Coverage of the external prostatic region by the hybrid method compared with the conventional method of prostate low‐dose‐rate brachytherapy: A randomized controlled study. (11th August 2020)

• Record Type: Journal Article
• Authors: Tanaka, Nobumichi; Asakawa, Isao; Nakai, Yasushi; Miyake, Makito; Anai, Satoshi; Yamaki, Kaori; Fujii, Tomomi; Hasegawa, Masatoshi; Fujimoto, Kiyohide
• Is Part Of: International journal of urology. Volume 27:Number 11(2020)
• Page Start: 1013
• Page End: 1017
• Publication Date: 2020-08-11
• Subjects: brachytherapy -- dose‐volume histogram -- loose seeds -- prostate cancer -- stranded seeds; Urology -- Periodicals; Genitourinary organs -- Periodicals; Urologic Diseases -- Periodicals; 616.6005
• DOI: 10.1111/iju.14349
• Languages: English
• ISSNs: 0919-8172

Abstract

Abstract : Objectives: To compare the dose evaluation parameters between conventional (using loose seed alone) and hybrid (using loose seeds in combination with stranded seeds) low‐dose rate brachytherapy for prostate cancer. Methods: Between 2014 and July 2016, a total of 219 patients who underwent low‐dose rate brachytherapy were enrolled in a randomized controlled trial (trial number: UMIN 000012780). Patients were randomized and allocated to two groups (conventional method vs hybrid method). Post‐dosimetric parameters (%D90, minimal percentage of the dose received by 90% of the prostate gland; V100, percentage of the prostate volume receiving 100% of the prescribed minimal peripheral dose; V150, percentage of the prostate volume receiving 150% of the prescribed minimal peripheral dose; %UD30, minimal percentage of the dose received by 30% of the urethra; R100, rectal volume [mL] receiving 100% of the prescribed dose) calculated at 1 month after seed implantation by computed tomography scan were compared between the two groups, as well as the post‐dosimetric parameters using the planning target volume of the prostate + 5‐mm margin. Results: Regarding dose evaluation parameters, the prostate dose (%D90, V100, V150) and the urethral dose (%UD30) were not significantly different between the two groups, whereas V100 (+5‐mm margin) and %D90 (+5‐mm margin) were significantly higher in the hybrid method group compared with the conventional method group ( P < 0.001). Conclusion: The present randomized study shows that the hybrid method of low‐dose rate brachytherapy can achieve a higher coverage of the periprostatic region compared with the conventional method while maintaining an acceptable level of urethral and rectal doses.