MRI findings of radiation-induced changes in the urethra and periurethral tissues after treatment for prostate cancer

A diagnostic approach of various urethral diseases using multimodal imaging findings: comprehensive overview

In clinical practice, urethral diseases are not as frequent as conditions affecting other components of the urinary system. Radiological imaging tests, such as retrograde urethrography, CT, MRI, and PET/CT, along with patient history, are crucial for accurately assessing relatively rare urethral lesions. This article aimed to provide a comprehensive overview of urethral lesions, from traumatic changes to neoplasms, and discuss the multimodal imaging findings of various urethral lesions that radiologists should know. To this end, the normal imaging anatomy of the urethra and a step-by-step approach that can be used in clinical practice have been presented to help in the systematic understanding of urethral lesions.

Impact of treatment modality on pelvic floor dysfunction among uterine cancer survivors

OBJECTIVE

Pelvic floor dysfunction is a common adverse effect of uterine cancer treatment. In this study we compared patient-reported outcomes regarding pelvic floor dysfunction among uterine cancer survivors after hysterectomy and bilateral salpingo-oophorectomy, surgery and brachytherapy, or surgery and external beam radiotherapy with or without brachytherapy versus women who had a hysterectomy for benign indications.

METHODS

We used the validated 20-item Pelvic Floor Distress Inventory to assess lower urinary distress, colorectal distress, and pelvic organ prolapse dysfunction in each treatment group. Pelvic floor dysfunction-related quality of life in these domains was compared across treatment modalities using the Pelvic Floor Impact Questionnaire-7. Treatment type, body mass index, comorbidities, and number of vaginal births were obtained from medical records. A zero-inflated negative binomial regression model was used to assess the association of treatment regimens and covariates relative to the non-cancer cohort.

RESULTS

A total of 309 surveys were analyzed. The median age of the patients at surgery was 58 years (range 20-87) and the median age at survey completion was 66 years (range 34-92). Most participants reported experiencing at least one symptom of pelvic floor dysfunction (76% by Pelvic Floor Distress Inventory-2). The type of treatment had no effect on overall pelvic floor dysfunction on multivariate analysis (all p>0.05). Worse urinary-related symptoms were associated with higher body mass index at surgery (OR 1.41), higher age at time of survey (OR 1.07), and higher numbers of vaginal births (OR 1.43) (all p<0.05).

CONCLUSIONS

Overall, pelvic floor dysfunction did not significantly vary by treatment modality. Our findings suggest complex interactions among age, body mass index, and parity as to how uterine cancer treatment affects pelvic floor quality of life, which should be considered in the choice of treatment strategy and patient counseling.

Sexual Health Dysfunction After Radiotherapy for Gynecological Cancer: Role of Physical Rehabilitation Including Pelvic Floor Muscle Training

Introduction

The present study aims to describe: 1. How the side effects of radiotherapy (RT) could impact sexual health in women; 2. The effectiveness of physical rehabilitation including pelvic floor muscle training (PFMT) in the management of sexual dysfunction after RT.

Materials and Methods

Search keys on PubMed, Web of Science, Scopus, PEDro, and Cochrane were used to identify studies on women treated with radical or adjuvant RT and/or brachytherapy for gynecological cancers with an emphasis on vulvo-vaginal toxicities and PFMT studies on sexual dysfunction for this group of women.

Results

Regarding the first key question, we analyzed 19 studies including a total of 2,739 women who reported vaginal dryness, stenosis, and pain as the most common side effects. Reports of dosimetric risk factors and dose-effect data for vaginal and vulvar post-RT toxicities are scant. Only five studies, including three randomized controlled trials (RCTs), were found to report the effect of PFMT alone or in combination with other treatments. The results showed some evidence for the effect of training modalities including PFMT, but to date, there is insufficient evidence from high-quality studies to draw any conclusion of a possible effect.

Conclusions

Gynecological toxicities after RT are common, and their management is challenging. The few data available for a rehabilitative approach on post-actinic vulvo-vaginal side effects are encouraging. Large and well-designed RCTs with the long-term follow-up that investigate the effect of PFMT on vulvo-vaginal tissues and pelvic floor muscle function are needed to provide further guidance for clinical management.

Randomised controlled trial to investigate the effectiveness of the symptom management after radiotherapy (SMaRT) group intervention to ameliorate lower urinary tract symptoms in men treated for prostate cancer

PURPOSE

To evaluate the effectiveness of the symptom management after radiotherapy (SMaRT) group intervention to improve urinary symptoms in men with prostate cancer.

METHODS

The randomised controlled trial (RCT) recruited men from one radiotherapy centre in the UK after curative radiotherapy or brachytherapy and with moderate to severe urinary symptoms defined as scores ≥ 8 on the International Prostate Symptom Score (IPSS) questionnaire. Sixty-three men were randomised either; to SMaRT, a 10-week symptom-management intervention including group support, education, pelvic floor muscle exercises, or a care-as-usual group. The primary outcome was the IPSS at 6 months from baseline assessment. Secondary outcomes were IPSS at 3 months, and International Continence Society Male Short Form (ICS), European Organisation for Research and Treatment of Cancer Quality of Life prostate scale (EORTC QLQ-PR25), EORTC QLQ-30 and Self-Efficacy for Symptom Control Inventory (SESCI) at 3 and 6 months from baseline. Analysis of covariance (ANCOVA) was used to analyse the effect of the intervention.

RESULTS

SMaRT group intervention did not improve urinary symptoms as measured by IPSS at 6-months. The adjusted difference was - 2.5 [95%CI - 5.0 to 0.0], p = 0.054. Significant differences were detected at 3 months in ICS voiding symptoms (- 1.1 [- 2.0 to - 0.2], p = 0.017), ICS urinary incontinence (- 1.0 [- 1.8 to - 0.1], p = 0.029) and SESCI managing symptoms domain (13.5 [2.5 to 24.4], p = 0.017). No differences were observed at 6 months.

CONCLUSIONS

SMaRT group intervention provided short-term benefit in urinary voiding and continence and helped men manage symptoms but was not effective long term.

Management of Lower Urinary Tract Symptoms after Prostate Radiation

PURPOSE OF REVIEW

To present urologists with guidance on how to approach and manage lower urinary tract symptoms (LUTS) in patients who have undergone radiation therapy (RT) for prostate cancer.

RECENT FINDINGS

There are few studies that specifically examine treatment approaches for LUTS in patients who have undergone prostate cancer RT. LUTS after prostate RT are unique when compared to de novo LUTS. Understanding these distinctions is important for urologists' practice as well as patients' quality of life. Discussion of the risks and management of post-RT LUTS should be included in the shared decision-making process when counseling patients on various treatment options for prostate cancer. Further studies evaluating treatments for storage and voiding symptoms after RT are needed to help guide future care.

Image-guided percutaneous cryo-ablation of peri-urethral unresectable recurrent pelvic malignancy: A case report and brief review

Recurrent or metastatic peri-urethral pelvic malignancies are a difficult-to-treat entity. Re-resection is recommended when possible but is frequently unfavorable due to scar tissue, fibrosis, and obliteration of tissue planes following previous interventions such as surgical resection and/or radiation therapy. Curative options for patients that have unresectable cancer are limited. Cryo-ablation has been extensively studied in the treatment of unresectable renal, liver and lung malignancies and has the potential to provide definitive treatment for recurrent pelvic malignancy. There is a paucity of reports of salvage cryo-ablation in patients with recurrent pelvic malignancies, as most of these tumors are located close to critical structures that could be irreversibly injured by thermal ablation and are hence treated with some form of radiation therapy. But, for patients who fail surgical and radiation treatments, options are limited. Here, we describe two cases of regional tumor recurrence in the pelvis treated with percutaneous cryoablation using protective techniques to avoid thermal injury to adjacent structures. In each case, cryo-ablation was performed successfully despite extensive previous surgical and radiation interventions. Salvage cryo-ablation resulted in a positive clinical and imaging response with an improvement in quality of life and absence of recurrence on follow-up imaging which continues to persist at the writing of this manuscript about 8 and 12-months following treatment.

Reliability of ultrasound imaging of pelvic floor morphology and function among females who have undergone pelvic radiotherapy

AIMS

To investigate the intra- and inter-rater reliability of two-dimensional (2D) transperineal ultrasound imaging (USI) measures of bladder wall thickness (BWT), urethral length (UL), and parameters related to levator plate length (LP) and transient changes in LP during pelvic floor muscle (PFM) contraction, and on Valsalva in women who received radiation therapy (RT) for treatment of pelvic cancer.

METHODS

Twenty women with a history of RT for the treatment of pelvic cancer were assessed independently by two raters on the same day. Five outcomes were assessed for reliability: BWT, UL, and LP at rest (LP-R), during a maximal voluntary contraction of the PFMs (LP-MVC), and during a maximal-effort Valsalva maneuver (LP-MVM). Reliability was determined using intra-class correlation coefficients (ICC) and Bland-Altman analyses. Measurement error was determined using standard error of the measurement (SEM) and minimal detectable difference.

RESULTS

Intra-rater reliability was very good for LP-R, LP-MVC, LP-MVM, and UL (ICC: 0.97 [0.93-0.99], 0.95 [0.88-0.98], 0.84 [0.59-0.94], and 0.96 [0.89-0.98], respectively). Inter-rater reliability was very good for LP-R (ICC: 0.82 [0.55-0.93]), and good for LP-MVC, LP-MVM, and UL (ICC: 0.79 [0.46-0.92], 0.79 [0.49-0.92], and 0.75 [0.36-0.90], respectively). BWT had poor intra- and inter-rater reliability. The variability between measurements was the smallest for LP-R, LP-MVC, and UL for intra-rater assessments, and for LP-R and UL for inter-rater assessments. SEM values for intra-rater assessments were LP-R: 1.5 mm, LP-MVC: 1.84 mm, LP-MVM: 4.33 mm, and UL: 1.16 mm.

CONCLUSIONS

Although these results support the reliability of 2D-transperineal USI for the evaluation of UL and PFM parameters, they do not support its use for the assessment of BWT.

Can radiation-induced lower urinary tract disease be ameliorated in patients treated for pelvic organ cancer: ICI-RS 2019?

Aims

This article reviews the clinical outcomes and basic science related to negative effects of radiotherapy (RT) on the lower urinary tract (LUT) when used to treat pelvic malignancies.

Methods

The topic was discussed at the 2019 meeting of the International Consultation on Incontinence―Research Society during a “think tank” session and is summarized in the present article.

Results

RT is associated with adverse effects on the LUT, which may occur during treatment or which can develop over decades posttreatment. Here, we summarize the incidence and extent of clinical symptoms associated with several modes of delivery of RT. RT impact on normal tissues including urethra, bladder, and ureters is discussed, and the underlying biology is examined. We discuss innovative in vivo methodologies to mimic RT in the laboratory and their potential use in the elucidation of mechanisms underlying radiation‐associated pathophysiology. Finally, emerging questions that need to be addressed through further research are proposed.

Conclusions

We conclude that RT‐induced negative effects on the LUT represent a significant clinical problem. Although this has been reduced with improved methods of delivery to spare normal tissue, we need to (a) discover better approaches to protect normal tissue and (b) develop effective treatments to reverse radiation damage.

Apical periurethral transition zone lesions: MRI and histology findings

PURPOSE

Apical periurethral transition zone (TZ) cancers can pose unique problems for surgery and radiation therapy. Here, we describe the appearance of such cancers on multiparametric MRI (mpMRI) and correlate this with histopathology derived from MRI-targeted biopsy.

MATERIALS AND METHODS

Between May 2011 and January 2019, a total of 4381 consecutive patients underwent 3 T mpMRI. Of these, 53 patients with 58 apical periurethral TZ lesions underwent TRUS/MRI fusion-guided biopsy and 12-core systematic TRUS-guided biopsy. Correlation was made with patient age, PSA, PSA density, whole prostate volume, and Gleason scores.

RESULTS

A total 53 men (median age 68 years, median PSA 7.94 ng/ml) were identified as having at least one apical periurethral TZ lesion on mpMRI and 5 (9%) patients had more than one apical periurethral lesion. Thus, 58 lesions were identified in 53 patients. Of these 37/53 patients (69%) and 40/58 lesions were positive at biopsy for prostate cancer. Seven were diagnosed by 12-core systematic TRUS-guided biopsy and 34 were diagnosed by TRUS/MRI fusion-guided biopsy. Gleason score was ≥ 3 + 4 in 34/58 (58%) lesions.

CONCLUSION

Identification of apical periurethral TZ prostate cancers is important to help guide surgical and radiation therapy as these tumors are adjacent to critical structures. Because of the tendency to undersample the periurethral zone during TRUS biopsy, MRI-guided biopsy is particularly helpful for detecting apical periurethral TZ prostate cancers many of which prove to be clinically significant.

Magnetic Resonance Imaging Assessment After Therapy in Prostate Cancer

Prostate cancer is the fifth leading cause of death worldwide. A variety of treatment options is available for localized prostate cancer and may range from active surveillance to focal therapy or whole gland treatment, that is, surgery or radiotherapy. Serum prostate-specific antigen levels are an important tool to monitor treatment success after whole gland treatment, unfortunately prostate-specific antigen is unreliable after focal therapy. Multiparametric magnetic resonance imaging of the prostate is rapidly gaining field in the management of prostate cancer and may play a crucial role in the evaluation of recurrent prostate cancer. This article will focus on postprocedural magnetic resonance imaging after different forms of local therapy in patients with prostate cancer.

DW-MRI predictive factors for radiation-induced vaginal stenosis in patients with cervical cancer

AIM

To find diffusion-weighted (DW) magnetic resonance imaging (MRI) parameters predictive for radiation-induced vaginal stenosis (VS) in locally advanced cervical cancer (LACC) treated with neoadjuvant chemoradiation therapy (CRT).

MATERIALS AND METHODS

Retrospective analysis of 43 patients with LACC who underwent 1.5 T DW-MRI before (baseline), after 2 weeks (early), and at the end of CRT (final). At MRI, vaginal length, thickness, width, and cervical tumour volume (TV) were measured. Vaginal signal intensity at DW-MRI was analysed at final MRI. CRT-induced VS was graded using Common Terminology Criteria for Adverse Events (CTCAE) v4.03. Correlations between DW-MRI and clinical data were made using Wilcoxon's test, Mann-Whitney test, Fisher's exact test, or chi-squared test as appropriate. Receiver operating characteristic (ROC) curves were generated for variables to evaluate diagnostic ability to predict CRT-induced VS using a logistic regression model.

RESULTS

Asymptomatic vaginal toxicity (CTCAE Grade 1) was observed in 14 patients and symptomatic CRT-induced VS (CTCAE Grade ≥2) was detected in 29 patients. Baseline TV was higher in Grade 1 than in Grade ≥2 (p=0.013). Median vaginal length, thickness, and width decreased between baseline and final MRI in all patients (p<0.0001) without significant variances between CTCAE grades. Significant differences were observed in DW-MRI patterns (p<0.0001). In Grade ≥2, DWI showed signal loss of vaginal mucosa in 17 patients (63%) and diffuse restricted diffusion of vaginal wall in eight patients (30%). AUC was 0.938 (coefficient=4.72; p<0.001) for DWI and 0.712 (coefficient=-2.623×10 ^-5; p=0.004) for TV.

CONCLUSIONS

This is the first study using DW-MRI for predicting CRT-induced VS. DWI is useful tool in patients with LACC after CRT for early prevention and management strategies for VS.

Clinical Anastomotic Leakage After Rectal Cancer Resection Can Be Predicted by Pelvic Anatomic Features on Preoperative MRI Scans: A Secondary Analysis of a Randomized Controlled Trial

BACKGROUND

We demonstrated previously that radiation proctitis induced by preoperative radiotherapy is a predisposing factor for clinical anastomotic leakage in patients undergoing rectal cancer resection. Quantitative measurement of radiation proctitis is needed.

OBJECTIVE

This study aimed to quantitate the changes of anatomic features caused by preoperative radiotherapy for rectal cancer and evaluate its ability to predict leakage.

DESIGN

It was a secondary analysis of a randomized controlled trial (NCT01211210). MRI variables were retrospectively assessed.

SETTINGS

The study was conducted in the leading center of the trial, which is a tertiary GI hospital.

PATIENTS

Patients undergoing preoperative chemoradiation with sphincter-preserving surgery were included.

MAIN OUTCOME MEASURES

Anatomic features were measured by preradiotherapy and postradiotherapy MRI. Univariate analyses were used to identify prognostic factors. Receiver operating characteristic curves were constructed to determine the cutoff value of the changes of MRI variables in predicting leakage.

RESULTS

Eighteen (14.4%) of the 125 included patients developed clinical anastomotic leakage. Baseline characteristics were comparable between leakage group and nonleakage group. Relative increments of width of presacral space, thickness of rectal wall, and distal end of sigmoid colon discriminate between the 2 groups better than random chance. Relative increments of width of presacral space was the best performing predictor, with area under the curve of 0.722, sensitivity of 66.7%, specificity of 72.0%, and positive and negative predictive value of 28.6% and 92.8%.

LIMITATIONS

The study was limited by its small sample size and retrospective design.

CONCLUSIONS

Increments of the width of the presacral space, thickness of rectal wall, and distal part of the sigmoid colon helps to identify individuals not at risk for clinical anastomotic leakage after rectal cancer resection. The first variable is the strongest predictor. Changes of these variables should be taken into consideration when evaluating the application of defunctioning stoma. See Video Abstract at http://links.lww.com/DCR/B23.

CLINICAL TRIALS IDENTIFIER

NCT1211210. LAS FUGAS ANASTOMÓTICAS CLÍNICAS DESPUÉS DE LA RESECCIÓN DEL CÁNCER DEL RECTO PUEDEN PREDECIRSE POR LAS CARACTERÍSTICAS ANATÓMICAS PÉLVICAS EN LAS IMAGENES DE RESONANCIA MAGNÉTICA PREOPERATORIA: UN ANÁLISIS SECUNDARIO DE UN ESTUDIO CONTROLADO ALEATORIZADO:: Anteriormente demostramos que la proctitis inducida por la radiación de radioterapia preoperatoria es un factor predisponente para la fuga anastomótica clínica en pacientes sometidos a resección de cáncer rectal. Es necesaria la medición cuantitativa de la proctitis por radiación.Este estudio tuvo como objetivo cuantificar los cambios en las características anatómicas causados por la radioterapia preoperatoria para el cáncer de recto y evaluar su capacidad para predecir las fugas anastomoticas.Fue un análisis secundario de un estudio controlado aleatorio (NCT01211210). Los variables de imagines de resonancia magnetica se evaluaron retrospectivamente.Se llevó a cabo en el centro principal del estudio, que es un hospital gastrointestinal terciario.Se incluyeron pacientes sometidos a quimiorradiación preoperatoria con cirugía conservadora del esfínter.Las características anatómicas se midieron mediante imagines de resonancia magnetica previa y posterior a la radioterapia. Se utilizaron análisis univariados para identificar los factores pronósticos. Las curvas de características operativas del receptor se construyeron para determinar el valor de corte de los cambios de los variables de resonancia magnetica en la predicción de fugas.Dieciocho (14.4%) de los 125 pacientes incluidos desarrollaron fugas anastomóticas clínicas. Las características basales fueron comparables entre el grupo de fugas y el grupo de no fugas. Los incrementos relativos del ancho del espacio presacro, el grosor de la pared rectal y distal del colon sigmoide discriminan entre los dos grupos mejor que la posibilidad aleatoria. Los incrementos relativos del ancho del espacio presacro fueron el mejor pronóstico con un AUC de 0.722, sensibilidad del 66.7%, especificidad del 72.0%, valor predictivo positivo y negativo del 28.6% y 92.8%.Estaba limitado por el tamaño de muestra pequeño y el diseño retrospectivo.Los incrementos en el ancho del espacio presacro, el grosor de la pared rectal y la parte distal del colon sigmoide ayudan a identificar a las personas que no tienen riesgo de fuga anastomótica clínica después de la resección del cáncer rectal. La primera variable es el predictor más fuerte. Los cambios de estos variables deben tenerse en cuenta al evaluar la aplicación del estoma para desvio. Vea el Resumen del Video en http://links.lww.com/DCR/B23.

Changes in lower urinary tract symptoms after iodine-125 brachytherapy for prostate cancer

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Patients who received BT experienced acute urinary morbidity 3 months after BT of the prostate.

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Acute urinary symptoms gradually improved with time and returned to BL at 36 months.

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Storage symptoms take longer to return to BL compared with voiding symptoms.

Purpose

To investigate chronological changes in lower urinary tract symptoms (LUTS) in patients who received iodine-125 brachytherapy (BT) for prostate cancer.

Methods

We enrolled 706 patients who received BT. Of these, 265 (38%) received BT combined with external beam radiation therapy (EBRT). An International Prostate Symptom Score (IPSS), IPSS quality of life (IPSS-QOL) score, and overactive bladder symptom score (OABSS) were recorded before BT (baseline, BL), and 1, 3, 6, 12, 24, 36, 48, and 60 months after BT. The sum of frequency (2), urgency (4) and nocturia (7) of the IPSS questionnaire was defined as the storage symptoms score, whereas the sum of emptying (1), intermittency (3), weak stream (5), and hesitancy (6) was defined as the voiding symptom score.

Results

Total IPSS significantly increased at 3 months following BT compared with BL (mean score: 17.1 vs. 7.99, P < 0.001) and returned to BL by 36 months. The storage symptom score did not return to BL 36 months after BT. Total OABSS significantly increased 3 months after BT compared with BL (mean score: 6.52 vs. 3.45, P < 0.001), and returned to BL 48 months after BT. The IPSS-QOL score was the highest score (mean score: 2.46 vs. 3.9, P < 0.001) 3 months after BT and returned to BL 48 months after BT, however the IPSS-QOL score was lower than BL (mean score: 2.01 vs 2.46, P < 0.001) at 60 months. The risk factors for LUTS within 1 year after BT were BL IPSS (P < 0.001) and PV (P < 0.001). Patients who received combined EBRT experienced transient storage symptoms 24 and 36 months after BT, whereas those who received BT alone did not. However, the storage symptom score of the patients who received combined EBRT was improving 48 months after BT and eventually showed no significant difference compared with those treated with BT alone.

Conclusion

Three months after BT, LUTS, including storage symptoms, deteriorated the most but improved with time. The urinary symptom in patients who received combined EBRT can potentially flare again in 24 and 36 months after BT. Knowledge of changes in LUTS associated with BT may influence treatment recommendations and enable patients to make better-informed decisions.

Multiparametric Magnetic Resonance Imaging of Recurrent Prostate Cancer

There is growing consensus that multiparametric magnetic resonance imaging (mpMRI) is an effective modality in the detection of locally recurrent prostate cancer after prostatectomy and radiation therapy. The emergence of magnetic resonance (MR)-guided focal therapies, such as cryoablation, high-intensity focused ultrasound, and laser ablation, have made the use of mpMRI even more important, as the normal anatomy is inevitably altered and the detection of recurrence is made more difficult. The aim of this article is to review the utility of mpMRI in detecting recurrent prostate cancer in patients following radical prostatectomy, radiation therapy, and focal therapy and to discuss expected post-treatment mpMRI findings, the varied appearance of recurrent tumors, and their mimics.

Acute Urinary Morbidity Following Stereotactic Body Radiation Therapy for Prostate Cancer with Prophylactic Alpha-Adrenergic Antagonist and Urethral Dose Reduction

BACKGROUND

Stereotactic body radiation therapy (SBRT) delivers high doses of radiation to the prostate while minimizing radiation to the adjacent critical organs. Large fraction sizes may increase urinary morbidity due to unavoidable treatment of the prostatic urethra. This study reports rates of acute urinary morbidity following SBRT for localized prostate cancer with prophylactic alpha-adrenergic antagonist utilization and urethral dose reduction (UDR).

METHODS

From April 2013 to September 2014, 102 patients with clinically localized prostate cancer were treated with robotic SBRT to a total dose of 35-36.25 Gy in five fractions. UDR was employed to limit the maximum point dose of the prostatic urethra to 40 Gy. Prophylactic alpha-adrenergic antagonists were initiated 5 days prior to SBRT and continued until resolution of urinary symptoms. Quality of life (QoL) was assessed before and after treatment using the American Urological Association Symptom Score (AUA) and the Expanded Prostate Cancer Index Composite-26 (EPIC-26). Clinical significance was assessed using a minimally important difference (MID) of one half SD change from baseline.

RESULTS

One hundred two patients underwent definitive prostate SBRT with UDR and were followed for 3 months. No patient experienced acute urinary retention requiring catheterization. A mean baseline AUA symptom score of 9.06 significantly increased to 11.83 1-week post-SBRT (p = 0.0024) and 11.84 1-month post-SBRT (p = 0.0023) but returned to baseline by 3 months. A mean baseline EPIC-26 irritative/obstructive score of 87.7 decreased to 74.1 1-week post-SBRT (p < 0.0001) and 77.8 1-month post-SBRT (p < 0.0001) but returned to baseline at 3 months. EPIC-26 irritative/obstructive score changes were clinically significant, exceeding the MID of 6.0. At baseline, 8.9% of men described their urinary function as a moderate to big problem, and that proportion increased to 37.6% 1 week following completion of SBRT before returning to baseline by 3 months.

CONCLUSION

Stereotactic body radiation therapy for localized prostate cancer with utilization of prophylactic alpha-adrenergic antagonist and UDR was well tolerated as determined by acute urinary function and bother, and symptoms were comparable to those observed following conventionally fractionated external beam radiation therapy (EBRT). Longer follow-up is required to assess long-term toxicity and efficacy following SBRT with UDR.

Predictive factors for urinary toxicity after iodine-125 prostate brachytherapy with or without supplemental external beam radiotherapy

PURPOSE

We examined the factors associated with urinary toxicities because of brachytherapy with iodine-125 with or without supplemental external beam radiotherapy (EBRT) for prostate cancer.

METHODS AND MATERIALS

We investigated 1313 patients with localized prostate cancer treated with iodine-125 brachytherapy with or without supplemental EBRT between 2003 and 2009. The International Prostate Symptom Score (IPSS) and Common Terminology Criteria for Adverse Events data were prospectively determined. Patients, treatment, and implant factors were investigated for their association with urinary toxicity or symptoms.

RESULTS

IPSS resolution was not associated with biologically effective dose (BED). Baseline IPSS, total needles, and the minimal dose received by 30% of the urethra had the greatest effect according to multivariate analysis (MVA). Urinary symptom flare was associated with baseline IPSS, age, BED, and EBRT on MVA. Urinary symptom flare and urinary Grade 2 or higher (G2+) toxicity occurred in 51%, 58%, and 67% (p = 0.025) and 16%, 22%, and 20% (p = 0.497) of the <180, 180-220, and >220 Gy BED groups, respectively. Urinary G2+ toxicity was associated with baseline IPSS, neoadjuvant androgen deprivation therapy (NADT), and seed density on MVA. When we divided patients into four groups according to prostate volume (<30 cc or ≥30 cc) and NADT use, urinary G2+ toxicity was most commonly observed in those patients with larger prostates who received NADT, and least in the patients with smaller prostates and no NADT.

CONCLUSIONS

NADT was associated with urinary G2+ toxicity. Higher dose and supplemental EBRT did not appear to increase moderate to severe urinary toxicities or time to IPSS resolution; however, it influenced urinary symptom flare.