ESTRO 2025 - Abstract Book

S1687

Clinical - Sarcoma & skin cancer & malignant melanoma

ESTRO 2025

metastasis. In multivariate analysis, age (hazard ratio: 1.72; 95% CI: 1.10-2.69), size category (hazard ratio: 1.77; 95% CI: 1.30-2.42), ciliary body adjacent (hazard ratio: 1.87; 95% CI: 1.03-3.40) and papilla adjacent (hazard ratio: 1.73; 95% CI: 1.03-2.90) were significant. Conclusion: Predictive factors associated with distant metastatic recurrence after carbon-ion radiotherapy for choroidal melanoma were identified. Our findings suggest that systemic imaging evaluation during follow-up is crucial, particularly for elderly patients, those with large tumors, and patients with tumors adjacent to the ciliary body or papilla. Though those without still possess a rather high distant metastasis rate, implicating the need to explore more predictive factors.

Keywords: choroidal, distant metastasis, carbon-ion

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Digital Poster CONTACTHERAPY 50 KV FOR CARCINOMA OF THE EYELID: REPORT AT 8 YEARS OF 73 CASES Nina Pujol 1 , Tanguy Pace-Loscos 2 , Renaud Schiappa 2 , Deborah Aloi 1 , Maud Leguyader 1 , Henri Montaudié 3 , Agathe Villarmé 4 , Jérôme Doyen 1 , David Baron 1 1 Departement of Radiation Oncology, Antoine Lacassagne Cancer Centre, Nice, France. 2 Departement of Biostatistics, Antoine Lacassagne Cancer Centre, Nice, France. 3 Departement of Dermatology, CHU de Nice, NIce, France. 4 Departement of Head and Neck Surgery, Antoine Lacassagne Cancer Centre, Nice, France Purpose/Objective: We report a retrospective series of 73 carcinoma of the eyelid treated by contact x-ray therapy (CXT) at Antoine Lacassagne Center. Material/Methods: All patients were treated at our center from February 2009 to December 2018, using a Philips RT 50 unit delivering a 50 kV maximum energy X-ray beam. Out of a total of 70 patients, 3 had two synchronous treated tumors. The age range was from 35 to 96 years (median: 82.2 years). The sex distribution was 44% male and 56% female. Tumor localization was: 8.2% in the lateral canthus, 45.2% in the medial canthus, 32.9% in the lower eyelid, and 13.7% in the upper eyelid. Histological diagnoses included 74% basal cell carcinoma, 15% squamous cell carcinoma, and 4.1% melanoma. We mostly treated small lesions: 41.5% were < 10 mm, 50.8% were between 10 and 20 mm, and only 7.7% were > 20 mm. A total of 82.2% of patients were referred for post-operative treatment (R1 excision or R0 with poor histoprognostic factors and contraindications for further surgery), while 16.1% received radical radiotherapy. Patients were treated according to two regimens: 42 Gy in 6 fractions (32.8%) for radical treatment, and 35 Gy in 5 fractions (67.2%) for post-operative treatment.

Results: