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One of the most challenging phases in interstitial brachytherapy is the placement of the needles. In these medical procedures, the needles are inserted inside the tissue to guide the positioning of the radioactive sources. The low-dose-rate radioactive sources are placed inside the tissue permanently, whereas a radioactive source in the high-dose-rate brachytherapy is temporarily placed in the desired positions so that the delivery of the prescription dose to the clinical targets can be achieved. Consequently, the precise needle placement directly influences the radiation dose delivery and the treatment outcomes of patients. Any deviation from the desired position of the radioactive sources can cause a suboptimal dose distribution and inadequate tumor coverage. Therefore, it is of significant importance to develop a robust and sophisticated tool that can perform the automatic needle placement with a high level of accuracy for different medical procedures and conditions. In this study, we propose a novel concept for the automatic needle insertion using a new miniature automated robotic system. The mathematical model of this system was presented in detail, allowing the implementation of the model predictive control that can be used to govern the mechanism. The purpose of this approach was to minimize the lateral components of the generalized reactive force which is responsible for the tissue displacement and, consequently, for the needle deflection. The proposed approach was designed to predict and to compensate for the unmeasured disturbances, such as needle deflection or tissue resistance and reactive force, and it was capable of correcting them without waiting until the effect appears at the output of the system causing the needle deviation from the desired positions. The extensive simulation of the system was presented to evaluate the feasibility of the method and the parameters of interest including displacements, system errors and system responses to the change in the environmental conditions. [ABSTRACT FROM AUTHOR]

Purpose: To evaluate a transrectal ultrasound (TRUS)-fluoroscopy fusion-based intraoperative dosimetry system. Method and Materials: Twenty-five patients were treated for prostate cancer with Pd-103 implantation. After the execution of the treatment plan, two sets of TRUS images were collected using the longitudinal and axial transducers of a biplanar probe. Then, three fluoroscopic images were acquired at 0, -15 and +15 degrees . The three-dimensional locations of all implanted seeds were reconstructed from fluoroscopic images. A subset of the implanted seeds was manually identified in TRUS images and used as fiducial markers to perform TRUS-fluoroscopy fusion. To improve the implant quality, additional seeds were placed if adverse isodose patterns were identified during visual inspection. If additional seeds were placed, intraoperative dosimetry was repeated. Day 0 computed tomography-based dosimetry was compared with final intraoperative dosimetry to validate dosimetry achieved in the implant suite. Results: An average of additional 4.0 seeds was implanted in 16 patients after initial intraoperative dose evaluation. Based on TRUS-fluoroscopy fusion-based dosimetry, the V100 improved from 86% to 93% (p = 0.005), whereas D90 increased from 94% to 109% (p = 0.011) with the guided additional seed implantation. No statistical difference was observed in V200 and V300 values. V100 and D90 values were 95 +/- 4% and 120 +/- 24%, respectively, based on the final intraoperative dosimetry evaluation, compared with 95 +/- 4% and 122 +/- 24%, respectively, based on Day 0 computed tomography-based dosimetry. Conclusions: Implantation of extra seeds based on TRUS-fluoroscopy fusion-based intraoperative dosimetry can improve the final V100 and D90 values with minimal increase in V200 and V300 values. [ABSTRACT FROM AUTHOR]

Purpose Recent retrospective data suggest that brachytherapy (BT) boost may confer a cancer-specific survival benefit in radiation-managed high-risk prostate cancer. We sought to determine whether this survival benefit would extend to the recently defined favorable high-risk subgroup of prostate cancer patients (T1c, Gleason 4 + 4 = 8, PSA < 10 ng/ml or T1c, Gleason 6, PSA > 20 ng/ml). Material and methods We identified 45,078 patients in the Surveillance, Epidemiology, and End Results database with cT1c-T3aN0M0 intermediate- to high-risk prostate cancer diagnosed 2004-2011 treated with external beam radiation therapy (EBRT) only or EBRT plus BT. We used multivariable competing risks regression to determine differences in the rate of prostate cancer-specific mortality (PCSM) after EBRT + BT or EBRT alone in patients with intermediate-risk, favorable high-risk, or other high-risk disease after adjusting for demographic and clinical factors. Results: EBRT + BT was not associated with an improvement in 5-year PCSM compared to EBRT alone among patients with favorable high-risk disease (1.6% vs. 1.8%; adjusted hazard ratio [AHR]: 0.56; 95% confidence interval [CI]: 0.21-1.52, p = 0.258), and intermediate-risk disease (0.8% vs. 1.0%, AHR: 0.83, 95% CI: 0.59-1.16, p = 0.270). Others with high-risk disease had significantly lower 5-year PCSM when treated with EBRT + BT compared with EBRT alone (3.9% vs. 5.3%; AHR: 0.73; 95% CI: 0.55-0.95; p = 0.022). Conclusions: Brachytherapy boost is associated with a decreased rate of PCSM in some men with high-risk prostate cancer but not among patients with favorable high-risk disease. Our results suggest that the recently-defined “favorable high-risk” category may be used to personalize therapy for men with high-risk disease.

Purpose: The use of prostate brachytherapy has continued to decline in the United States. We examined the national practice patterns of both academic and nonacademic practices performing prostate brachytherapy by case volume per year to further characterize the decline and postulate the effect this trend might have on training the next generation of residents.Methods and Materials: Men diagnosed with prostate cancer who had undergone radiation therapy in 2004 to 2012 were identified. The annual brachytherapy case volume at each facility was determined and further categorized into ≤12 cases per year (ie, an average of ≤1 cases per month), 13 to 52 cases per year, and ≥53 cases per year (ie, an average of ≥1 cases per week) in academic practices versus nonacademic practices.Results: In 2004 to 2012, academic practices performing an average of ≤1 brachytherapy cases per month increased from 56.4% to 73.7%. In nonacademic practices, this percentage increased from 60.2% to 77.4% (P<.0001 for both). Practices performing an average of ≥1 cases per week decreased among both academic practices (from 6.7% to 1.5%) and nonacademic practices (from 4.5% to 2.7%).Conclusions: Both academic and nonacademic radiation oncology practices have demonstrated a significant reduction in the use of prostate brachytherapy from 2004 to 2012. With the case volume continuing to decline, it is unclear whether we are prepared to train the next generation of residents in this critical modality. [ABSTRACT FROM AUTHOR]

Purpose: Although level 1 evidence has demonstrated a survival benefit from the addition of androgen deprivation therapy (ADT) to external beam radiation therapy (EBRT) for patients with high-risk prostate cancer, the benefits of ADT with combined EBRT and brachytherapy for high-risk patients are unclear. We examined the association between ADT and overall survival in a national cohort of high-risk patients treated with EBRT with or without brachytherapy., Methods and Materials: We identified 46,325 men in the National Cancer Database with a diagnosis of high-risk prostate cancer (Gleason score 8-10, clinical stage T3-T4, or prostate-specific antigen >20 ng/mL) who were treated with EBRT with or without brachytherapy and ADT from 2004 through 2011. Multivariable Cox regression analysis adjusting for sociodemographic and clinicopathologic factors was used to identify the association between ADT and overall survival., Results: The median follow-up period was 48.6 and 59.2 months for patients treated with EBRT only and combined modality RT, respectively. ADT was associated with an improvement in overall survival for the 85.0% (39,361) of the study cohort who underwent EBRT alone (adjusted hazard ratio 0.91, P=.001) but not for patients treated with combined modality RT (adjusted hazard ratio 1.05, P=.496), with a significant interaction (P interaction =.036)., Conclusions: In contrast to the known survival benefit when ADT is given with EBRT, our results suggest that ADT might not improve survival for high-risk patients who undergo combined EBRT and brachytherapy. Given the significant adverse effects of ADT, in particular, with long-term therapy, a randomized controlled trial of combined EBRT and brachytherapy with or without ADT for select high-risk patients using a noninferiority design should be undertaken., (Copyright © 2017 Elsevier Inc. All rights reserved.)

Purpose: A recent randomized controlled trial demonstrated that the addition of external beam radiation therapy (EBRT) to brachytherapy did not improve progression-free survival in select patients with intermediate-risk prostate cancer. We evaluated whether the addition of EBRT to brachytherapy improves prostate cancer-specific mortality (PCSM) for intermediate- and high-risk disease using a large national database., Methods and Materials: We identified 5836 patients in the Surveillance, Epidemiology, and End Results-Medicare linked database with a diagnosis of National Comprehensive Cancer Network intermediate-risk (Gleason score 7, prostate-specific antigen 10-20 ng/mL, or stage cT2b-T2c) or high-risk (Gleason score 8-10 or prostate-specific antigen >20 ng/mL and stage ≤cT3a) prostate cancer who had undergone brachytherapy, with or without EBRT and androgen deprivation therapy (ADT). Patients were diagnosed from 2004 through 2009. Intermediate-risk patients with Gleason score ≤3+4 and 1 intermediate-risk factor were considered favorable and all others unfavorable. We used multivariable Fine-Gray competing risks regression to study PCSM while adjusting for sociodemographic and clinical factors and ADT use., Results: Overall, 50.3% of intermediate- and high-risk patients who received brachytherapy and EBRT did not have significantly improved PCSM compared with that of the patients who received brachytherapy alone (adjusted hazard ratio [AHR] 1.46, 95% confidence interval [CI] 0.69-3.11; P=.322; 5-year PCSM 2.4% vs 1.0%). This lack of benefit was seen among favorable intermediate-risk (AHR 2.66, 95% CI 0.93-7.62, P=.069; 5-year PCSM 1.3% vs 0.6%), unfavorable intermediate-risk (AHR 0.68, 95% CI 0.16-2.96, P=.612; 5-year PCSM 1.0% vs 1.2%), and high-risk (AHR 1.82, 95% CI 0.67-4.98, P=.242; 5-year PCSM 5.3% vs 2.1%) subgroups., Conclusions: These results suggest that certain patients with intermediate- or high-risk prostate cancer treated with brachytherapy might not benefit from the addition of EBRT. A randomized controlled trial of brachytherapy plus ADT with or without EBRT for unfavorable intermediate- and favorable high-risk organ-confined prostate cancer should be undertaken., (Copyright © 2017 Elsevier Inc. All rights reserved.)

Introduction: We sought to determine whether any sociodemographic disparities are present in the receipt of local treatment for node-positive prostate cancer., Patients and Methods: We identified 9771 patients with clinical N1M0 prostate cancer diagnosed from 1998 to 2012 using the National Cancer Database. We used multivariable logistic regression modeling to identify patient-specific factors that were associated with a reduced likelihood of receiving prostate or pelvic radiation or radical prostatectomy. We also used Cox regression modeling to estimate the differences in overall survival (OS) using these factors., Results: The factors associated with a reduced likelihood of receiving local therapy included black race versus white race (43.6% vs. 49.4%; adjusted odds ratio [AOR], 0.76; P = .001), bottom income quartile versus top quartile (44.7% vs. 52.7%; AOR, 0.69; P = .001), age > 66 years versus ≤ 66 years (40.8% vs. 55.1%; AOR, 0.48; P < .001), diagnosis before 2005 versus after 2005 (30.5% vs. 61.7%; AOR, 0.66; P < .001), and Medicaid or no insurance versus private insurance (41.0% vs. 49.4%; AOR, 0.41; P < .001). Although patients had reduced 5-year OS if they were from lower income quartiles (adjusted hazard ratios [AHRs], 1.18-1.22; P < .05), were older (AHR, 1.82; P < .001), or had Medicaid or no insurance (AHR, 1.24; P = .032), these disparities were no longer present or were smaller in magnitude after adjustment for receipt of local treatment., Conclusion: Significant treatment disparities exist in the receipt of local therapy for node-positive prostate cancer. Given the accumulating evidence supporting this practice, the factors underlying these disparities should be studied and addressed., (Copyright © 2016. Published by Elsevier Inc.)

Magnetic resonance imaging (MRI) simulation and planning for prostate brachytherapy (PBT) may deliver potential clinical benefits but at an unknown cost to the provider and healthcare system. Time-driven activity-based costing (TDABC) is an innovative bottom-up costing tool in healthcare that can be used to measure the actual consumption of resources required over the full cycle of care. TDABC analysis was conducted to compare patient-level costs for an MRI-based versus traditional PBT workflow. TDABC cost was only 1% higher for the MRI-based workflow, and utilization of MRI allowed for cost shifting from other imaging modalities, such as CT and ultrasound, to MRI during the PBT process. Future initiatives will be required to follow the costs of care over longer periods of time to determine if improvements in outcomes and toxicities with an MRI-based approach lead to lower resource utilization and spending over the long-term. Understanding provider costs will become important as healthcare reform transitions to value-based purchasing and other alternative payment models., (Copyright © 2016 American Brachytherapy Society. Published by Elsevier Inc. All rights reserved.)

Purpose: Androgen deprivation therapy (ADT) is not recommended for low-risk prostate cancer because of its lack of benefit and potential for harm. We evaluated the incidence and predictors of ADT use in low-risk disease., Methods and Materials: Using the National Cancer Database, we identified 197,957 patients with low-risk prostate cancer (Gleason score of 3 + 3 = 6, prostate-specific antigen level <10 ng/mL, and cT1-T2a) diagnosed from 2004 to 2012 with complete demographic and treatment information. We used multiple logistic regression to evaluate predictors of ADT use and Cox regression to examine its association with all-cause mortality., Results: Overall ADT use decreased from 17.6% in 2004 to 3.5% in 2012. In 2012, 11.5% of low-risk brachytherapy patients and 7.6% of external beam radiation therapy patients received ADT. Among 82,352 irradiation-managed patients, predictors of ADT use included treatment in a community versus academic cancer program (adjusted odds ratio [AOR], 1.60; 95% confidence interval [CI], 1.50-1.71; P<.001; incidence, 14.0% vs 6.0% in 2012); treatment in the South (AOR, 1.51), Midwest (AOR, 1.81), or Northeast (AOR, 1.90) versus West (P<.001); and brachytherapy use versus external beam radiation therapy (AOR, 1.32; 95% CI, 1.27-1.37; P<.001). Among 25,196 patients who did not receive local therapy, predictors of primary ADT use included a Charlson-Deyo comorbidity score of ≥2 versus 0 (AOR, 1.42; 95% CI, 1.06-1.91; P=.018); treatment in a community versus academic cancer program (AOR, 1.61; 95% CI, 1.37-1.90; P<.001); and treatment in the South (AOR, 1.26), Midwest (AOR, 1.52), or Northeast (AOR, 1.28) versus West (P≤.008). Primary ADT use was associated with increased all-cause mortality in patients who did not receive local therapy (adjusted hazard ratio, 1.28; 95% CI, 1.14-1.43; P<.001) after adjustment for age and comorbidity., Conclusions: ADT use in low-risk prostate cancer has declined nationally but may remain an issue of concern in certain populations and regions., (Copyright © 2017 Elsevier Inc. All rights reserved.)

Transperineal permanent brachytherapy is a safe and effective treatment option for patients with organ-confined prostate cancer. Careful adherence to established brachytherapy standards has been shown to improve the likelihood of procedural success and reduce the incidence of treatment-related morbidity. A collaborative effort of the American College of Radiology (ACR) and the American Brachytherapy Society (ABS) has produced practice parameters for LDR prostate brachytherapy. These practice parameters define the qualifications and responsibilities of all the involved personnel, including the radiation oncologist, physicist and dosimetrist. Factors with respect to patient selection and appropriate use of supplemental treatment modalities such as external beam radiation and androgen suppression therapy are discussed. Logistics with respect to the brachytherapy implant procedure, the importance of dosimetric guidelines, and attention to radiation safety procedures and documentation are presented. Adherence to these parameters can be part of ensuring quality and safety in a successful prostate brachytherapy program., (Copyright © 2016 American Brachytherapy Society and American College of Radiology. Published by Elsevier Inc. All rights reserved.)

Purpose: The long-term prostate cancer-specific survival for patients initially managed with active surveillance for low-risk prostate cancer ranges from 97% to 100%. We characterized factors that are associated with aggressive treatment with radical prostatectomy or radiation for indolent prostate cancer (defined as screening-detected, low-risk disease)., Methods: The Surveillance, Epidemiology, and End Results Program was used to extract a cohort of 39,803 men diagnosed with prostate-specific antigen-detected, low-risk prostate cancer (clinical category T1c, Gleason score ≤6, and prostate-specific antigen <10) from 2004 to 2010. After socioeconomic profiles were generated from county-linked education and income data, multivariable logistic regression was used to determine whether there were any factors associated with high rates of aggressive treatment., Results: The rate of aggressive treatment among all men with indolent prostate cancer was 64.3%. Greater rates of aggressive treatment were experienced by men with high socioeconomic status, Caucasian men, and married men (P < .001 for all cases). The increased adjusted odds for receipt of aggressive therapy were 1.25 (95% confidence interval [CI], 1.17-1.32; P < .001), 1.26 (95% CI, 1.21-1.32; P < .001), and 1.88 (95% CI, 1.80-1.97; P < .001) for men with high socioeconomic status, Caucasian men, and married men, respectively, compared with men with low socioeconomic status, non-Caucasian men, and unmarried men, respectively., Conclusions: Although men with high socioeconomic status, Caucasian men, and married men often receive the highest quality health care and have the best outcomes for many cancers, it seems that they are most at risk for the avoidable potential harms of aggressive treatment of indolent prostate cancer. Future policy should encourage more stringent guidelines for deferred treatment and culturally and sociodemographically competent counseling of active surveillance., (Copyright © 2015 Elsevier Inc. All rights reserved.)