# Quality of Life in Japanese Men Treated with Intensity Modulated Radiotherapy for Localized Prostate Cancer: Three-Year Longitudinal Evaluation Using Patient-Reported Outcomes of the Expanded Prostate Index Composite (EPIC)

**Authors:** Norio Mitsuhashi, Atsushi Motegi, Hajime Ikeda, Yoshitaka Nemoto, Daichi Tominaga, Fumiya Shiina, Yukiko Muto, Keiko Fukaya, Atsushi Yamauchi, Shinichi Yoshii

PMC · DOI: 10.3390/jcm15051780 · 2026-02-26

## TL;DR

This study tracks the quality of life of Japanese men treated with IMRT for prostate cancer over three years, showing recovery in urinary and bowel functions but persistent sexual issues.

## Contribution

The study provides a three-year longitudinal evaluation of QOL using EPIC in prostate cancer patients treated with IMRT, with or without ADT.

## Key findings

- Urinary and bowel scores decreased shortly after IMRT but returned to baseline within three months.
- Sexual scores remained low throughout the study period, with minimal recovery observed.
- Hormonal scores improved significantly two to three years after IMRT initiation.

## Abstract

Background/Objectives: We assessed the changes in the quality of life (QOL) of patients with localized prostate cancer who were treated with IMRT, either with or without Androgen Deprivation Therapy (ADT), using the Expanded Prostate Index Composite (EPIC). Methods: Changes in EPIC summary and subdomain scores were evaluated using longitudinal analyses at eight time points up to three years after IMRT. Results: The urinary score and four subdomain scores decreased significantly four weeks after the start of IMRT but returned to the baseline level three months after IMRT. This pattern of change remained consistent, regardless of whether ADT was administered or not. The longitudinal changes in bowel score were the same as those in the urinary score. The recovery of the bowel bother subdomain score was rapid, occurring as early as one month after IMRT. Regardless of whether ADT was administered, there was no difference in longitudinal changes in bowel scores. The sexual score remained consistently low throughout the survey period, ranging from 33 to 35. The baseline score for the sexual bother subdomain was 94.44, but the score for the sexual function subdomain was extremely low at 8.24. The hormonal score at the start of IMRT was 87.37 but increased significantly at two and three years after IMRT. The hormonal bother subdomain score decreased significantly six months after IMRT initiation but subsequently increased, becoming significantly higher three years after IMRT. Conclusions: IMRT has made it possible to minimize deterioration in the quality of life of patients with localized prostate cancer by reducing adverse events.

## Linked entities

- **Diseases:** prostate cancer (MONDO:0005159)

## Full-text entities

- **Diseases:** Prostate Cancer (MESH:D011471)
- **Species:** Homo sapiens (human, species) [taxon 9606]

## Figures

7 figures with captions in the complete paper: https://tomesphere.com/paper/PMC12986111/full.md

---
Source: https://tomesphere.com/paper/PMC12986111