In urban to peri-urban watersheds such as those surrounding San Francisco Bay, stormwater runoff is a major pathway by which contaminants enter aquatic ecosystems. We evaluated the occurrence of 154 organic contaminants liquid chromatography coupled to tandem mass spectrometry, including organophosphate esters (OPEs), bisphenols, per- and polyfluoroalkyl substances (PFASs), and a suite of novel urban stormwater tracers (SWCECs; , vehicle-derived chemicals, pesticides, pharmaceuticals/personal care products, benzothiazoles/benzotriazoles). Time-averaged composite sampling focused on storms in highly developed watersheds over four wet seasons, with complementary sampling in less-urban reference watersheds, near-shore estuarine sites, and the open Bay.
View Article and Find Full Text PDFPurpose: To validate the association between body composition and mortality in men treated with radiation for localized prostate cancer (PCa). Secondarily, to integrate body composition as a factor to classify patients by risk of all-cause mortality.
Materials And Methods: Participants of NRG/Radiation Therapy Oncology Group (RTOG) 9406 and NRG/RTOG 0126 with archived computed tomography were included.
Background: Patients with prostate cancer undergoing treatment with radical radiation therapy (RT) plus androgen deprivation therapy (ADT) experience a constellation of deleterious metabolic and anthropometric changes related to hypogonadism that are associated with increased morbidity and mortality. We assessed the effect of metformin versus placebo to blunt the adverse effects of ADT on body weight, waist circumference, and other metabolic parameters.
Methods And Materials: This phase 2, multicenter, randomized controlled trial (RCT) randomized normoglycemic men with locally advanced prostate cancer receiving radical RT and ADT (18-36 months) in a 1:1 ratio to receive metformin 500 mg by mouth 3 times a day (for 30-36 months) versus identical placebo.
Purpose: In this study, we report the 24-month patient-reported outcomes of the randomized phase 2 CHIRP trial that compared conventional and hypofractionated radiation therapy (RT) in the treatment of high-risk prostate cancer.
Methods And Materials: Men with high-risk localized prostate cancer were randomized to either conventional (78 Gy/39 fractions) or hypofractionated RT (68 Gy/25 fractions). All patients received pelvic nodal RT and adjuvant androgen deprivation therapy.
Androgen deprivation therapy (ADT) used for prostate cancer (PCa) management is associated with metabolic and anthropometric toxicity. Metformin given concurrent to ADT is hypothesized to counteract these changes. This planned interim analysis reports the gastrointestinal and genitourinary toxicity profiles of PCa patients receiving ADT and prostate/pelvic radiotherapy plus metformin versus placebo as part of a phase 2 randomized controlled trial.
View Article and Find Full Text PDFInt J Radiat Oncol Biol Phys
February 2022
Purpose: For men with localized prostate cancer, NRG Oncology/Radiation Therapy Oncology Group (RTOG) 9408 demonstrated that adding short-term androgen deprivation therapy (ADT) to radiation therapy (RT) improved the primary endpoint of overall survival (OS) and improved disease-specific mortality (DSM), biochemical failure (BF), local progression, and freedom from distant metastases (DM). This study was performed to determine whether the short-term ADT continued to improve OS, DSM, BF, and freedom from DM with longer follow-up.
Methods And Materials: From 1994 to 2001, NRG/RTOG 9408 randomized 2028 men from 212 North American institutions with T1b-T2b, N0 prostate adenocarcinoma and prostate-specific antigen (PSA) ≤20ng/mL to RT alone or RT plus short-term ADT.
Purpose: Hypofractionated radiation therapy (HFRT) may offer treatment advantages for patients with prostate cancer. However, HFRT may also increase the risk of gastrointestinal (GI) or genitourinary (GU) toxicity compared with conventionally fractionated radiation therapy (CFRT). Several large trials have found that HFRT is well tolerated in mixed risk population studies.
View Article and Find Full Text PDFChanges in the field of radiation oncology (RO) impacts residency training. Assessing trainee experiences is essential to inform curriculum development. We aim to explore gaps and strengths in current Canadian RO training, as we move towards competency-based medical education (CBME).
View Article and Find Full Text PDFPrior Pan-Canadian surveys of Radiation Oncology (RO) residents reveal a decrease in Canadian RO employment opportunities. Canadian RO resident levels increased from 130 in 2003, peaked at 209 in 2009, then decreased to 130 in 2017. Recognizing that RO has entered another period of transition, we re-examined resident motivations and perspectives on the job market and explored well-being and career aspirations among a contemporary cohort of Canadian RO residents.
View Article and Find Full Text PDFBackground: Prophylactic cranial irradiation (PCI) improves survival and prevents intracranial recurrence (IR) in limited stage (LS) and extensive stage (ES) small cell lung cancer (SCLC). However, despite PCI, IR affects 12%-45%, and limited data exist regarding salvage brain reirradiation (ReRT). We performed a population-based review of IR in SCLC.
View Article and Find Full Text PDFSupport Care Cancer
April 2020
Purpose: Many patients with advanced cancer receive primary supports from informal caregivers (IC). As patient health deteriorates, IC assume increasing responsibility, often accompanied by distress. We investigated the quality of life (QOL) of IC of patients referred to a palliative radiotherapy (PRT) program.
View Article and Find Full Text PDFPurpose: To report results of an initial pilot study assessing iodine-125 prostate implant treatment plans created automatically by a new seed-placement method.
Methods And Materials: A novel mixed-integer linear programming method incorporating spatial constraints on seed locations in addition to standard dose-volume constraints was used to place seeds. The approach, described in detail elsewhere, was used to create treatment plans fully automatically on a retrospective basis for 20 patients having a wide range of prostate sizes and shapes.
Purpose: Real-time tracking of lung tumors using magnetic resonance imaging (MRI) has been proposed as a potential strategy to mitigate the ill-effects of breathing motion in radiation therapy. Several autocontouring methods have been evaluated against a "gold standard" of a single human expert user. However, contours drawn by experts have inherent intra- and interobserver variations.
View Article and Find Full Text PDFPurpose: This study was undertaken to determine if significant seed migration occurred when our institution changed seed products by comparing patterns of seed migration in implants containing different stranding material.
Methods And Materials: Day 0 and Day 30 CT scans were registered by the contoured prostate center of mass. An implant reconstruction program identified seeds on CT according to the pre-plan, enabling one-to-one correspondence between Day 0 and Day 30 seeds.
Purpose: The quality of a prostate brachytherapy implant depends on the accurate placement of sources. This study quantifies the misplacement of I sources from the intended location using intraoperative ultrasound images.
Methods And Materials: I sources were manually identified in the postimplant ultrasound images and compared to the preoperative plan.
Purpose: To report on the importance of cancer location from diagnostic prostate biopsies in predicting biochemical relapse for patients treated with (125)I seed implant brachytherapy as monotherapy for favorable risk disease; specifically, to assess the clinical significance of potentially underdosing the base region of the prostate gland.
Methods And Materials: Of 1145 consecutive patients, 846 had pretreatment biopsies allowing for sextant analysis and consequent evaluation of biochemical failure tendencies. Biochemical failure was defined as a posttreatment rise in the nadir prostate-specific antigen (PSA) by at least 2 ng/mL.
Purpose: The purpose of this study was to characterize benign prostate-specific antigen (PSA) bounces of at least 2.0 ng/mL and biochemical failure as defined by the Phoenix definition after prostate brachytherapy at our institution, and to investigate distinguishing features between three outcome groups: patients experiencing a benign PSA bounce, biochemical failure, or neither.
Material And Methods: Five hundred and thirty consecutive men treated with low-dose-rate brachytherapy with follow-up of at least 3 years were divided into outcome groups experiencing bounce, failure, or neither.
Purpose: The local control of inoperable non-small cell lung cancer (NSCLC) using standard radiotherapy (RT) doses is inadequate. Dose escalation is a potential strategy to improve the local control for patients with NSCLC; however, the optimal dose required for local control in this setting is unknown.
Methods And Materials: Patients with unresectable or inoperable stage II/III NSCLC with ECOG≤1 received 48 Gy in 20 daily fractions using intensity-modulated radiotherapy, followed by 1 of 3 boost dose levels: 16.
Objective: To assess late toxicity and outcomes in high-risk prostate cancer patients treated with hypofractionated radiation treatment with androgen suppression therapy.
Methods: Sixty high-risk prostate cancer patients were enrolled. IMRT prescription was 68 Gy/25 fractions (2.
Purpose: To identify clinical, dosimetric, and genetic factors that are associated with late urinary toxicity after a (125)I prostate brachytherapy implant.
Methods And Materials: Genomic DNA from 296 men treated with (125)I prostate brachytherapy monotherapy was extracted from saliva samples for this study. A retrospective database was compiled including clinical, dosimetric, and toxicity data for this cohort of patients.
Brominated diphenyl ethers (BDEs) are flame retardant compounds that have been classified as persistent organic pollutants under the Stockholm Convention and targeted for phase-out. Despite their classification as persistent, PBDEs undergo debromination in the environment, via both microbial and photochemical pathways. We examined concentrations of 24 PBDE congeners in 233 sediment samples from San Francisco Bay using Positive Matrix Factorization (PMF).
View Article and Find Full Text PDFPurpose: To compare the implant quality and clinical outcomes for patients treated with low and intermediate strength (125)I seeds in prostate brachytherapy implants.
Methods And Materials: This retrospective review included 390 consecutive patients treated with prostate brachytherapy from 1999 to 2006. The first 142 patients were implanted with source strengths lower than 0.
Purpose: This study quantified the treatment margin (TM) around the prostate that received 100% of the prescribed dose and analyzed postimplant dosimetry in different regions of the prostate for (125)I seed implants.
Methods And Materials: An average target volume (ATV) was created from postoperative MRI scan contours drawn independently by five radiation oncologists in 40 patients. The MRI was fused with the postoperative CT for dosimetry purposes.
Purpose Of The Study: To survey employment and training characteristics of Canadian radiation oncology training program graduates and foreign medical graduates with Canadian radiation oncology post-graduate education or specialist certification.
Methods: A 38-question, web-based survey was distributed to radiation oncologists who completed specialty training between 2000-2010.
Results: Out of 256 radiation oncologists contacted, 148 completed the survey (58% response rate).
Purpose: To compare preimplant prostate contours and contouring variability between magnetic resonance (MR) and transrectal ultrasound images.
Methods And Materials: Twenty-three patients were imaged using ultrasound (US) and MR before permanent brachytherapy treatment. Images were anonymized, randomized, and duplicated, and the prostate was independently delineated by five radiation oncologists.