ESTRO 2022 - Abstract Book

S1209

Abstract book

ESTRO 2022

Median follow-up was 20 months. Fourteen patients (42.4%) were alive at last visit. Estimated median OS and PFS were 27.5 months (range, 14.6-40.4 months) and 19.4 months (range, 7.7-31 months), respectively. When we stratified patients by changing or keeping same systemic treatment there was no significant difference between two groups for OS (p=0.381) or PFS (p= 0.201). 1-year OS, PFS and local control (LC) rates were 69%, 38% and 82%, respectively. Clinical or radiological progression was observed in 8 irradiated lesions at first year. There was no grade 3 or more acute or late toxicity in the study cohort. Conclusion By providing excellent local control and low toxicity profile, SBRT is an effective treatment in oligometastatic RCC patients. The clinical outcomes seems similar for patients who continues to the same systemic chemotherapeutic or immunotherapy agent after local treatment of progressed lesion.

PO-1426 IMRT of the prostate following focal treatment: Analysis of Toxicity.

A. Valcárcel Díaz 1

1 Puerta de Hierro University Hospital, Radiation Oncology, Madrid, Spain

Purpose or Objective Cryotherapy (CRYO), irreversible electroporation (IRE), or high-intensity focused ultrasound (HIFU), are different treatment options for early-stage adenocarcinoma of the prostate. Failures following this procedure are not infrequently and little data exists regarding salvage radiotherapy. We summarize our experience. Materials and Methods All consecutive ten cases of salvage radiotherapy following cryoablation, IRE or HIFU failure for cancer prostate from 2011 to 2021 were analyzed.Patients were treated with IMRT and received a mean dose of 72.2 Gy (range, 70-76 Gy) to the prostate and seminal vesicles alone. PSA failure was defined by Phoenix consensus definition. Acute and late GI and GU toxicity were graded according to the CTCAE v5 scale. Results Patients characteristics are shown in table 1. Mean pre-focal treatment PSA was 9.03 ng/ml (4.7-17). Mean PSA prior to irradiation was 10.61 ng/ml (2.2-26.4). Median interval to RT was 25.95 months. Median follow up was 30.63 months. Biochemical control was achieved in 8 of the 10 patients and one developed nodal relapse. All of them are alive at last follow up. Median time to highest GU and GI toxicity was 4,36 and 11.5 months respectively. The acute and highest late toxicity is summarized in table2. Three patients experienced late grade 3 rectal bleeding needing Argon laser treatment (previous diabetes and hypertension in two of them). Only one patient who did not have erectile dysfunction previously, developed it after radiation therapy.

Table 1: Patients characteristics.

Table 2: Acute and highest late toxicity.