Optimization of clinical target volume delineation for prostate cancer radiotherapy based on prostate bed occurrence patterns in prostate-specific membrane antigen positron emission tomography
10.3760/cma.j.cn112271-20241103-00422
- VernacularTitle:基于前列腺特异性膜抗原PET术床复发规律优化前列腺癌放疗临床靶区的研究
- Author:
Huan ZHANG
1
;
Xin QI
;
Xuhe LIAO
;
Cheng CHEN
;
Jingyun WU
;
Jianhua ZHANG
;
Yan FAN
;
Xianshu GAO
;
Hongzhen LI
Author Information
1. 北京大学第一医院放射治疗科，北京 100032
- Publication Type:Journal Article
- Keywords:
Prostate cancer;
Prostate-specific membrane antigen positron emission tomography (PSMA PET);
Prostate bed recurrence;
Postoperative radiotherapy;
Zoning
- From:
Chinese Journal of Radiological Medicine and Protection
2025;45(10):966-972
- CountryChina
- Language:Chinese
-
Abstract:
Objective:To explore the optimization potential of clinical target volume (CTV) delineation proposed in the guidelines of the Oncology Group (RTOG), the Francophone Group of Urological Radiotherapy (GFRU), and the European Society for Radiotherapy and Oncology (ESTRO) based on prostate bed local occurrence patterns after radical prostatectomy identified using prostate-specific membrane antigen positron emission tomography (PSMA PET).Methods:A retrospective analysis was conducted on patients with local prostate bed recurrence after radical prostatectomy who underwent PSMA PET at the Department of Nuclear Medicine, Peking University First Hospital from September 2021 to February 2024. The central point of each recurrence was marked. A six-zone method was established based on prostate bed anatomy and the characteristics of cross-sectional imaging. Then, the positional relationships (within or outside) were recorded with respect to recurrences and CTV defined by the RTOG, GFRU, and ESTRO (CTV RTOG, CTV GFRU, and CTV ESTRO), followed the analysis of the recurrence rates and distribution characteristics of various zones. Results:A total of 63 patients with prostate bed recurrence after radical prostatectomy were enrolled in this study, including 97 recurrences. The recurrence rates in the six zones were as follows: 10% of zone 1, 22% of zone 2, 29% of zone 3, 2% of zone 4, 12% of zone 5a, 18% of zone 5b, and 7% of zone 6. Among these zones, zones 2 and 3 showed the highest and second-highest recurrence rates, respectively. CTV GFRU and CTV ESTRO completely covered zones 2 and 3, while CTV RTOG covered zone 2 completely and zone 3 partially. Zone 4, characterized by a low recurrence rate, was not covered by CTV GFRU and CTV ESTRO but was entirely covered by CTV RTOG. Zone 5a, with a recurrence rate of 12%, was completely covered by CTV RTOG but was partially covered by CTV GFRU and CTV ESTRO. The range of 1.3 cm in front of the posterior wall of the bladder covered all recurrences in zone 5a. Conclusions:For CTV delineation of the prostate cancer surgical bed, zone 4, the anterior half of the bladder above the pubic symphysis midpoint, should be contracted due to the low recurrence rate in this zone. In contrast, the anterior boundary above the pubic symphysis midpoint should extend to 1.3 cm in front of the posterior wall of the bladder to completely cover the recurrence zones.
