S1224
Clinical - Urology
ESTRO 2026
Keywords: PSMA-PET, Prostate canc, Clinical practice pattern
assessment (n=20), risk calculators (n=12), or genetic classifiers (n=2). For PSMA-PET positive lymph nodes, 92% of centers perform dose escalation, most commonly using MHF to 71 Gy (EQD2) (43%), conventional fractionation to 68 Gy (43%), or SBRT to 79 Gy (EQD2) (14%). Conclusion: This international survey demonstrates strong commitment to the Co-IMPACT consortium and reveals high PSMA-PET utilization with substantial in- house availability. While moderate hypofractionation dominates current practice, considerable heterogeneity exists in treatment approaches, particularly regarding elective nodal irradiation and dose escalation strategies. These findings underscore the need for the Co-IMPACT registry to generate robust evidence guiding optimal integration of PSMA- PET information into radiotherapy decision-making for prostate cancer.
Digital Poster 2323
ROLE OF RADIOTHERAPY IN NODE METASTASES FROM PROSTATE CANCER: ANALYSIS OF A LARGE SINGLE-INSTITUTION COHORT Laura Giannini 1 , Andrei Fodor 1 , Monica Maria Vincenzi 2 , Chiara Lucrezia Deantoni 1 , Miriam Torrisi 1 , Claudio Fiorino 2 , Roberta Tummineri 1 , Sara Broggi 2 , Carmen Gigliotti 2 , Antonella Del Vecchio 2 , Nadia Di Muzio 1,3 1 Radiation Oncology, IRCCS Ospedale San Raffaele, Milano, Italy. 2 Medical Physics, IRCCS Ospedale San Raffaele, Milano, Italy. 3 Radiation Oncology, Università Vita Salute San Raffaele, Milano, Italy Purpose/Objective: Prostate cancer (PCa) commonly metastasizes to lymph nodes,which are often the only site of disease detected by PET.The optimal treatment strategy remains under investigation and Metastasis Directed Therapy may represent a valuable option.This study aims to analyze local, regional and distant recurrence- free survival, as well as toxicity, in a large cohort of patients (pts) with node metastases from Pca treated with stereotactic body radiotherapy (SBRT) or elective nodal radiotherapy (ENRT) with Simultaneous Integrated Boost to the PET-positive nodes. Material/Methods: Between 02/2005 and 06/2024,317 treatments were delivered to 912 PET-positive nodes located in the pelvic,para-aortic, or supradiaphragmatic regions.Node treatments performed with ENRT were analyzed collectively,while node treatments performed with SBRT were analyzed individually, even when administered within the same treatment period.The median age at treatment was 70 years (50- 87).Dosimetric data are reported in Table 1.BED was calculated using an α / β ratio of 1.5 for the prostate.ENRT treatments were planned using Helical IMRT or VMAT. SBRT was delivered using a Robotic LINAC in 69 cases and Helical IMRT for 21 cases.Survival curves were estimated using Kaplan- Meier method.Prognostic factors for survival were assessed using a univariate Cox model.Toxicity was assessed according to the Common Terminology Criteria for Adverse Events version 5.0.VariablesENRT(n=227)SBRT(n=90)Nodal Chain Fractions(median)28(range 15-30)/Nodal Chain BED (Gy, median)115.7 Gy(range 106.9-160 Gy)/BTV/node Fraction(median)28(range 15-37)5(range 3-30)BTV/node BED(Gy, median)162.8 Gy(range 116.7- 205.3 Gy)209.2 Gy(range 108.3-378 Gy)Table 1
Made with FlippingBook - Share PDF online