Predictive Factors for Prolonged Urination Disorder After Permanent 125I Brachytherapy for Localized Prostate Cancer

Abstract

The use of permanent radioactive implants to treat clinicallylocalized prostate cancer patients has been increasing rapidly all over the world for the past 20 years. In Japan, prostate brachytherapy (PBT) became an insurance adaptation in 2003 and has become one of the most common treatments for clinically-localized prostate cancer (1) National Comprehensive Cancer Network Clinical Practice Guidelines recommend PBT not only for low-and intermediate-risk groups but also for high-and very high-risk groups in combination with androgen deprivation therapy (ADT) and external beam radiotherapy (EBRT) (2). It is reported that high-dose radiotherapy using low-dose-rate PBT in combination with EBRT and short-term ADT has shown excellent outcomes in high-risk and very highrisk cancer (3, 4).PBT can cause some adverse events. Lower urinary tract symptoms (LUTS) are major complications for men following PBT (5-10). For some patients, International Prostate Symptom Scores (IPSS) quickly return to pretreatment levels, while others require more time. We assessed the change in LUTS after brachytherapy to reveal predictive factors for prolonged urination disorder.To our knowledge, no study has analyzed predictive factors using time-dependent multivariate analysis. Patients and MethodsPatient characteristics. Between July 2004 and December 2014, 404 patients received low-dose-rate PBT at Tokushima University Hospital in Japan and were followed-up for at least 2 years. Clinical characteristics of patients are shown in Table I.Brachytherapy procedure. Pre-planning involved analyzing the prostate in detail by transrectal ultrasonography about 4 weeks before brachytherapy to calculate prostate volume (PV) and plan seed implantation. Brachytherapy was performed using ultrasoundguided, transperineal prostate implantation planned using Interplant software (CMS, St. Louis, MO, USA). For post-planning, about 4 weeks after seed implantation, computed tomography, and radiography of the chest kidneys, ureters, and bladder were performed to calculate the radiation dose to 90% of the prostate volume (D90) and to evaluate seed migration in all patients.Follow-up. All patients were asked to return at 1, 3, and 6 months after seed implantation, and every 6 months thereafter. Patient IPSS was assessed at each visit. PV was measured every 12 months using 755

Sarcopenia and excess visceral fat accumulation negatively affect early urinary function after I‐125 low‐dose‐rate brachytherapy for localized prostate cancer

“…Previous studies have described factors associated with the incidence and resolution of LUTS after LDB, such as baseline score, 20,21 age, 22 greater prostate volume, 4,22 hormone therapy, 4,22 UD30, 21 D90, 4,20 and the number of needles 21 . Sarcopenia and excess accumulation of visceral fat noted herein are new insights toward predicting LUTS after LDB, which may be useful because they can be evaluated in routine practice.…”