Jorge clinical study: 10-year outcomes of risk-adapted radiotherapy defined by multiparametric MRI for prostate cancer

Abstract

Purpose: To analyze the 10-year biochemical relapse-free survival (BRFS), locoregional relapse-free survival (LRFS), metastasis-free survival (MFS), and overall survival (OS) in patients diagnosed with localized prostate adenocarcinoma treated with radiotherapy (RT) ± androgen deprivation therapy (ADT), according to the risk groups based on multiparametric magnetic resonance imaging (mpMRI) instead of digital rectal exam (DRE).

Methods: We retrospectively evaluated 140 consecutive patients diagnosed with localized prostate adenocarcinoma, stratified into different risk groups-low (LR), intermediate (IR), and high (HR) by mpMRI results.

Results: After a median follow-up of 104 months, in LR group (n = 15), 10-year BRFS was 86.7%, 10-year LRFS was 86.7%, 10-year MFS was 93.3%, and 10-year OS was 100%. In IR group (n = 80), 10-year BRFS was 80.5%, 10-year LRFS was 86.1%, 10-year MFS was 92.6%, and 10-year OS was 76%. In HR group (n = 45), 10-year BRFS was 72.8%, 10-year LRFS was 78.7%, 10-year MFS was 82.1%, and 10-year OS was 77% (2 deaths from prostate cancer). According to mpMRI results, 36 (25.7%) patients change the risk group and 125 (89.28%) patients change the TNM stage. There was a trend for higher metastatic relapse in patients who switched from IR to HR (due to mpMRI) versus the patients who remained in the IR (20%, vs. 1.81% p = 0.059). Multivariate analysis showed that locoregional relapse was strongly associated with distant relapse (OR = 9.28; 95%CI: 2.60-33.31). There were no cases of acute grade 3 toxicity. Late grade 3 genitourinary, gastrointestinal, and sexual toxicity were 2.8%, 0.7%, and 1.2%, respectively.

Conclusion: This is the first study with a 10-year median follow-up of patients diagnosed with localized prostate cancer treated with radiotherapy according to the risk groups established by mpMRI. Our findings show that mpMRI is a key tool to diagnose and establish risk groups in these patients, to optimize their treatment.

Keywords: Androgen deprivation therapy and risk-adapted radiotherapy; Multiparametric magnetic resonance imaging; Prostate cancer; Radiotherapy.