Complications after Prostate Cancer Treatment: Pathophysiology and Repair of Post-Radiation Urethral Stricture Disease.

Radiation therapy (RT) in the management of pelvic cancers remains a clinical challenge to urologists given the sequelae of urethral stricture disease secondary to fibrosis and vascular insults. The objective of this review is to understand the physiology of radiation-induced stricture disease and to educate urologists in clinical practice regarding future prospective options clinicians have to deal with this condition. The management of post-radiation urethral stricture consists of conservative, endoscopic, and primary reconstructive options. Endoscopic approaches remain an option, but with limited long-term success. Despite concerns with graft take, reconstructive options such as urethroplasties in this population with buccal grafts have shown long-term success rates ranging from 70 to 100%. Robotic reconstruction is augmenting previous options with faster recovery times. Radiation-induced stricture disease is challenging with multiple interventions available, but with successful outcomes demonstrated in various cohorts including urethroplasties with buccal grafts and robotic reconstruction.

Evaluation of dosimetric impact of inter-application and intra-application variations in fractionated high-dose-rate intra-cavitary brachytherapy of cervical cancer.

PURPOSE: To evaluate feasibility and safety of execution of optimized intra-cavitary brachytherapy (ICBT) plan of first fraction in subsequent fractions in high-volume, low-resource centers. MATERIAL AND METHODS: This non-randomized prospective study included 30 cervical cancer patients, who underwent 4 fractions of high-dose-rate (HDR)-ICBT in 2 applications, one week apart, 2 fractions per application delivered on two consecutive days. Computed tomography (CT) simulation was done before each fraction, organs at risk (OARs) were contoured on all sets of CT images. Optimized plans were generated for each set of CT images and executed for the treatment. Test treatment plans were retrospectively generated by applying first treatment fraction's dwell times adjusted for decay, and dwell positions of the applicator for subsequent treatment fractions paired t-test was performed to analyze D2cc dose variations of OARs among the paired sets of plans. RESULTS: Comparison between the plans showed daily plans provided lower D2cc to OARs than test plans. In intra-application plan comparison, there was a significant dose reduction to 2 cc sigmoid (p = 0.021) and bladder (p = 0.007) in daily plan. Mean D2cc of optimized and unoptimized plans were 361.35 ±114.01 and 411.70 ±152.73 for sigmoid, and 511.23 ±85.47 cGy and 553.57 ±111.23 cGy for bladder, respectively. In inter-application, D2cc rectum and sigmoid demonstrated a statistically significant dose variation (p = 0.002) and (p = 0.007), with mean D2cc rectum of optimized and unoptimized plans being 401.06 ±83.53 cGy and 452.46 ±123.97 cGy, and of 2 cc sigmoid 340.84 ±117.90 cGy and 387.79 ±141.36 cGy, respectively. CONCLUSIONS: Fractionated HDR brachytherapy amounts to significant variation in OAR doses if re-simulation and re-plan is not performed for every fraction and ICBT application. Therefore, plan of the day with optimization of the doses to target and OARs must be followed for each fraction.