ESTRO 2023 - Abstract Book

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ESTRO 2023

interquartile range/range, while categorical variables were presented with absolute and relative frequencies. Toxicities were collected according to RTOG scale and survival curve was calculated with Kaplan-Meier method for biochemical recurrence. Results A total of 108 patients fullfilled inclusion criteria. Among them, 56 (52%) were diagnosed with unfavorable intermediate and 52 (48%) with high-risk PCa. Median age at diagnosis was 80 years (Range 75 - 90) and median PSA at diagnosis was 9.2 ng/ml (Range 1.2-220.4). All patients underwent UHRT on prostate in 5 fx every other day with a dose/fx within 6.5 and 7.25 Gy. The majority of patients (61%) underwent concomitant ADT with a median duration time of 9.0 months (1.0-4.6). General cohort characteristics and reported toxicities are summarized in Table 1 . After a median follow-up of 2.8 years (IQR 1.0-4.3), 21 patients (19.4%) experienced a biochemical recurrence, with a median time to biochemical recurrence of 29.8 months (IQR 20.4 – 42.9). One and 2 years biochemical DFS rates were 99.99% and 99.95%, respectively. Kaplan-Meier survival curve can be seen in . Among the 21 biochemical recurrences, 13 patients (12.0%) developed a clinical progression of disease (10 in high risk and 3 in unfavorable intermediate risk classes). At last censored FU, 65 patients (60.0%) are alive with no evidence of disease, 15 (13.9%) are alive with disease and 18 (16.6%) died. One G2 gastrointestinal (GI) acute toxicity was observed and 6 G2 genitourinary (GU) toxicities were reported. No G ≥ 3 GU/GI acute toxicities were noted. A G2 late toxicity occurred in 2 patients for both GI and GU toxicities. One G3 GU late toxicity was described. All toxicities were solved at last follow-up.

Figure 1