Lack of durable disease control with chemotherapy for mycosis fungoides and Sézary syndrome: a comparative study of systemic therapy.

Numerous systemic treatment options exist for patients with mycosis fungoides (MF) and Sézary syndrome (SS), but no large comparative studies are published. To study the efficacy of treatments, a retrospective analysis of our cutaneous lymphoma database was undertaken, with 198 MF/SS patients undergoing systemic therapies. The primary end point was time to next treatment (TTNT). Patients with advanced-stage disease made up 53%. The median follow-up time from diagnosis for all alive patients was 4.9 years (range 0.3-39.6), with a median survival of 11.4 years. Patients received a median of 3 lines of therapy (range 1-13), resulting in 709 treatment episodes. Twenty-eight treatment modalities were analyzed. The median TTNT for single- or multiagent chemotherapy was only 3.9 months (95% confidence interval [CI] 3.2-5.1), with few durable remissions. α-interferon gave a median TTNT of 8.7 months (95% CI 6.0-18.0), and histone deacetylase inhibitors (HDACi) gave a median TTNT of 4.5 months (95% CI 4.0-6.1). When compared directly with chemotherapy, interferon and HDACi both had greater TTNT (P < .00001 and P = .01, respectively). This study confirms that all chemotherapy regimens assessed have very modest efficacy; we recommend their use be restricted until other options are exhausted.