Cargando…

Focal low-dose-rate prostate brachytherapy for low- and intermediate-risk prostate cancer

PURPOSE: To prospectively investigate the efficacy and feasibility of focal low-dose-rate (LDR) prostate brachytherapy for low- and intermediate-risk prostate cancer. MATERIAL AND METHODS: Between October 2014 and May 2019, nineteen low- and intermediate-risk prostate cancer patients who presented w...

Descripción completa

Detalles Bibliográficos
Autores principales: Kunogi, Hiroaki, Wakumoto, Yoshiaki, Kawamoto, Terufumi, Oshima, Masaki, Horie, Shigeo, Sasai, Keisuke
Formato: Online Artículo Texto
Lenguaje:English
Publicado: Termedia Publishing House 2020
Materias:
Acceso en línea:https://www.ncbi.nlm.nih.gov/pmc/articles/PMC7787206/
https://www.ncbi.nlm.nih.gov/pubmed/33437303
http://dx.doi.org/10.5114/jcb.2020.101688
_version_ 1783632779403067392
author Kunogi, Hiroaki
Wakumoto, Yoshiaki
Kawamoto, Terufumi
Oshima, Masaki
Horie, Shigeo
Sasai, Keisuke
author_facet Kunogi, Hiroaki
Wakumoto, Yoshiaki
Kawamoto, Terufumi
Oshima, Masaki
Horie, Shigeo
Sasai, Keisuke
author_sort Kunogi, Hiroaki
collection PubMed
description PURPOSE: To prospectively investigate the efficacy and feasibility of focal low-dose-rate (LDR) prostate brachytherapy for low- and intermediate-risk prostate cancer. MATERIAL AND METHODS: Between October 2014 and May 2019, nineteen low- and intermediate-risk prostate cancer patients who presented with abnormality on both diffusion-weighted and T2-weighted magnetic resonance imaging (MRI) underwent focal LDR brachytherapy at our institution. Focal gross tumor volume (F-GTV) was delineated on transrectal ultrasound, based on abnormality seen on fused T2-weighted MRI. F-GTV was expanded by 5 mm, as a safety margin, to create focal clinical target volume (F-CTV). Prescribed dose to F-CTV was 145 Gy. Biochemical recurrence (BCR) was determined using Phoenix criterion (prostate specific antigen nadir + 2 ng/ml). Pre- and post-implant dosimetry data were compared using non-parametric Wilcoxon’s rank sum test. Treatment-related toxicities were evaluated using common terminology criteria for adverse events. RESULTS: Mean F-CTV D(90%) was significantly lower in the post-implant evaluation than in intraoperative planning (p = 0.004). On post-implant dosimetry, the mean D(90%) for F-GTV and mean V(100%) for the entire prostate were 222 Gy and 35%, respectively. Median follow-up time for all patients was 31 months. BCR occurred in one patient after 23 months. Kaplan-Meier 2-year BCR-free rate was 92.9% (95% confidence interval [CI]: 79.4-100%). No patients had grade 1 or greater gastrointestinal toxicity. Three patients who were taking α-blockers to treat benign prostatic hyperplasia (present before brachytherapy), experienced no treatment-related genitourinary toxicities. Two patients suffered from temporary grade 2 urinary frequency. None of the remaining patients experienced grade 2 or higher genitourinary toxicity. CONCLUSIONS: Focal LDR prostate brachytherapy appears acceptable for MRI-based index tumors, with a low cumulative incidence of BCR. Such brachytherapy might offer a feasible minimally invasive therapeutic option for localized prostate cancer.
format Online
Article
Text
id pubmed-7787206
institution National Center for Biotechnology Information
language English
publishDate 2020
publisher Termedia Publishing House
record_format MEDLINE/PubMed
spelling pubmed-77872062021-01-11 Focal low-dose-rate prostate brachytherapy for low- and intermediate-risk prostate cancer Kunogi, Hiroaki Wakumoto, Yoshiaki Kawamoto, Terufumi Oshima, Masaki Horie, Shigeo Sasai, Keisuke J Contemp Brachytherapy Original Paper PURPOSE: To prospectively investigate the efficacy and feasibility of focal low-dose-rate (LDR) prostate brachytherapy for low- and intermediate-risk prostate cancer. MATERIAL AND METHODS: Between October 2014 and May 2019, nineteen low- and intermediate-risk prostate cancer patients who presented with abnormality on both diffusion-weighted and T2-weighted magnetic resonance imaging (MRI) underwent focal LDR brachytherapy at our institution. Focal gross tumor volume (F-GTV) was delineated on transrectal ultrasound, based on abnormality seen on fused T2-weighted MRI. F-GTV was expanded by 5 mm, as a safety margin, to create focal clinical target volume (F-CTV). Prescribed dose to F-CTV was 145 Gy. Biochemical recurrence (BCR) was determined using Phoenix criterion (prostate specific antigen nadir + 2 ng/ml). Pre- and post-implant dosimetry data were compared using non-parametric Wilcoxon’s rank sum test. Treatment-related toxicities were evaluated using common terminology criteria for adverse events. RESULTS: Mean F-CTV D(90%) was significantly lower in the post-implant evaluation than in intraoperative planning (p = 0.004). On post-implant dosimetry, the mean D(90%) for F-GTV and mean V(100%) for the entire prostate were 222 Gy and 35%, respectively. Median follow-up time for all patients was 31 months. BCR occurred in one patient after 23 months. Kaplan-Meier 2-year BCR-free rate was 92.9% (95% confidence interval [CI]: 79.4-100%). No patients had grade 1 or greater gastrointestinal toxicity. Three patients who were taking α-blockers to treat benign prostatic hyperplasia (present before brachytherapy), experienced no treatment-related genitourinary toxicities. Two patients suffered from temporary grade 2 urinary frequency. None of the remaining patients experienced grade 2 or higher genitourinary toxicity. CONCLUSIONS: Focal LDR prostate brachytherapy appears acceptable for MRI-based index tumors, with a low cumulative incidence of BCR. Such brachytherapy might offer a feasible minimally invasive therapeutic option for localized prostate cancer. Termedia Publishing House 2020-12-16 2020-12 /pmc/articles/PMC7787206/ /pubmed/33437303 http://dx.doi.org/10.5114/jcb.2020.101688 Text en Copyright © 2020 Termedia http://creativecommons.org/licenses/by-nc-sa/4.0/ This is an Open Access article distributed under the terms of the Creative Commons Attribution-NonCommercial-ShareAlike 4.0 International (CC BY-NC-SA 4.0). License (http://creativecommons.org/licenses/by-nc-sa/4.0/)
spellingShingle Original Paper
Kunogi, Hiroaki
Wakumoto, Yoshiaki
Kawamoto, Terufumi
Oshima, Masaki
Horie, Shigeo
Sasai, Keisuke
Focal low-dose-rate prostate brachytherapy for low- and intermediate-risk prostate cancer
title Focal low-dose-rate prostate brachytherapy for low- and intermediate-risk prostate cancer
title_full Focal low-dose-rate prostate brachytherapy for low- and intermediate-risk prostate cancer
title_fullStr Focal low-dose-rate prostate brachytherapy for low- and intermediate-risk prostate cancer
title_full_unstemmed Focal low-dose-rate prostate brachytherapy for low- and intermediate-risk prostate cancer
title_short Focal low-dose-rate prostate brachytherapy for low- and intermediate-risk prostate cancer
title_sort focal low-dose-rate prostate brachytherapy for low- and intermediate-risk prostate cancer
topic Original Paper
url https://www.ncbi.nlm.nih.gov/pmc/articles/PMC7787206/
https://www.ncbi.nlm.nih.gov/pubmed/33437303
http://dx.doi.org/10.5114/jcb.2020.101688
work_keys_str_mv AT kunogihiroaki focallowdoserateprostatebrachytherapyforlowandintermediateriskprostatecancer
AT wakumotoyoshiaki focallowdoserateprostatebrachytherapyforlowandintermediateriskprostatecancer
AT kawamototerufumi focallowdoserateprostatebrachytherapyforlowandintermediateriskprostatecancer
AT oshimamasaki focallowdoserateprostatebrachytherapyforlowandintermediateriskprostatecancer
AT horieshigeo focallowdoserateprostatebrachytherapyforlowandintermediateriskprostatecancer
AT sasaikeisuke focallowdoserateprostatebrachytherapyforlowandintermediateriskprostatecancer