ESTRO 2021 Abstract Book

S1104

ESTRO 2021

genitourinary (GU) toxicities were evaluated contextually. QoL of enrolled patients was assessed by IPSS, EORTC QLQ-C30, EORTC QLQ-PR25, and sexual activity by IIEF-5. Data on acute and late GI and GU toxicities were collected according to RTOG/EORTC grading system. Results Patients were treated with a CIRT boost of 16.6 Gy [RBE] in 4 fractions followed by whole-pelvis IMRT of 50 Gy in 25 fractions. From 10/2017 to 02/2021, 24 patients were enrolled in the study and 16 completed the whole RT course. All patients underwent concomitant long-term hormone therapy. Data of 15 patients were available for the preliminary analysis. Immediately after CIRT no patients experienced GU/ GI toxicity. At one and 3 months from the RT completion (CIRT followed by IMRT) no GI or GU toxicities greater than grade (G) 2 were observed. In details, considering acute GU toxicity, 8 patients have not reported any toxicity. Concerning GI 5 patients presented G1 acute toxicity and 2 of them G2. Longer follow up (12 months) was available for 7 patients, with one patient presenting GU toxicity classified as G1 and 1 patient presenting GU toxicity reported as G2. At the time of the writing all the patients have a biochemical control of disease. Conclusion At the current state, the mixed treatment schedule proposed by our study shows an optimal toxicity profile for both acute and chronic toxicity at one year from treatment. Such data instills confidence in the continuation of this mixed approach, whose long-term efficacy together with efficacy (in terms of biochemical control of disease) will be the object of additional analyses. PO-1345 Symptoms affecting Emotional, Systemic and Social Domains 2 years after RT for prostate cancer E. Garibaldi 1 , A. Faiella 2 , E. Villa 3 , A. Magli 4 , D. Cante 5 , B. Avuzzi 6 , J.M. Waskiewicz 7 , L. Ferella 8 , B. Noris Chiorda 6 , G. Girelli 9 , A. Pastorino 1 , C. Piva 5 , M. Gatti 10 , P. Ferrari 11 , A. Maggio 12 , E. Olivetta 13 , G. Sanguineti 2 , V. Vavassori 14 , F. Munoz 8 , T. Rancati 15 , F. Badenchini 15 , A. Bresolin 16 , R. Valdagni 17 , N. Di Muzio 18 , C. Fiorino 16 , C. Cozzarini 19 1 A.O. SS. Antonio e Biagio, Radiotherapy, Alessandria, Italy; 2 IRCCS Istituto Nazionale dei Tumori “Regina Elena", Radiotherapy, Rome, Italy; 3 Cliniche Gavazzeni Humanitas, Radiotherapy, Bergami, Italy; 4 Azienda Ospedaliero Universitaria S. Maria della Misericordia, Radiotherapy, Udine, Italy; 5 Ospedale di Ivrea, Radiotherapy, Ivrea, Italy; 6 Fondazione IRCCS Istituto Nazionale dei Tumori, Radiotherapy, Milan, Italy; 7 Azienda Sanitaria dell’Alto Adige, Radiotherapy, Bolzano, Italy; 8 Ospedale Regionale Parini-AUSL Valle d’Aosta, Radiotherapy, Aosta, Italy; 9 Ospedale degli Infermi, Radiotherapy, Biella, Italy; 10 IRCC Candiolo, Radiotherapy, Candiolo, Italy; 11 Azienda Sanitaria dell’Alto Adige, Medical Physics, Bolzano, Italy; 12 IRCC Candiolo, Medical Physics, Candiolo, Italy; 13 A.O. SS. Antonio e Biagio, Radiotherapy, Aosta, Italy; 14 Cliniche Gavazzeni Humanitas, Radiotherapy, Bergamo, Italy; 15 Fondazione IRCCS Istituto Nazionale dei Tumori, Prostate Program, Radiotherapy, Milan, Italy; 16 San Raffaele Scientific Institute, Medical Physics, Milan, Italy; 17 Fondazione IRCCS Istituto Nazionale dei Tumori, Prostate Program - Università degli Studi Milano, Radiotherapy, Milan, Italy; 18 San Raffaele Scientific Institute - Università Vita Salute San Raffaele, Radiotherapy, Milan, Italy; 19 San Raffaele Scientific Institute, Radiotherapy, Milan, Italy Purpose or Objective To evaluate the effect of both baseline level and radiation-induced worsening of intestinal and urinary symptoms on 2-year deterioration of Emotional, Systemic and Social Domains. Materials and Methods An observational registered study aimed at creating predictive models of RT-induced toxicities in patients receiving WPRT as part of their treatment, and assessing their possible subjective impact, was activated in 2014. Thus far, 375 men treated with radical (RAD, n=137), adjuvant (ADV, n=86) and salvage, (SALV n=152) radiotherapy have filled-in, at baseline and two years after RT end, the IBDQ (Inflammatory Bowel Disease Questionnaire) evaluating the RT-induced bowel symptoms and their impact on Emotional, Systemic and Social patient Domains. The median 2-Gy equivalent dose (EQD2, α/β 3 Gy) to the PTV prostate was 80.03 Gy, to the PTV prostatic bed 70.39 and 73.14 Gy in ADV and SALV cohort, respectively, to the lymph-nodal PTV 51.14 Gy. Androgen deprivation therapy (ADT) was given to 218 (58%) patients for a median of 24.3 months. Assuming that the three Domains may have been affected by several urinary and intestinal symptoms, the possible role of both baseline level and the 2-year worsening (D) of urinary symptoms and incontinence as measured by IPSS 1-8 and ICIQSF 3-4-5 items, respectively, and of the ten IBDQ bowel symptoms as measured by the IBDQ questionnaire, was evaluated. In addition, the possible detrimental impact of several clinico-dosimetric variables, including RT intent and doses, androgen deprivation therapy and patient personality as measured by the EPQR questionnaire, was considered. Since the worsening of the three domains was mild overall (≤0.80 on a 1-7 scale with lower scores indicating worse symptoms), the 10 th percentile of the worst D at 2 years relative to baseline was set as end-point for univariable analyses (UVA). Variables with a p-value <0.05 at UVA were entered into a multivariable regression logistic model (MVA). Results The results of the MVA are shown in the Table. The 2-year impairment of the Emotional domain was mainly caused by the worsening of intestinal symptoms, with no role for urinary disturbance. Adjuvant RT independently affected the Social domain, differently from both RAD and SALV, while urinary intermittency was the sole urinary symptom whose 2-year worsening independently impaired both Systemic and Social domains.