Brachytherapy For Prostate Cancer Research Articles

PO0423: Low Dose Rate Brachytherapy for Prostate Cancer: A 20-year Single Institution Experience from the Philippines

PO0423: Low Dose Rate Brachytherapy for Prostate Cancer: A 20-year Single Institution Experience from the Philippines

Mortality rates in radical cystectomy patients with bladder cancer after radiation therapy for prostate cancer.

To conduct a population-based study examining cancer-specific mortality (CSM) and other-cause mortality (OCM) differences in patients with radiation-induced secondary bladder cancer (RT-BCa) vs those with primary bladder cancer (pBCa) undergoing radical cystectomy (RC). Within the Surveillance, Epidemiology, and End Results database (2004-2020), we identified patients with T2-4N0-3M0 bladder cancer treated with RC, who had previously been treated with external beam radiation therapy (EBRT) or brachytherapy for prostate cancer, as well as patients with T2-4N0-3M0 pBCa treated with RC. Cumulative incidence plots and multivariable competing risks regression (CRR) models were used to assess CSM after additional adjustment for OCM. The same methodology was then repeated based on organ-confined (OC: T2N0M0) and non-organ-confined (NOC: T3-4 and/or N1-3) disease. Of 9957 RC patients, RT-BCa was identified in 347 (3%) compared with 9610 (97%) who had pBCa. In multivariable CRR models, no CSM differences were recorded in the overall comparison (P = 0.8), nor in sub-groups based on OC and NOC disease (P = 0.8 and 0.7, respectively). Conversely, multivariable CRR models identified RT-BCa as an independent predictor of 1.3-fold higher OCM in the overall cohort and of 1.5-fold higher OCM in those with NOC disease. In a sensitivity analysis of patients with NOC disease, EBRT was associated with higher OCM rates (hazard ratio 1.5). By contrast, OCM rates were not different in those with OC disease (P = 0.8). Our study showed that RC for RT-BCa was associated with similar CSM rates as RC for pBCa, regardless of disease stage. However, patients who had undergone EBRT exhibited significantly higher OCM in the NOC sub-group.

PO0434: Utilization Rates of Brachytherapy for Prostate Cancer: A Population Based Study in a Canadian Province

PO0434: Utilization Rates of Brachytherapy for Prostate Cancer: A Population Based Study in a Canadian Province

PO0411: Retrospective Analysis of Patients Treated with HDR Brachytherapy for Prostate Cancer

PO0411: Retrospective Analysis of Patients Treated with HDR Brachytherapy for Prostate Cancer

Efficacy of brachytherapy versus radical prostatectomy for localized prostate cancer–propensity score-matched comparison

ObjectiveThe brachytherapy (BT) and radical prostatectomy (RP) are two methods recommended in current guidelines for the treatment of localized prostate cancer (PCa). It is difficult to compare the oncological results of these two treatments because of differences in baseline characteristics and treatment selection.we sought to compare the efficacy of BT and RP after propensity score matching(PSM)analysis.MethodsBetween January 2009 and December 2021, our institution treated 657 patients with localized PCa (BT: n = 198; RP: n = 459)and followed up for > 2 years. Biochemical recurrence was defined as prostate-specific antigen (PSA) levels of nadir plus 2 ng/ml or higher (Phoenix definition) for BT, and as PSA0.2 ng/ml or greater for RP. PSM was applied based on the age, body mass index, PSA, prostate volume, clinical T-stage, Gleason grade, percentage of positive puncture needles ≥ 1/2, maximum tumor diameter ≥ 5 mm, and follow-up period.ResultsMedian follow-up was 63 months for BT and 52 months for RP. After propensity score adjustment, a total of 294 (147 each) patients remained for further analysis.Kaplan–Meier curves showed no statistically significant difference in clinical relapse-free survivals (cRFS) (p = 0.637),overall survival (OS) (p = 0.726),and cancer-specific survival (CSS) (p = 0.505).BT was associated with improved biochemical relapse-free survivals (bRFS) compared to RP (p = 0.022), Logistic multivariate analysis based on the whole cohort revealed that clinical T stage ≥ T2b (p = 0.043) and tumor maximum diameter ≥ 5 mm (p = 0.044) were associated with significantly bRFS.ConclusionThe BT and RP group patients exhibited similar cRFS, OS, and CSS. However, patients in the BT groups exhibited better bRFS than those in the RP group.Clinical T stage ≥ T2b and a maximum tumor diameter ≥ 5 mm were independent prognostic factors.

70 Retrospective Analysis of Patients Treated with HDR Brachytherapy for Prostate Cancer

70 Retrospective Analysis of Patients Treated with HDR Brachytherapy for Prostate Cancer

Design of a seed implantation robot with puncture force and image feedback mechanism for prostate cancer brachytherapy

Design of a seed implantation robot with puncture force and image feedback mechanism for prostate cancer brachytherapy

1131: Similar toxicity in Brachytherapy vs EBRT in prostate cancer: PROMs from single institutional study.

1131: Similar toxicity in Brachytherapy vs EBRT in prostate cancer: PROMs from single institutional study.

Optimized needle configuration for operational seed (ONCOSEED) efficiency and deployment for prostate seed implants

Due to anatomical changes between pre-planning and implantation, there exists a need for tools that can streamline the adjustment of needle and seed configurations in low dose rate brachytherapy for prostate cancer. Specifically, upon taking a second ultrasound on the day of treatment, the distribution of seeds and needles will differ drastically from the original plan. Clinics that employ this method must then spend time and resources to generate a workflow to manipulate the original configuration to the new configuration. ONCOSEED extracts data from VariSeed treatment plans, calculating a labor score (LScore) to optimize adjustments to needle configurations. A case study of three simulated VariSeed treatment plans was used to compare the ONCOSEED software to the manual method of generating a workflow. In the same method that was used at the authors’ clinic, several assistants annotated by hand the original plan to convert it to the new plan. The time taken to do so was recorded and compared to the runtime of the software when generating a workflow for the same plan. Results showed that ONCOSEED was on average 28 times faster than generating a workflow by hand. ONCOSEED enhances the efficiency of seed replacement in LDR brachytherapy, promoting the adoption of adaptive brachytherapy practices.

Duration of α-1 adrenergic antagonist administration after low-dose-rate brachytherapy for prostate cancer.

Urinary dysfunction is an adverse event of low-dose-rate brachytherapy (LDR-BT) in patients with prostate cancer. We aimed to examine the time to α-1 adrenergic antagonist withdrawal after LDR-BT initiation. We retrospectively evaluated 1663 patients who underwent LDR-BT at our hospital during 2004-2022. Overall, 1485/1663 (89.3%) patients were able to stop using α-1 adrenergic antagonists, 1111 (66.8%) of them within 1year of LDR-BT. Risk factors for prolonged time to withdrawal were age ≥70years, taking agents for lower urinary tract symptoms prior to LDR-BT, an International Prostate Symptom Score≥8, an Overactive Bladder Symptom Score≥3 and a residual urine volume≥20ml. Of the patients who were able to stop taking α-1 adrenergic antagonists, 357/1485 (24.0%) required resumption, 218 (61.1%) of whom did so between 1 and 3years after LDR-BT. This period matched the period of transient worsening of the urinary symptom score. Finally, multivariable analysis identified supplemental external beam radiotherapy and an Overactive Bladder Symptom Score≥3 as independent risk factors for α-1 adrenergic antagonist resumption. Withdrawal of α-1 adrenergic antagonists was possible in 66.8% of patients within 1year of LDR-BT. Our results suggest that patients who are older or have pre-treatment LUTS may have prolonged deterioration of urinary dysfunction after treatment. Resumption of α-1 adrenergic antagonists 1-3years after treatment may be associated with urinary symptom flares, and close attention is necessary for patients with supplemental external beam radiotherapy and a high pretreatment Overactive Bladder Symptom Score.

Adaptive approach for tracking movements of biological targets: application to robot-based intervention for prostate cancer.

In this paper, we introduce an advanced robotic system integrated with an adaptive optimization algorithm, tailored for Brachytherapy in prostate cancer treatment. The primary innovation of the system is the algorithm itself, designed to dynamically adjust needle trajectories in response to the real-time movements of the prostate gland during the local intervention. The system employs real-time position data extracted from Magnetic Resonance Imaging (MRI) to ensure precise targeting of the prostate, adapting to its constant motion and deformation. This precision is crucial in Brachytherapy, where the accurate placement of radioactive seeds directly impacts the efficacy of the treatment and minimizes damage to surrounding safe tissues. Our results demonstrate a marked improvement in the accuracy of radiation seed placement, directly correlating to more effective radiation delivery. The adaptive nature of the algorithm significantly reduces the number of needle insertions, leading to a less invasive treatment experience for patients. This reduction in needle insertions also contributes to lower risks of infection and shorter recovery times. This novel robotic system, enhanced by the adaptive optimization algorithm, improves the coverage of targets reached by a traditional combinatorial approach by approximately 15% with fewer required needles. The improved precision and reduced invasiveness highlight the potential of this system to enhance the overall effectiveness and patient experience in prostate cancer Brachytherapy.

Comparison of perioperative and subacute postoperative complications between LDR and HDR monotherapy brachytherapy for prostate cancer

We aim to investigate perioperative and subacute postoperative complications in patients undergoing LDR or HDR monotherapy for prostate cancer. We hypothesize a low rate of complications, and a favorable toxicity profile in patients treated with HDR compared to LDR. A prospectively collected institutional database was queried for patients treated with HDR or LDR prostate monotherapy between 1998 and 2021. Toxicities were determined per CTCAE. Claims based billing codes were obtained to identify additional events. Events occurring within 4 months of treatment were defined as perioperative or subacute postoperative complications. 759 patients were identified, 446 received LDR with 125I, and 313 received HDR with 192Ir. HDR patients had higher risk features: 75.7% with Gleason score 7+ versus 2.4% of LDR, and 16% with initial PSA 10+ ng/mL versus 2.7% of LDR. Toxicities were mild with the most common being grade 1 GU frequency and nocturia at ∼50%. HDR patients had significantly less grade 2 dysuria (2.6% vs. 9.0%), frequency (4.8% vs. 9.4%), hematuria (1.0% vs. 5.2%), nocturia (3.8% vs. 9.4%), and urinary obstructive symptoms (7.3% vs. 11.2%), all statistically significant. 11 (1.4%) patients had infection requiring antibiotics: 8 (1.8%) from the LDR group and 3 (1%) from the HDR group. Cardiopulmonary events were low at <2% overall, without difference between HDR and LDR. Overall toxicity rates support the safety of prostate brachytherapy. HDR monotherapy is associated with significantly less perioperative and subacute postoperative GU events when compared to LDR monotherapy. Cardiopulmonary events were equally rare in both groups.

Salvage low-dose-rate brachytherapy for locally recurrent prostate cancer after definitive irradiation

PurposeThe optimal management of locally recurrent prostate cancer after definitive irradiation is still unclear but local salvage treatments are gaining interest. A retrospective, single-institution analysis of clinical outcomes and treatment-related toxicity after salvage I-125 low-dose-rate (LDR) brachytherapy (BT) for locally-recurrent prostate cancer was conducted in a Comprehensive Cancer Center. Patients and methodsA total of 94 patients treated with salvage LDR-BT between 2006 and 2021 were included. The target volume was either the whole-gland +/- a boost on the GTV, the hemigland, or only the GTV. The prescribed dose ranged from 90 to 145 Gy. Toxicity was graded by Common Terminology Criteria for Adverse Events (CTCAE) v5.0. ResultsMedian follow-up was 34 months. Initial radiotherapy was external beam radiotherapy in 73 patients (78 %) with a median dose of 76 Gy and I-125 BT in 21 patients (22 %) with a prescribed dose of 145 Gy. Median PSA at salvage was 3.75 ng/ml with a median interval between first and salvage irradiation of 9.4 years. Salvage brachytherapy was associated with androgen deprivation therapy for 32 % of the patients. Only 4 % of the patients were castrate-resistant. Failure free survival was 82 % at 2 years and 66 % at 3 years. The only factors associated with failure-free survival on multivariate analysis were hormonosensitivity at relapse and European Association of Urology (EAU) prognostic group. Late grade 3 urinary and rectal toxicities occurred in 12 % and 1 % of the patients respectively.No significant difference in toxicity or efficacy was observed between the three implant volume groups. ConclusionThe efficacy and toxicity results are consistent with those in the LDR group of the MASTER meta-analysis. Salvage BT confirms to be an effective and safe option for locally recurrent prostate cancer. A focal approach could be interesting to reduce late severe toxicities, especially urinary.

Effect of Polyacrylamide-Based Rectal Gel Spacers on Dose Distribution and Rectal Toxicity during High-Dose-Rate Brachytherapy for Prostate Cancer

Effect of Polyacrylamide-Based Rectal Gel Spacers on Dose Distribution and Rectal Toxicity during High-Dose-Rate Brachytherapy for Prostate Cancer

Fully Distributed Shape Sensing of a Flexible Surgical Needle Using Optical Frequency Domain Reflectometry for Prostate Interventions.

In minimally invasive procedures such as biopsies and prostate cancer brachytherapy, accurate needle placement remains challenging due to limitations in current tracking methods related to interference, reliability, resolution or image contrast. This often leads to frequent needle adjustments and reinsertions. To address these shortcomings, we introduce an optimized needle shape-sensing method using a fully distributed grating-based sensor. The proposed method uses simple trigonometric and geometric modeling of the fiber using optical frequency domain reflectometry (OFDR), without requiring prior knowledge of tissue properties or needle deflection shape and amplitude. Our optimization process includes a reproducible calibration process and a novel tip curvature compensation method. We validate our approach through experiments in artificial isotropic and inhomogeneous animal tissues, establishing ground truth using 3D stereo vision and cone beam computed tomography (CBCT) acquisitions, respectively. Our results yield an average RMSE ranging from 0.58 ± 0.21 mm to 0.66 ± 0.20 mm depending on the chosen spatial resolution, achieving the submillimeter accuracy required for interventional procedures.

557: Local salvage brachytherapy for recurrent prostate cancer: a mono-institutional experience.

557: Local salvage brachytherapy for recurrent prostate cancer: a mono-institutional experience.

1069: Prospective trial with hemiglandular brachytherapy in low-risk prostate cancer: a negative study.

1069: Prospective trial with hemiglandular brachytherapy in low-risk prostate cancer: a negative study.

690: Brachytherapy for favorable prostate cancer in men up to 60 years of age: long term follow up

690: Brachytherapy for favorable prostate cancer in men up to 60 years of age: long term follow up

559: PSA outcomes after LDR/HDR brachytherapy in LR and IR prostate cancer: a predictor of response

559: PSA outcomes after LDR/HDR brachytherapy in LR and IR prostate cancer: a predictor of response

Brachytherapy for favorable prognostic prostate cancer in men up to 60 years of age: Long term follow-up

Brachytherapy (BT) is a standard treatment for low- and favorable intermediate-risk prostate adenocarcinoma. Few studies have focused on young patients. We therefore evaluated long-term efficacy and toxicity of BT in patients aged ≤ 60 years with low- and favorable intermediate-risk prostate cancer. This retrospective study included patients aged ≤60 years with low- or favorable intermediate-risk prostate adenocarcinoma treated with iodine BT alone between 1999 and 2014 at the Institut de Cancérologie de Lorraine. Follow-up assessment included incidence of biochemical failure (BF) at 10 and 15 years after BT, as well as survival data and late toxicities. A total of 177 patients of median age 56 years (54-58) were analyzed, with a median follow-up of 126 months (97-172). Incidence of BF at 10 and 15 years after BT was 5.4% and 11.7% respectively. PSA nadir (HR = 51.8 [95% CI 6.69-277], p < 0.001), age at treatment (HR = 1.78 [95% CI 1.19-2.65], p = 0.005) and prostate D90% (HR = 1.08 [95% CI 1.01-1.15], p < 0.021) were identified as predictive factors of BF. Overall survival at 10 and 15 years after BT was 92.8% and 84.4% respectively. Cancer-specific survival at 10 and 15 years after BT was 99.3% and 97.7% respectively. No major toxicity was recorded. Exclusive BT is a long-term effective treatment for patients aged ≤ 60 years with low- or favorable intermediate-risk prostate adenocarcinoma.