Publications by authors named "I-Chow Hsu"

Purpose: The healthcare system is resource intensive, and many opportunities exist to reduce medical waste. Brachytherapists performing inherently resource intensive procedures are well poised to initiate the transition to sustainable, climate-smart care. The authors developed a quality improvement-based (QI) NorCal Brachytherapy Waste Audit Toolkit to guide medical waste reduction in brachytherapy procedures and provide climate health education.

View Article and Find Full Text PDF

Background: Cervical cancer continues to disproportionately affect marginalized populations, with significant disparities in treatment and outcomes. Social determinants of health and insurance status have been associated with delays in treatment initiation, which can adversely affect clinical outcomes.

Objective: To determine the risk factors associated with delays in treatment initiation among patients with locally advanced cervical cancer and identify the time period of delay in treatment initiation.

View Article and Find Full Text PDF

Purpose: Accurate target delineation is essential when using intensity modulated radiation therapy for intact cervical cancer. In 2011, the Radiation Therapy Oncology Group published a consensus guideline using magnetic resonance imaging (MRI). The current project expands on the previous atlas by including computed tomography (CT)-based contours, contours with MRI and positron emission tomography (PET) registrations, the addition of common and complex scenarios, and incorporating information on simulation and treatment planning techniques.

View Article and Find Full Text PDF

Purpose: To develop patient-specific 3D models using Finite-Difference Time-Domain (FDTD) simulations and pre-treatment planning tools for the selective thermal ablation of prostate cancer with interstitial ultrasound. This involves the integration with a FDA 510(k) cleared catheter-based ultrasound interstitial applicators and delivery system.

Methods: A 3D generalized "prostate" model was developed to generate temperature and thermal dose profiles for different applicator operating parameters and anticipated perfusion ranges.

View Article and Find Full Text PDF

Introduction: Inflammatory bowel disease (IBD) is a relative contraindication to external beam radiation therapy (EBRT) for prostate cancer patients due to fear of increased risk of gastrointestinal (GI) toxicity. High-dose-rate (HDR) brachytherapy, capable of minimizing radiation dose to surrounding tissues, is a feasible alternative. Given limited data, this study examined the safety profile of HDR brachytherapy in this setting.

View Article and Find Full Text PDF

Purpose: A history of prior pelvic radiation therapy (RT) for rectal cancer is a relative contraindication for definitive RT for prostate cancer. High-dose-rate (HDR) brachytherapy can significantly limit the dose to surrounding tissues compared to external beam RT. However, there is limited data surrounding its safety in patients with prior pelvic RT.

View Article and Find Full Text PDF

Purpose: The Ocean Road Cancer Institute (ORCI) in Tanzania began offering 3D conformal radiation therapy (3DCRT) in 2018. Steep learning curves, high patient volume, and a limited workforce resulted in long radiation therapy (RT) planning workflows. We aimed to establish the feasibility of implementing an automation-assisted cervical cancer 3DCRT planning system.

View Article and Find Full Text PDF

Background And Purpose: Local recurrences after previous radiotherapy (RT) are increasingly being identified in biochemically recurrent prostate cancer. Salvage prostate brachytherapy (BT) is an effective and well tolerated treatment option. We sought to generate international consensus statements on the use and preferred technical considerations for salvage prostate BT.

View Article and Find Full Text PDF

Purpose: This study aims to evaluate the outcomes and toxicities in patients with palpable local recurrence of prostate cancer after radical prostatectomy (RP), who were treated with salvage high dose-rate brachytherapy (HDR-BT) with or without pelvic external beam radiotherapy (EBRT).

Methods: This retrospective review included patients with palpable local recurrence of prostate cancer after RP who underwent salvage HDR-BT at a single institution between 2002 and 2020. HDR-BT regimens included 950 cGy x 2 (N = 4) or 1500 cGy x 1 (N = 2) combined with EBRT; or monotherapy with 950 cGy x 4 (N = 1) or 800 cGy x 2 (N = 1).

View Article and Find Full Text PDF

Objective: We sought to evaluate whether the survival benefit of adjuvant radiotherapy in patients with node-positive vulvar cancer is maintained in older patients, who comprise a large subgroup of patients with vulvar cancer.

Methods: The National Cancer Database (NCDB) was queried for patients aged 65 years or older, who were diagnosed with vulvar squamous cell carcinoma from 2004 to 2017 and underwent surgery with confirmed node-positive disease. Statistical analysis was performed with propensity-score matching, chi-square test, log-rank test, Kaplan-Meier, and multivariable Cox proportional regression.

View Article and Find Full Text PDF

Purpose: Inverse planning simulated annealing (IPSA) produces highly conformal dose distributions and quick optimizations for high-dose-rate interstitial brachytherapy (HDRBT). We report our dosimetry and overall outcomes using this approach for the accelerated post-operative treatment of pathologically node-negative squamous cell carcinomas of the oral tongue (OTSCC) with high risk of local recurrence.

Methods: Patients with newly diagnosed pN0 OTSCC treated with partial glossectomy, neck dissection, and post-operative HDRBT alone from 2007 to 2021 were retrospectively reviewed.

View Article and Find Full Text PDF

Purpose: Side effect profiles play an important role in treatment decisions for localized prostate cancer. Emergency department (ED) visits, which may be due to side effects from treatment, can be measured in real-world, structured, electronic health record (EHR) data. The goal of this study was to determine whether treatments for localized prostate cancer are associated with ED visits, as a measure of side effects, using EHR data.

View Article and Find Full Text PDF

Ultrasound can provide real-time imagery without the risk of radiation exposure, and it is widely available at a relatively low cost. It can provide updated three-dimensional information that can improve the physician's spatial awareness during a brachytherapy procedure for cervical cancer. There is mounting evidence demonstrating the numerous benefits of ultrasound-guided brachytherapy in the published literature.

View Article and Find Full Text PDF

Purpose: Nasopharyngeal brachytherapy is limited in part by the radiotolerance of nearby organs like the soft palate. This study explores several novel shielding designs for an intracavitary applicator to significantly reduce soft palate dose while adhering to the constraints of standard treatment procedure.

Methods: The Monte Carlo code TOPAS is used to characterize each prototype under typical high-dose-rate treatment conditions.

View Article and Find Full Text PDF

Background: To evaluate acute and late genitourinary and gastrointestinal toxicities and patient reported urinary and sexual function following accelerated, hypofractionated external beam radiotherapy to the prostate, seminal vesicles and pelvic lymph nodes and high dose rate (HDR) brachytherapy or stereotactic body radiation therapy (SBRT) prostate boost.

Methods: Patients at a single institution with NCCN intermediate- and high-risk localized prostate cancer with logistical barriers to completing five weeks of whole pelvic radiotherapy (WPRT) were retrospectively reviewed for toxicity following accelerated, hypofractionated WPRT (41.25 Gy in 15 fractions of 2.

View Article and Find Full Text PDF

The inverse planning simulated annealing optimization engine was used to develop a new method of incorporating biological parameters into radiation treatment planning. This method integrates optimization of a radiation schedule over multiple types of delivery methods into a single algorithm. We demonstrate a general procedure of incorporating a functional biological dose model into the calculation of physical dose prescriptions.

View Article and Find Full Text PDF

Purpose: Bulky chest wall recurrence after mastectomy presents a therapeutic challenge because of high-dose of radiation required to control the disease, and its proximity to low-tolerance organs at risk. We report a case of successful computed tomography (CT)-guided high-dose-rate (HDR) salvage interstitial brachytherapy (ISBT) boost.

Material And Methods: A 70-year-old female initially presented with a tumor in right breast, and was treated with mastectomy and adjuvant chemotherapy, followed by hormonal therapy for 5 years without adjuvant radiotherapy.

View Article and Find Full Text PDF

Purpose: Salvage high-dose-rate brachytherapy (sHDRBT) for locally recurrent prostate cancer after definitive radiation is associated with biochemical control in approximately half of patients at 3 to 5 years. Given potential toxicity, patient selection is critical. We present our institutional experience with sHDRBT and validate a recursive partitioning machines model for biochemical control.

View Article and Find Full Text PDF

Purpose: This is a report of our initial experience using computed tomography (CT)-guided interstitial high dose rate (HDR) brachytherapy to treat bulky pelvic nodal metastases as a part of definitive radiotherapy.

Material And Methods: Between February 2015 and April 2019, 14 cervical/endometrial cancer patients presenting with bulky pelvic node(s) underwent nodal interstitial brachytherapy boost in our institution. In total, 17 nodes were treated.

View Article and Find Full Text PDF
Article Synopsis
  • The study focuses on the outcomes of women with vaginal recurrences of endometrial cancer who underwent reirradiation, specifically using image-guided interstitial high-dose-rate (HDR) brachytherapy after previous treatments.
  • Twenty-three women were analyzed, revealing a median time of 13.7 months since their initial radiation therapy, with various outcomes including an overall survival rate of 56% and local control rate of 87%.
  • The findings suggest that while the reirradiation technique has a good local control rate and manageable toxicity, distant recurrences remain a significant challenge, indicating further research is necessary to optimize treatment strategies.
View Article and Find Full Text PDF

Purpose: To perform a propensity-score matched analysis comparing stereotactic body radiation therapy (SBRT) boost and high-dose-rate (HDR) boost for localized prostate cancer.

Methods And Materials: A single-institution retrospective chart review was conducted of men treated with pelvic external beam radiation therapy (EBRT) and SBRT boost (21 Gy and 19 Gy in 2 fractions) to the prostate for prostate cancer. A cohort treated at the same institution with HDR brachytherapy boost (19 Gy in 2 fractions) was compared.

View Article and Find Full Text PDF

Purpose: To report the long-term outcome of patients with prostate cancer treated with external beam radiation therapy and high dose rate (HDR) brachytherapy from a prospective multi-institutional trial conducted by NRG Oncology/RTOG.

Methods And Materials: Patients with clinically localized (T1c-T3b) prostate cancer without prior history of transurethral resection of prostate or hip prosthesis were eligible for this study. All patients were treated with a combination of 45 Gy in 25 fractions from external beam radiation therapy and one HDR implant delivering 19 Gy in 2 fractions.

View Article and Find Full Text PDF

Objective: Although multimodality therapy has been shown to improve outcomes for patients with high-risk endometrial carcinoma, optimal type and timing of adjuvant therapies is unknown.

Methods: Patients with stage I-IVA endometrial carcinoma diagnosed from 2004 to 2015, and treated with surgery, chemotherapy, and radiation were identified in the National Cancer Database. Adjuvant treatment was categorized as sequential radiation followed by chemotherapy (RT-CT), concurrent chemoradiation (CCRT, RT and CT started within 7 days), or sequential chemotherapy followed by radiation (CT-RT).

View Article and Find Full Text PDF

Purpose: We aimed to examine utilization patterns of positron emission tomography scans (PET or PET/CT) beyond 6 months after cervical cancer treatment. We investigated survival outcomes of asymptomatic patients with PET-detected recurrence.

Methods: We performed a retrospective review of 283 patients with stage IA-IVA cervical cancer treated with primary chemoradiation.

View Article and Find Full Text PDF

A PHP Error was encountered

Severity: Warning

Message: fopen(/var/lib/php/sessions/ci_sessionkt58fjlqn192vsepegtmetjhcjoiubvd): Failed to open stream: No space left on device

Filename: drivers/Session_files_driver.php

Line Number: 177

Backtrace:

File: /var/www/html/index.php
Line: 316
Function: require_once

A PHP Error was encountered

Severity: Warning

Message: session_start(): Failed to read session data: user (path: /var/lib/php/sessions)

Filename: Session/Session.php

Line Number: 137

Backtrace:

File: /var/www/html/index.php
Line: 316
Function: require_once