Most common cutaneous T-cell lymphomas (CTCL) are Mycosis fungoides (MF) and a leukemic, erythrodermic (E) variant known as Sézary Syndrome (SS). Blood (B) criteria were not previously considered for staging purposes and are evolving. E-CTCL can be divided into E-MF versus SS based on new criteria, B0-B2, published by the ISCL guidelines. Historically, overall survival (OS) of “SS” patients is 2–4 years. To determine if hematologic staging and prognostic variables affects overall survival, we retrospectively studied 1197 MF/CTCL patients seen at MDACC since 1987 from which were identified 124 (10%) patients with E-CTCL. Median age at diagnosis was 63 (range 0–89), 71 males and 53 females. Hematologic (H) stage was based on quantitative Sézary cell counts (manual or by flow as absolute CD4+26−). Overall survival curves were estimated by Kaplan and Meier and compared using log-rank tests. Median OS all 124 E-CTCL patients was 5.1 years [range=0.4–18.6]. We also considered patients divided by the H0–H4 staging system (Russell-Jones 2000). For H0–H2, OS was 7.6 years, H3 was 5.4 years, and H4 was 2.4 years (p=0.011). Treatment with systemic steroids, advanced age, increased serum LDH at presentation, WBC > 20,000 were significant prognostic factors. Large cell transformation (p=0.758), positive T-cell receptor gene rearrangement in the skin (p=0.54), stage of disease (p=0.955), prior exposure to multiple treatments (p=0.953), and CD4:CD8 ratio (p=0.068) were not significant. In conclusion, we provide evidence that absolute Sézary cell counts can be used to define three groups of patients with E-CTCL with different overall survival patterns and propose a modification to the ISCL B ratings as follows: B0, absolute Sézary cell count < 1.0 KuL−1; B1: absolute Sézary cell count ≥ 1.0–10.0 KuL−1; and B2: absolute Sézary cell count >10.0 KuL−1. Serum LDH and CD4/8 ratio may be used to estimate tumor burden, as they correlate with Sézary counts.
Disclosure: No relevant conflicts of interest to declare.