Comparison of EBRT and I-125 seed brachytherapy concerning outcome in intermediate-risk prostate cancer

Abstract

Purpose This study’s objective was the comparison of external beam radiotherapy (EBRT) and I‑125 seed brachytherapy regarding clinical outcome and development of side effects. Patients and methods In all, 462 localized intermediate-risk prostate cancer patients treated between 2000 and 2019 at our department using either I‑125 seed brachytherapy or EBRT with a dose of 74 or 78 Gy were included: 297 patients were treated with EBRT and 165 with seeds. Biochemical no evidence of disease (bNED) rates according to Phoenix definition as well as late gastrointestinal and urogenital side effects (EORTC/RTOG) were assessed. Results Patients were followed up yearly with a median follow-up of 54 (3–192) months. Observed bNED rates for 74 Gy, 78 Gy and seeds were 87, 92, and 88% after 5 years and 71, 85, and 76% after 9 years, respectively. No significant differences were found comparing seeds with 74 Gy (p = 0.81) and 78 Gy (p = 0.19), as well as between 74 and 78 Gy (p = 0.32). Concerning gastrointestinal side effects, EBRT showed significantly higher rates of RTOG grade ≥ 2 toxicity compared to seeds, but at no point of the follow-up more than 10% of all patients. However, genitourinary side effects were significantly more prevalent in patients treated with seeds, with 33% RTOG grade ≥ 2 toxicity 12 months after treatment. Nevertheless, both types of side effects decreased over time. Conclusion Favorable intermediate-risk prostate cancer patients can be treated either by external beam radiotherapy (74/78 Gy) or permanent interstitial seed brachytherapy.

Brachytherapy on-a-chip: a clinically-relevant approach for radiotherapy testing in 3d biology

“…This effect is commonly exploited in various modalities, has been long known and accounted for in the clinic heuristically, and can be advantageous for sparing of adjacent normal tissue. 2,9,53 Indeed, the source we used in this set of experiments, I125, is classified as a low-dose rate (LDR) BT, requiring in our chip roughly 2 hours to deliver the 8 Gy target to the first row of spheroids. 7,9 By contrast, EBRT delivered using the GammaCell cabinet treated spheroids with 8 Gy in around 2 minutes, a 60-times higher dose rate.…”

Comparison of chronic gastrointestinal and genitourinary toxicities between brachytherapy and external beam radiotherapy for patients with prostate cancer: A systematic review and meta-analysis

“…Previous studies reported a 15 years disease-free survival rate of 80.4% after treatment of men with localized prostate cancer with BT [ 57 , 58 ]. Another studies reported a 5 years and 10 years OS rate of 94% and 84%, respectively, among similar patients [ 59 ].…”