Prostate-specific Antigen Levels Following Brachytherapy Impact Late Biochemical Recurrence in Japanese Patients With Localized Prostate Cancer

• Published in: In vivo (Athens) 2023-03, Vol.37 (2), p.738-746
• Main Authors: Ueno, Yoshiteru, Fukumori, Tomoharu, Kusuhara, Yoshito, Fukawa, Tomoya, Tsuda, Megumi, Daizumoto, Kei, Sasaki, Yutaro, Tomida, Ryotaro, Yamamoto, Yasuyo, Yamaguchi, Kunihisa, Tonoiso, Chisato, Kubo, Akiko, Kawanaka, Takashi, Furutani, Shunsuke, Ikushima, Hitoshi, Takahashi, Masayuki, Kanayama, Hiro-Omi
• Format: Article
• Language: English
• Subjects: Brachytherapy; Cohort Studies; East Asian People; Humans; Male; Prostate-Specific Antigen; Prostatic Neoplasms - radiotherapy
• ISSN: 0258-851X; 1791-7549
• DOI: 10.21873/invivo.13136

Evaluation of long-term outcomes is essential for the successful treatment of localized prostate cancer; however, the risk of late recurrence following brachytherapy is still not clear. This study aimed to evaluate the long-term outcomes of low-dose-rate brachytherapy (LDR-BT) for localized prostate cancer in Japanese patients and identify factors associated with late recurrence after treatment. This single-center, cohort study included patients who underwent LDR-BT at the Tokushima University Hospital in Japan between July 2004 and January 2015; 418 patients, who were followed-up at least 7 years after LDR-BT, were included in the study. Biochemical progression free survival (bPFS) was defined according to the Phoenix definition (nadir PSA+2 ng/ml) and bPFS and cancer specific survival (CSS) were calculated using Kaplan-Meier survival curves. Univariate and multivariate analyses were performed using Cox proportional hazard regression models. Approximately half of the patients with PSA >0.5 ng/ml at 5 years after LDR-BT had a recurrence within the next 2 years. However, only 1.4% of the patients with a PSA ≤0.2 ng/ml at 5 years post-treatment showed tumor recurrence, including those at high risk of treatment failure according to the D'Amico classification. In multivariate analysis, PSA level at 5 years post-treatment was the only predictor of late recurrence after 7 years of treatment. PSA levels at 5 years post-treatment were associated with long-term recurrence of localized prostate cancer, which can help alleviate patient anxiety concerning prostate cancer recurrence if PSA levels remain low at 5 years after LDR-BT.