TY  - JOUR
A1  - Tamihardja, Jörg
A1  - Lawrenz, Ingulf
A1  - Lutyj, Paul
A1  - Weick, Stefan
A1  - Guckenberger, Matthias
A1  - Polat, Bülent
A1  - Flentje, Michael
T1  - Propensity score-matched analysis comparing dose-escalated intensity-modulated radiation therapy versus external beam radiation therapy plus high-dose-rate brachytherapy for localized prostate cancer
JF  - Strahlentherapie und Onkologie
N2  - Purpose
Dose-escalated external beam radiation therapy (EBRT) and EBRT + high-dose-rate brachytherapy (HDR-BT) boost are guideline-recommended treatment options for localized prostate cancer. The purpose of this study was to compare long-term outcome and toxicity of dose-escalated EBRT versus EBRT + HDR-BT boost.

Methods
From 2002 to 2019, 744 consecutive patients received either EBRT or EBRT + HDR-BT boost, of whom 516 patients were propensity score matched. Median follow-up was 95.3 months. Cone beam CT image-guided EBRT consisted of 33 fractions of intensity-modulated radiation therapy with simultaneous integrated boost up to 76.23 Gy (D\(_{Mean}\)). Combined treatment was delivered as 46 Gy (D\(_{Mean}\)) EBRT, followed by two fractions HDR-BT boost with 9 Gy (D\(_{90\%}\)). Propensity score matching was applied before analysis of the primary endpoint, estimated 10-year biochemical relapse-free survival (bRFS), and the secondary endpoints metastasis-free survival (MFS) and overall survival (OS). Prognostic parameters were analyzed by Cox proportional hazard modelling. Genitourinary (GU)/gastrointestinal (GI) toxicity evaluation used the Common Toxicity Criteria for Adverse Events (v5.0).

Results
The estimated 10-year bRFS was 82.0% vs. 76.4% (p = 0.075) for EBRT alone versus combined treatment, respectively. The estimated 10-year MFS was 82.9% vs. 87.0% (p = 0.195) and the 10-year OS was 65.7% vs. 68.9% (p = 0.303), respectively. Cumulative 5‑year late GU ≥ grade 2 toxicities were seen in 23.6% vs. 19.2% (p = 0.086) and 5‑year late GI ≥ grade 2 toxicities in 11.1% vs. 5.0% of the patients (p = 0.002); cumulative 5‑year late grade 3 GU toxicity occurred in 4.2% vs. 3.6% (p = 0.401) and GI toxicity in 1.0% vs. 0.3% (p = 0.249), respectively.

Conclusion
Both treatment groups showed excellent long-term outcomes with low rates of severe toxicity.
KW  - long-term outcome
KW  - dose escalation
KW  - high-dose-rate brachytherapy boost
KW  - propensity score matching
KW  - toxicity
Y1  - 2022
U6  - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:bvb:20-opus-325055
VL  - 198
IS  - 8
ER  -