IUC24415-81 Clinical outcomes in stage I seminoma patients aged ≥ 45 years according to treatment modality

Abstract Background Data regarding progression-free (PFS) and overall survival (OS) in clinical Stage I (CSI) seminomatous germ-cell tumors (SGCT) patients older than 45 years are limited. We address this knowledge gap, testing for these clinical outcomes according to treatment modalities within retrospective multicenter real-world data from 3 Italian institutions. Methods Data from patients aged ≥ 45 years diagnosed with testicular CSI SGCT between 01/1992 and 07/2023 were collected. Descriptive analyses were performed and Kaplan–Meier curves were used to assess PFS and OS according to treatment modality, consisting of active surveillance AS vs adjuvant chemotherapy CHT: 1 course of carboplatin AUC 7 vs adjuvant radiotherapy RT: 20 to 30 Gy as paraortic strip or paraortic plus ipsilateral iliac nodes. Results A total of 182 patients were selected. Of those, 120 (65%) underwent AS, 45 (25%) CHT, and 17 (10%) RT. Overall median age was 49.6 years (IQR 46.4-54.6). Patients undergoing AS were older (50.2 yo, IQR 47.2-55.3) than patients undergoing CHT (49.3 yo, IQR 46.4-51.3) or RT (49.3 yo, IQR 45.1-49.7). Most patients (98/182 or 54%) were aged between 45 and 50 years: 59 (60%), 27 (28%), and 12 (12%) underwent AS, CHT, and RT, respectively. Patients aged 51-65 were 74 (41%): 52 (70%), 18 (25%), and 4 (5%) underwent AS, CHT, and RT, respectively. Ten patients (5%) were aged 65: 9 underwent AS and 1 RT. (Table 1). After a median follow-up of 60 months, 5-year PFS was 83.7% for AS, 91.7% for CHT and 76.5% for RT (P = .41) (Figure 1). Relapses occurred in 18 (15%) vs 4 (9%) vs 5 (29%) patients in AS vs CHT vs RT, respectively. After a median follow-up of 60 months, 5-year OS was 100% across all treatment groups (P = .47). Conclusions In CSI SGCT patients aged over 45, outcomes were excellent and aligned with the general CS I SGCT population, with 5-year PFS differences among treatment groups not reaching statistical significance. All relapsed patients were cured, and the 5yrs OS reached 100%. These results confirm the favorable prognosis of CSI SGCT even in older men.