ESTRO 2022 - Abstract Book

S1185

Abstract book

ESTRO 2022

Materials and Methods In this prospective study, 96 patients with localized prostate cancer were included from Sep. 2019 to Sep. 2021. The most of them (83 patients) were treated with a hypofractionated RT of prostate (60 Gy with 3 Gy single dose), eight patients were treated with normofractionated RT with 70 - 76 Gy dose and five with ultra-hypofractionated RT (5 x 7.25 Gy, 3 fractions per week). EORTC QLQ-C30 and -PR25 questionnaires were fulfilled before RT, on the last day of RT, three months after RT and one year after RT, respectively. Diverse functional scores (100 for the best and 0 for the worst function) and symptom scores (100 for the strongest and 0 for no symptoms) were calculated at each time point. Moreover, the changes of these scores were evaluated. Results In general, QLQ-C30 and -PR25 functional scores before RT were satisfactory except sexual activity, probably due to the old age (median 78). QLQ-C30 and –PR25 symptom scores were low, except fatigue, insomnia and urinary symptoms. At RT end, there was a slight to moderate decline of all functional scores and an increase of all symptom scores, except financial difficulties (FD), which stayed stable. Three months after RT, nausea/vomiting, dyspnoe and FD stayed stable and hormonal treatment-related symptoms (HTR) went even worse, while the other functional and symptom scores recovered partially (pain, diarrhoea and bowel symptoms) or totally for the left items. One year after RT, several scores (role and emotional function, constipation) were improved over their baselines, while HTR and sexual function further worsened. Pain, diarrhoea and bowel symptoms remained partially recovered, compared to the baselines. Conclusion Definitive radiotherapy of prostate cancer caused a decline of quality of life with a maximum at the RT end. The majority of symptoms and functions recovered three months after RT, which extended to one year after RT. Several items were even improved over their baselines while two items of sexual function remained worsened. M. Miszczyk 1 , M. Szo ł tysik 1 , M. Hasterok 1 , B. Goc 2 , D. Gräupner 2 , P. Rajwa 3,4 , K. Ras ł awski 2 , I. Jab ł o ń ska 1 , Ł . Magrowski 1 , O. Masri 1 , W. Majewski 1 1 Maria Sklodowska-Curie National Research Institute of Oncology, IIIrd Radiotherapy and Chemotherapy Department, Gliwice, Poland; 2 Maria Sklodowska-Curie National Research Institute of Oncology, Radiotherapy Department, Gliwice, Poland; 3 Comprehensive Cancer Center, Vienna General Hospital, Medical University of Vienna, Department of Urology, Vienna, Austria; 4 Medical University of Silesia, Department of Urology, Zabrze, Poland Purpose or Objective While prostate cancer treatment is increasingly effective its toxicities remain a great concern. In this study, we report on the adverse events (AE) of post-prostatectomy irradiation based on our institutional experience, review the reproducibility of organs-at-risk (OAR) contouring, and finally investigate the association of various dose-volume parameters with treatment sequelae. Materials and Methods We included 167 consecutive patients who had received post-prostatectomy radiotherapy (either adjuvant or salvage) to the prostatic bed with or without pelvic node irradiation. The medical history was reviewed for AE, which were scored according to the CTCAE v.5.0 AE reporting guidelines. The rectum and bladder organs-at-risk were contoured anew, based on the treatment planning computed tomography, following RTOG/NRG Guidelines. The volumes were then compared with the original contours and analyzed based on dose-volume histogram (DVH) values using ROC curves. Kaplan-Meier curves were used to estimate the cumulative rate of toxicity at given time-points (3 months and 5 years). Results The median patients’ age was 63.2 (IQR 58.8 – 67.5), and the median follow-up was 51 months (IQR 22.4-97.1). Grade 2 or higher urinary tract toxicity occurred in 13.3% and 28.2% of the patients at 3 months and 5-years, respectively. A total of 17 (10.2%) patients experienced grade 3 or higher toxicity within the follow-up, most commonly (8.4%) associated with urinary tract obstruction requiring surgical intervention. Grade 2 or higher rectal toxicity occurred in 7.2% and 13.9% of the patients at 3 months and at 5 years. Grade 3 or higher rectal toxicity was much less frequent; reported in 2.4% of patients. There was a trend towards a lower volume of the new rectal contours, as compared to the originally delineated organ, which was found in a majority of the patients (74.9%). The new contours were smaller by a median of 16.5% (IQR 8-28.5). The bladder contours were comparable in approximately 50.9% of patients, and in the majority (83.5%) of the remaining patients, the difference compared to the initial OAR volume was low (<10%). Table 1 presents the association between consecutive dose-volume parameters and grade II or higher rectal and urinary AEs. The presented values, however, did not reach statistical significance. Table 1. AUC values in ROC analysis of selected DVH parameters for the occurrence of grade II or higher GI or GU toxicity. Vx represents the volume (%) of OAR receiving a dose of at least x Gy. PO-1398 Early and late treatment toxicity of post-prostatectomy irradiation