Ultrahypofractionation in localized prostate cancer: the first experience of using proton radiation therapy in one center. Data for the first two years

Abstract

Aim:to analyze our experience of using the ultra-hypofractionated proton radiation therapy for patients with localized prostate cancer (PC) with an assessment of late toxicity according to data for the first two years of using this therapy. Patients and Methods: 73 patients with PC were treated using intensity modulated proton therapy (IMPT) in ultra-hypofractionation mode from February 2019 to February 2021. We studied data on late toxicity of radiotherapy and biochemical recurrence-free survival (BRFS) in 56 patients, 17 were excluded from the follow-up. Data on the level of prostate-specific antigen (PSA) in patients and late toxicity of prostate cancer radiotherapy (PCRT) were collected based on the results of a telephone survey using a standardized questionnaire and analyzed after 22 (2; 46) months. Results: late toxicity according to the criteria of NCI CTCAEv.5.0 was from the gastrointestinal (GI) tract: grade 1 phenomena developed in 10 (17.9%) patients, grade 2 — in 3 (5.3%). None of the patients reported grade 3 (or higher) chronic GI toxicity. From the genitourinary system: grade 1 toxicity was observed in 8 (14.3%) patients, grade 2 — in 6 (10.7%), none of the patients reported grade 3 (or higher) toxicity. The erectile dysfunction was also registered in 8 (14.3%) patients. Two (2.7%) patients died from causes unrelated to PC. No progression was observed when analyzing the data of the biochemical and clinical studies. There have been no reported fatal outcomes related to PC. Conclusion: in patients who received IMPT in the ultra-hypofractionated mode, the level of late toxicity from the genitourinary system and gastrointestinal tract was similar to the data of the only foreign literature study on the use of ultra-hypofractionated proton radiation therapy. The level of biochemical control we obtained was similar to other methods of radiation therapy with similar modes of dose adjustment. KEYWORDS: prostate cancer, radiation therapy, proton therapy, toxicity, survival, ultra-hypofractionated mode. FOR CITATION: Kataev N.A., Vorobyov N.A., Mikhailov A.V. et al. Ultrahypofractionation in localized prostate cancer: the first experience of using proton radiation therapy in one center. Data for the first two years.. Russian Medical Inquiry. 2023;7(4):196–201 (in Russ.). DOI: 10.32364/2587-6821-2023-7-4-196-201.