Publications by authors named "Aldrich Ong"

Article Synopsis
  • A clinical trial called RADICALS-HD studied the effects of adding short-course androgen deprivation therapy (ADT) to postoperative radiotherapy in patients with localized prostate cancer after surgery.
  • It involved 1480 patients, examining how ADT impacts metastasis-free survival compared to radiotherapy alone, and measured outcomes like distant metastasis and overall survival.
  • The trial aimed to see if combining ADT with radiotherapy could improve the 10-year metastasis-free survival rate, potentially increasing it from 80% to 86%.
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Article Synopsis
  • The study investigates the effectiveness and optimal duration of androgen deprivation therapy (ADT) combined with postoperative radiotherapy for patients with localized prostate cancer following radical prostatectomy.
  • A randomised controlled trial, RADICALS-HD, compared short-course ADT (6 months) to long-course ADT (24 months) among participants who met specific criteria, including PSA levels and absence of metastatic disease.
  • The primary outcome measured was metastasis-free survival, with the trial aiming to determine if longer ADT duration leads to better survival rates, involving over 1,500 patients from 2008 to 2015.
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Background: Radiation therapy (RT) is an established palliative treatment for bone metastases; however, little is known about post-radiation survival and factors which impact it. The aim of this study was to assess a population-based sample of metastatic prostate cancer patients receiving palliative radiation therapy to bone metastases and contemporary palliative systemic therapy and identify factors that impact long-term survival.

Materials/methods: This retrospective, population-based, cohort study assessed all prostate cancer patients receiving palliative RT for bone metastases at a Canadian provincial Cancer program during a contemporary time period.

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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.

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In early 2017, the Canadian Partnership Against Cancer and CancerCare Manitoba undertook a comprehensive knowledge translation (KT) campaign to improve the utilization of single fraction radiotherapy (SFRT) over multiple fraction radiotherapy (MFRT) for palliative management of bone metastases. The campaign significantly increased short-term SFRT utilization. We assess the time-dependent effects of KT-derived SFRT utilization 12-24 months removed from the KT campaign in a Provincial Cancer Program.

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Objective: Our study aimed to analyze recurrence and survival outcomes in stage II endometrial cancer patients treated with adjuvant radiotherapy at CancerCare Manitoba, a Canadian provincial cancer program.

Methods: This retrospective population-based cohort study identified all International Federation of Gynecology and Obstetrics (FIGO) 2009 stage II endometrioid type endometrial carcinoma diagnosed between January 1995 and December 2019. All patients underwent surgery followed by vaginal vault brachytherapy alone or external beam pelvic radiotherapy plus vaginal vault brachytherapy.

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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.

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Aims: Aldosterone has been found to influence cancer cell growth, cell cycle regulation and cell migration, including in prostate cancer cells. Spironolactone is an aldosterone antagonist used for managing chronic heart failure (HF) with known antiandrogenic effects. We examined the effect of spironolactone exposure amongst men with HF on the incidence of prostate cancer.

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Objectives: Androgen deprivation therapy (ADT) is the standard of care for men with nonmetastatic hormone-sensitive prostate cancer (nmHSPC) after treatment failure. Although intermittent ADT (iADT) is noninferior to continuous ADT for prostate cancer outcomes, with superior quality of life and cost-to-benefit ratio, little is known regarding its real-world utilization. The authors aimed to determine the utilization of iADT in a Canadian Provincial Cancer Program for relapsed nmHSPC and identified risk factors associated with the nonreceipt of iADT.

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Purpose: Although level 1 evidence supports the use of single-fraction radiation therapy (SFRT) compared with multiple-fraction radiation therapy (MFRT) for the palliative management of bone metastases, SFRT is underused. In early 2017, the Canadian Partnership Against Cancer and CancerCare Manitoba undertook a comprehensive knowledge translation campaign in Manitoba, Canada featuring educational outreach visits, local consensus meetings, and audit and feedback interventions to encourage greater use of SFRT. This study assessed the impact of this campaign on SFRT use and identified variables associated with MFRT usage.

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Background: Prostate stereotactic ablative radiotherapy (SABR) regimens differ in time, dose, and fractionation. We report an update of a multicentre, Canadian randomized phase II study to investigate the impact of overall treatment time on quality of life (QOL), efficacy, and toxicity.

Methods: Men with intermediate risk prostate cancer were randomized to 40 Gy in 5 fractions delivered every other day (EOD) versus once per week (QW).

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Purpose: SABR offers an effective treatment option for clinically localized prostate cancer. Here we report the dosimetric predictors of late toxicity and quality of life (QOL) in a pooled cohort of patients from four phase II trials.

Methods: The combined cohort included all three prostate cancer risk groups.

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Patient-specific assessment, disease monitoring, and the development of an accurate early surrogate of the therapeutic efficacy of locally advanced prostate cancer still remain a clinical challenge. Contrary to prostate biopsies, circulating tumor cell (CTC) collection from blood is a less-invasive method and has potential as a real-time liquid biopsy and as a surrogate marker for treatment efficacy. In this study, we used size-based filtration to isolate CTCs from the blood of 100 prostate cancer patients with high-risk localized disease.

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Purpose: Stereotactic ablative radiotherapy (SABR) is appealing for prostate cancer (PCa) due to low α/β, and increasing the dose per fraction could improve the therapeutic index and lead to a better quality of life (QOL). Here we report the outcomes of a QOL comparison between two phase II clinical trials: two vs. five fraction prostate SABR.

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Background And Purpose: Prostate stereotactic body radiotherapy (SBRT) regimens differ in time, dose, and fractionation. We completed a multicentre, randomized phase II study to investigate the impact of overall treatment time on quality of life (QOL).

Material And Methods: Men with low and intermediate-risk prostate cancer were randomly assigned to 40 Gy in 5 fractions delivered once per week (QW) vs.

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Context Daily variations in bladder size and position can negatively impact the ability to accurately deliver radiation. Aims We attempted to quantify how bladder volumes and positions change over the course of radiotherapy for muscle invasive bladder cancer and the planning target volume (PTV) margins required to account for such changes. Methods and material Cone-beam computed tomography (CT) images of 28 patients during their first, second, and third fractions and weekly thereafter were acquired.

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Introduction: To examine the impact of published randomized controlled trial (RCT) data on referrals for adjuvant radiotherapy (RT) in patients who had high-risk pathologic features after radical prostatectomy (RP).

Methods: In this population-based, retrospective Canadian study, all patients who received a diagnosis of prostate adenocarcinoma and underwent RP from 2003-2008 were identified through the Manitoba Cancer Registry. Manual review of pathology reports was performed, and patients who had high-risk pathologic features of extracapsular extension, seminal vesicle invasion, or positive surgical margins were included.

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Purpose: To investigate the dosimetric outcome of brachytherapy in patients with small prostate volume (PV).

Methods And Materials: Forty-three patients with small PV (<25 cm(3)) as determined using transrectal ultrasound and 120 patients with non-small PV (>25 cm(3)) that had received (125)I seed implants were reviewed in a retrospective cohort study. Implantations were performed under transrectal ultrasound guidance, and the prescription dose was 145 Gy.

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Synopsis of recent research by authors named "Aldrich Ong"

  • - Aldrich Ong's recent research primarily focuses on the role and optimization of androgen deprivation therapy (ADT) combined with radiotherapy for prostate cancer, exploring the efficacy of both short-course and long-course ADT in postoperative settings based on randomized controlled trials.
  • - His studies also investigate the long-term survival factors after palliative radiotherapy for bone metastasis in prostate cancer patients, emphasizing the patient population's characteristics and treatment outcomes.
  • - Additionally, Ong has conducted trials assessing the metabolic side effects of ADT, evaluating the potential benefits of metformin to mitigate these issues and examining the impact of coordinated knowledge translation campaigns on the utilization of single-fraction radiotherapy for better patient care outcomes.