Journal of contemporary brachytherapy · 2026
Impact of needle number on dosimetric parameters in high-dose-rate prostate brachytherapy: A single-institution retrospective study.
СтатьяНазвание и аннотация: Перевод пока не подготовлен
Обработка статьи · этапы, ошибки и управление
Загрузка состояния…
Ошибки и ограничения
История · было → стало
Состояние обновляется каждые 5 секунд, пока блок открыт. Процент показывается только там, где известен объём работы. Пауза останавливает продолжение этапа; текущий запрос к источнику может завершиться.
Yankova Yana, Nedev Kamen, Nedev Nikolay, Stoyanov Desislav, Enikov Boris, Angelov Tsvetomir, Markov Milen
Аннотация
PURPOSE: To evaluate how the number of implanted needles per fraction influences target coverage, dose heterogeneity, and organ at risk (OAR) exposure in high-dose-rate (HDR) prostate brachytherapy.
MATERIAL AND METHODS: Retrospective planning system data from 2016 to 2025 were analyzed the level of individual treatment fractions (1,850 fractions from 1,008 patients). Fractions were stratified by needle number into three groups: ≤ 14 needles (n = 202, 10.9%), 15-18 needles (n = 761, 41.1%), and 19-24 needles (n = 887, 47.9%). DVH (dose-volume histogram) doses were reported as percentage of prescription dose (%Rx). Kruskal-Wallis test was used between-group comparisons, with Dunn post-hoc correction (Bonferroni), while associations were assessed with Spearman's ρ. Multivariable mixed-effects models with patient ID as random effect accounted for within-patient clustering.
RESULTS: Prostate volume differed significantly across needle groups (H = 619.66, p < 0.001), with more needles used in larger glands. Target coverage remained stable across all groups (V100% ≈ 95.3-95.4%, D90% ≈ 107.6-107.9% Rx). High-dose indicators decreased progressively: Prostate V200% from 14.33% to 12.41%, and prostate D1% from 616% to 497% Rx. Urethra D1% decreased from 129.5% to 124.6% Rx (ρ = -0.22, p < 0.001), whereas rectum D30% increased modestly from 60.3% to 63.0% Rx (ρ = 0.18, p < 0.001). All pairwise comparisons were significant (all p < 0.001), except rectum D30%, between the ≤ 14 and 15-18 needle groups (p = 0.52). The needle number remained a significant independent predictor of all key dosimetric outcomes after adjustment for prostate volume.
CONCLUSIONS: A higher needle number was associated with reduced prostate hot spots and lower urethral peak dose while preserving target coverage. These findings support volume-adapted implant catheter density as a practical strategy to improve dose homogeneity in routine HDR prostate brachytherapy. Prostate volume is a major confounder, and should be considered in outcome-linked analyses and institutional benchmarking.
MATERIAL AND METHODS: Retrospective planning system data from 2016 to 2025 were analyzed the level of individual treatment fractions (1,850 fractions from 1,008 patients). Fractions were stratified by needle number into three groups: ≤ 14 needles (n = 202, 10.9%), 15-18 needles (n = 761, 41.1%), and 19-24 needles (n = 887, 47.9%). DVH (dose-volume histogram) doses were reported as percentage of prescription dose (%Rx). Kruskal-Wallis test was used between-group comparisons, with Dunn post-hoc correction (Bonferroni), while associations were assessed with Spearman's ρ. Multivariable mixed-effects models with patient ID as random effect accounted for within-patient clustering.
RESULTS: Prostate volume differed significantly across needle groups (H = 619.66, p < 0.001), with more needles used in larger glands. Target coverage remained stable across all groups (V100% ≈ 95.3-95.4%, D90% ≈ 107.6-107.9% Rx). High-dose indicators decreased progressively: Prostate V200% from 14.33% to 12.41%, and prostate D1% from 616% to 497% Rx. Urethra D1% decreased from 129.5% to 124.6% Rx (ρ = -0.22, p < 0.001), whereas rectum D30% increased modestly from 60.3% to 63.0% Rx (ρ = 0.18, p < 0.001). All pairwise comparisons were significant (all p < 0.001), except rectum D30%, between the ≤ 14 and 15-18 needle groups (p = 0.52). The needle number remained a significant independent predictor of all key dosimetric outcomes after adjustment for prostate volume.
CONCLUSIONS: A higher needle number was associated with reduced prostate hot spots and lower urethral peak dose while preserving target coverage. These findings support volume-adapted implant catheter density as a practical strategy to improve dose homogeneity in routine HDR prostate brachytherapy. Prostate volume is a major confounder, and should be considered in outcome-linked analyses and institutional benchmarking.