Objectives: To evaluate long-term outcomes, impact of maintenance therapy and potential curability of patients with mycosis fungoides (MF) treated with psoralen plus UV-A (PUVA)-monotherapy. Design: Single-center retrospective cohort analysis. Setting: Academic referral center for cutaneous lymphoma. Patients: A total of 66 of 104 patients with clinical stages IA to IIA MF who achieved complete remission (CR) after PUVA monotherapy between 1979 and 1995. Main Outcome Measures: Kaplan-Meier actuarial survival and disease-free survival curves were compared between stage IA and IB/IIA cases. Patients were stratified into relapse and nonrelapse groups based on whether their MF relapsed during study follow-up. Baseline characteristics and treatment were compared between these groups. Results: Median follow-up time was 94 months (range, 5-242 months). Thirty-three patients maintained CR for 84 months (range, 5-238 months), and 33 patients experienced relapse with a median disease-free interval of 39 months (range, 2-127 months). There was no significant difference in baseline characteristics between patients in the nonrelapse and relapse groups. Those in the nonrelapse group received a higher cumulative dosage to CR (P=.03) and required longer treatment periods to achieve CR (P=.03). Disease free survival rates at 5 and 10 years for all patients with stage IA were 56% and 30% , respectively, and for stage IB/IIA, 74% and 50% . Actuarial survival rates at 5, 10, and 15 years were 94% , 82% , and 82% , respectively, in patients with stage IA, and 80% , 69% , and 58% in patients with stage IB/IIA. The overall survival rate for the nonrelapse and relapse groups did not show any statistical difference. One third of the patients developed signs of chronic photodamage and secondary cutaneous malignancies. Conclusions: Psoralen UV-A is an effective treatment for MF, inducing long term remissions and perhaps in some cases disease “ cure.” Thirty percent to 50% of patients remain disease free for 10 years, but late relapses occur. Long-term survival is not affected by relapse status, and the risk of photodamage needs to be measured against the possible benefit of greater disease elimination. Objectives: To evaluate long-term outcomes, impact of maintenance therapy and potential curability of patients with mycosis fungoides (MF) treated with psoralen plus UV-A (PUVA) -monotherapy. Design: Single-center retrospective cohort analysis. center for cutaneous lymphoma. Patients: A total of 66 of 104 patients with clinical stages IA to IIA MF who achieved complete remission (CR) after PUVA monotherapy between 1979 and 1995. Main Outcome Measures: Kaplan-Meier actuarial survival and disease-free survival ups were compared between stage IA and IB / IIA cases. Patients were stratified into relapse and nonrelapse groups based on whether their MF relapsed during study follow-up. Results: Median follow-up time was 94 (range, 5-242 months). Thirty-three patients maintained CR for 84 months (range, 5-238 months), and 33 patients experienced relapse with a median disease-free interv There was no significant difference in baseline characteristics between patients in the nonrelapse and relapse groups. Those in nonrelapse group received a higher cumulative dosage to CR (P = .03) and required longer treatment periods to achieve CR (P = .03). Disease free survival rates at 5 and 10 years for all patients with stage IA were 56% and 30%, respectively, and for stage IB / IIA, 74% and 50%. Actuarial survival rates at 5, 10, and 15 years were 94%, 82%, and 82%, respectively, in patients with stage IA, and 80%, 69%, and 58% in patients with stage IB / IIA. survival rate for the nonrelapse and relapse groups did not show any statistical difference. One third of the patients developed signs of chronic photodamage and secondary cutaneous malignancies. Conclusions: Psoralen UV-A is an effective treatment for MF, inducing long term remissions and perhaps in some cases disease “cure.” Thirty percent to 50% of patients rema-disease free for 10 years, but late relapses occur. Long-term survival is not affected by relapse status, and the risk of photodamage needs to be measured against the possible benefit of greater disease elimination.