinical characteristics of the two groups were similar (P>0.05). Atotal of 129 patients were eligible. The response rate for CHOP and CTOP was 71.6% and 72.8%, re-spectively (P>0.05) and the CR rate was 43.2% and 39.5%, respectively (P>0.05). Major toxicity wasmyelosuppression, GI toxicity and alopecia. There was no difference between the two groups in gradeⅢ~Ⅳ toxicity in neutropenia, thrombocytopenia and anemia. Incidence of alopecia was higher in theCHOP group (31.1% vs. 14.0%, P=0.000). Although cardiotoxicity was high in CHOP group (11.1% vs.6.1%), no statistical difference between the two groups was confirmed (P=0.522).Median follow-up was24 months (ranged from 1 to 88 months). The 5- year overall survival rate for CHOP and CTOP groupwas 22.0% and 44.2%, respectively (P<0.01). Conclusions :THP in the CTOP regimen may be moreeffective on PTCL- U with lower toxicity and better long term survival. Randomized clinical trial is war-ranted.