Improving disease-specific survival for patients with Sezary syndrome in the modern era of systemic therapies.

Traditionally, Sezary syndrome (SS) has been associated with few therapeutic options and poor prognosis, with 5-year disease-specific survival (DSS) less than one-third in historical cohorts. However, newer therapies and combinations are associated with impressive time-to-next-treatment (TTNT), particularly allogeneic stem-cell transplantation (AlloSCT) and combination therapies notably those including extracorporeal photopheresis. In this multicentre, international study, we explored the prognostic outcomes of 178 patients exclusively managed for SS, diagnosed between 2012 and 2020, and treated in the modern therapeutic era. In this cohort, 58 different therapies were delivered, with 13.5% of patients receiving AlloSCT. Long-term survival exceeded historical reports with 5-year DSS and OS of 56.4% and 53.4% respectively. In those receiving AlloSCT, prognosis was excellent: 5-year DSS and OS were 90.5% and 78.0% respectively. Confirming the results from the Cutaneous Lymphoma International Consortium (CLIC), LDH and LCT had significant prognostic impact. Unlike earlier studies, stage did not have prognostic impact; we speculate that greater relative benefit favours patients with extensive lymphomatous nodal disease (Stage IVA2) compared to historical reports. For patients ineligible for AlloSCT, the prognosis remains relatively poor (5-year DSS 51.4% and OS 49.6%), representing ongoing unmet needs for more effective novel agents and investigation of improved therapeutic combinations.

International study of treatment efficacy in SS shows superiority of combination therapy and heterogeneity of treatment strategies.

Despite increasing availability of therapies, patients with Sezary syndrome (SS) commonly endure multi-line treatment journeys, mostly with partial responses of short duration. Measuring clinical benefit is challenging; time-to-next-treatment (TTNT) provides a robust, objective measurement of efficacy. This international observational study examines patterns of clinical care and therapeutic benefit as measured by TTNT. TTNT was calculated for monotherapies and combination therapies, with consideration to treatment line. 178 patients with SS (73% de novo, 27% secondary) were included, receiving 721 lines of systemic therapy, with median follow-up of 56.9 months. Across all lines, 58 different therapeutic regimens were prescribed (54 were systemic therapies) and classified into 17 treatment groups. The most common first-line treatments were extracorporeal photopheresis (ECP)-containing combination therapy (20%) and retinoid monotherapy (19%). Median TTNT for all first-line therapies was short (5.4 months). First-line, combination therapies had longer median TTNT than monotherapies, 10.0 vs 5.0 months (P = .004), respectively. Later delivery of combination therapies was associated with shorter clinical benefit, with median TTNT reduced to 6.2 and 2.2 months for mid-line (2nd-4th line) and late-line (≥5th line), respectively (P < .001). First-line ECP-containing treatments were associated with longer median TTNT than non-ECP-containing treatments, 9.0 vs 4.9 months (P = .007). For both ECP-monotherapy and ECP-containing combination therapy, significant reductions in TTNT were seen in later lines. These data suggest therapeutic benefit from first-line delivery of combination therapy for SS and favor early inclusion of ECP in the treatment algorithm for those who can access it.