Brachytherapy boost improves survival and decreases risk of developing distant metastases compared to external beam radiotherapy alone in intermediate and high risk group prostate cancer patients

Marcin Miszczyk; Łukasz Magrowski; Tomasz Krzysztofiak; Rafał Stando; Wojciech Majewski; Konrad Stawiski; Oliwia Masri; Jakub Ciepał; Gabriela Depowska; Krystyna Chimiak; Gabriela Bylica; Barbara Czapla; Małgorzata Masri; Franciszek Cichur; Iwona Jabłońska; Marta Gmerek; Zuzanna Nowicka; Piotr Wojcieszek; Jacek Sadowski; Rafał Suwiński; Paweł Rajwa; Gregor Goldner; Matthias Moll

doi:10.1016/j.radonc.2023.109632

Brachytherapy boost improves survival and decreases risk of developing distant metastases compared to external beam radiotherapy alone in intermediate and high risk group prostate cancer patients

Radiother Oncol. 2023 Jun:183:109632. doi: 10.1016/j.radonc.2023.109632. Epub 2023 Mar 23.

Authors

Marcin Miszczyk¹, Łukasz Magrowski², Tomasz Krzysztofiak³, Rafał Stando⁴, Wojciech Majewski⁵, Konrad Stawiski⁶, Oliwia Masri², Jakub Ciepał², Gabriela Depowska², Krystyna Chimiak², Gabriela Bylica², Barbara Czapla², Małgorzata Masri², Franciszek Cichur², Iwona Jabłońska², Marta Gmerek², Zuzanna Nowicka⁶, Piotr Wojcieszek³, Jacek Sadowski⁴, Rafał Suwiński⁷, Paweł Rajwa⁸, Gregor Goldner⁹, Matthias Moll⁹

Affiliations

¹ IIIrd Radiotherapy and Chemotherapy Department, Maria Skłodowska-Curie National Research Institute of Oncology, Wybrzeże Armii Krajowej 15, 44-102 Gliwice, Poland; Department of Radiation Oncology, Comprehensive Cancer Center, Medical University of Vienna, Währinger Gürtel 18-20, 1090 Vienna, Austria. Electronic address: marcin.miszczyk@io.gliwice.pl.
² IIIrd Radiotherapy and Chemotherapy Department, Maria Skłodowska-Curie National Research Institute of Oncology, Wybrzeże Armii Krajowej 15, 44-102 Gliwice, Poland.
³ Brachytherapy Department, Maria Skłodowska-Curie National Research Institute of Oncology Gliwice Branch, Wybrzeże Armii Krajowej 15, 44-102 Gliwice, Poland.
⁴ Department of Radiotherapy, Holy Cross Cancer Center, Stefana Artwińskiego 3, 25-734 Kielce, Poland.
⁵ Radiotherapy Department, Maria Skłodowska-Curie National Research Institute of Oncology, Gliwice Branch, Wybrzeże Armii Krajowej 15, 44-102 Gliwice, Poland.
⁶ Department of Biostatistics and Translational Medicine, Medical University of Łódź, al. Tadeusza Kościuszki 4, 90-419 Łódź, Poland.
⁷ IInd Radiotherapy and Chemotherapy Department, Maria Skłodowska-Curie National Research Institute of Oncology, Wybrzeże Armii Krajowej 15, 44-102 Gliwice, Poland.
⁸ Department of Urology, Comprehensive Cancer Center, Vienna General Hospital, Medical University of Vienna, Währinger Gürtel 18-20, 1090 Vienna, Austria; Department of Urology, Medical University of Silesia, 3-go Maja 13-15, 41-800 Zabrze, Poland.
⁹ Department of Radiation Oncology, Comprehensive Cancer Center, Medical University of Vienna, Währinger Gürtel 18-20, 1090 Vienna, Austria.

PMID: 36963442
DOI: 10.1016/j.radonc.2023.109632

Abstract

Background and purpose: Despite several prospective trials showing a clinical benefit of combining external beam radiotherapy (EBRT) with brachytherapy boost (BTB) for the treatment of intermediate- and high-risk prostate cancer (PCa) patients, none of these trials was designed to test for a survival difference. In this study, we aimed to collect a large multi-institutional database to determine whether BT boost was associated with a statistically significant improvement in survival and a reduction of distant metastases based on real-world data.

Material and methods: We collected the data of patients treated for intermediate- or high-risk PCa with definitive EBRT or BTB, with or without androgen deprivation therapy (ADT), between January 2003 and December 2014 at two tertiary institutions. The statistical endpoints included overall survival (OS), freedom from distant metastases (FFDM), and metastases-free survival (MFS). The impact of treatment modality was assessed using Cox regression models and log-rank testing after one-to-one propensity score matching.

Results: A total of 1641 patients treated with EBRT (n = 1148) or high-dose-rate BTB (n = 493) were analyzed. The median survival and clinical follow-up were 117.8 (IQR 78-143.3) and 60.7 months, respectively. The radiotherapy modality (BTB) remained an independent prognostic factor for OS (HR 0.75; 95% CI 0.63-0.88; p < 0.001), FFDM (HR 0.54; 95% CI 0.4-0.73; p < 0.001), and MFS (HR 0.72; 95% CI 0.61-0.85; p < 0.001). After propensity score matching, the remaining 986 patients were well-balanced in terms of age, maximum PSA, ISUP grade group, and TNM T stage. OS (p < 0.001), FFDM (p = 0.001) and MFS (p < 0.001) were significantly higher in the BTB group.

Conclusions: There is a strong positive association between BTB and OS, FFDM, and MFS in PCa patients treated with definitive RT for intermediate- or high-risk PCa.

Keywords: Brachytherapy boost; High-dose-rate brachytherapy; Prostate cancer; Survival.

MeSH terms

Androgen Antagonists / therapeutic use
Brachytherapy* / adverse effects
Humans
Male
Proportional Hazards Models
Prospective Studies
Prostatic Neoplasms* / pathology
Retrospective Studies

Substances

Androgen Antagonists