High clinical response rate of Sezary syndrome to immunomodulatory therapies: prognostic markers of response.

Objectives: To quantify response rates of Sézary syndrome (SS) to multimodality immunomodulatory therapy and to identify the important prognostic parameters that affect overall response to treatment.

Design: Retrospective cohort study.

Setting: Cutaneous T-cell lymphoma clinic at The Hospital at the University of Pennsylvania.

Participants: Ninety-eight patients who met the revised International Society for Cutaneous Lymphomas (ISCL) and the European Organization of Research and Treatment of Cancer (EORTC) criteria for the diagnosis of SS and were seen over a 25-year period at the University of Pennsylvania. Intervention Patients were treated with at least 3 months of extracorporeal photopheresis and 1 or more systemic immunostimulatory agents.

Main Outcome Measures: Overall response to treatment was the main measurement of outcome.

Results: A total of 73 patients had significant improvement with multimodality therapy: 30% had complete response, with clearing of all disease (n = 29), and 45% had partial response (n = 44). At baseline, the complete response group had a lower CD4/CD8 ratio than the nonresponse group (13.2 vs 44.2) (P = .04) and a lower median percentage of CD4(+)/CD26(-) cells (27.4% vs 57.2%) (P = .01) and CD4(+)/CD7(-) cells (20.0% vs 41.3%) (P < .01). Median monocyte percentage at baseline was higher for patients who had a complete response than for nonresponders (9.5% vs 7.3%) (P = .02). The partial response group did not have any statistically significant variables compared with the nonresponse group.

Conclusions: In this large cohort study of patients with SS, a high clinical response rate was achieved using multiple immunomodulatory therapies. A lower CD4/CD8 ratio, a higher percentage of monocytes, and lower numbers of circulating abnormal T cells at baseline were the strongest predictive factors for complete response compared with nonresponse and warrant further examination in a larger cohort.