ESTRO 2024 - Abstract Book

S1164

Clinical - Haematology

ESTRO 2024

One hundred and thirty patients (p.) with pathologically confirmed MF/SS were treated with TSEBT between 1982 and 2019. We retrospectively analyzed 117 p. for whom a clinical response was available. Mean age: 54 years (range 26-84); male/female 79/38; stage: I 59 p. (50.4%), II 25 p. (21.4%), III 19 p. (16.2%) and IV 14 p. (12%). A total of 99 p. (84.6%) received an average of three lines of treatment prior to irradiation. TSEBT was delivered using the modified Stanford six-field technique with a 6 MeV electron beam; median dose: 30 Gy, 4 days/week, for 6 weeks. Most patients received supplemental boosts (10-15 Gy) in shadowed areas. Statistics: Chi square test, Kaplan Meier, long rank test.

Results:

Median follow-up: 75 months (range 1-394). One month after TSEBT, 85 p. (72.6%) and 23 p. (19.7%) achieved a complete and partial response, respectively. The cutaneous complete response rate was lower in stage IV (29% vs 76%, 88% and 73% for stages I, II and III respectively; p=0.013). Twenty-three p. died; 13 deaths (56%) were related to tumour progression or complications from any of the treatments received, and 8 (6.8%) and 2 (1.7%) deaths were attributed to other or unknown causes, respectively. Survival rates were better in early stage disease (83%, 88% and 84% for stages I, II and III respectively vs. 42% for stage IV; p=0.004). For the overall group, the 5-, 10- and 20-year actuarial overall survival (OS) were 82%, 74% and 57%, respectively (Figure 1). According to stage, 5- and 10-year actuarial OS were: 84% and 79% for stage I; 95% and 85% for stage II; 87% and 73% for stage III; 40% and 20% for stage IV, respectively (Figure 2). Seventy-six patients (65%) relapsed at a median time of 46 months (range 1-348). The most common acute side effects were erythema, temporary alopecia, ocular lesions, feet edema, and nail disorders. No severe acute or chronic toxicity was observed.