Variation in Access to Palliative Radiotherapy in Prostate Cancer: A Population-Based Study in Canada.

BACKGROUND: As a result of improvements in cancer therapies, patients with metastatic malignancies are living longer, and the role of palliative radiotherapy has become increasingly recognized. However, access to adequate palliative radiotherapy may continue to be a challenge, as is evident from the high proportion of patients dying of prostate cancer who never receive palliative radiotherapy. The main objective of this investigation is to identify and describe the factors associated with the receipt of palliative radiation treatment in a decedent cohort of prostate cancer patients in Ontario. METHODOLOGY:  Population-based administrative databases from Ontario, Canada, were used to identify prostate cancer decedents, 65 years or older who received androgen deprivation therapy between January 1, 2013, and December 31, 2018. Baseline and treatment characteristics were analyzed using univariate and multivariate logistic regression models for association with receipt of radiotherapy in a two-year observation period before death. RESULTS: We identified 3,788 prostate cancer decedents between 2013 and 2018; among these, 49.9% received radiotherapy in the two years preceding death. There were statistically significant positive associations between receipt of radiotherapy and younger age at diagnosis (odds ratio [OR] 1.6, 95% confidence interval [CI] 1.1-2.3); higher stage at diagnosis (OR 1.3, 95% CI 1.1-1.7); receipt of care at a regional cancer center (OR 1.8, 95% CI 1.3-2.4); and involvement of radiation oncologists (OR 155.1, 95% CI 83.3-288.7) or medical oncologists (OR 1.4, 95% CI 1.1-1.8). However, there were no associations between receipt of radiotherapy and income, distance to the nearest cancer center, involvement of urologists in cancer care, healthcare administrative region, home-care involvement, or number of hospitalizations in the observation period. CONCLUSIONS: We found the utilization of palliative radiotherapy for prostate cancer patients in Ontario varies depending on age, stage at diagnosis, number of comorbidities, registration at regional cancer centers, and involvement of oncologists. There were no differences detected based on income or distance from a cancer center. The findings of this study represent an important opportunity to facilitate better access to palliative radiotherapy and referrals to multidisciplinary regional cancer centers, to improve the quality of life of this patient population.

Real-World Evaluation of Primary Versus Secondary Prevention of Skeletal-Related Events in Metastatic Castration-Resistant Prostate Cancer.

INTRODUCTION: Anti-osteoclast treatment with denosumab or zoledronate is known to effectively reduce the need for radiotherapy to bone and other skeletal-related events (SREs) in patients with metastatic castration-resistant prostate cancer (mCRPC). In this study, we analyze primary versus secondary initiation of bone-targeting agents (BTAs) relative to first palliative bone radiotherapy in patients dying of mCRPC. METHODS: Provincial administrative databases from Ontario, Canada identified patients with prostate cancer (2007-2018, n = 98 646) who received continuous androgen deprivation therapy (n = 29 453), died of prostate cancer (2013-2018, n = 3864), and received life-prolonging therapy for mCRPC (n = 1850). Variables were collected looking back 3 years from death. Multivariable analysis explored the relationship between clinical variables and BTAs. RESULTS: Of the 58% (1066/1850) patients with mCRPC who received BTA, only 289 (25.4%) started BTA prior to first palliative bone radiotherapy as primary prevention. Eight hundred and forty-eight (74.6%) patients either never received BTA before death (n = 447) or started BTA only after first bone radiotherapy (n = 401). More patients received denosumab (n = 825, 77%) than zoledronic acid (n = 241, 23%). 51.2% (582/1137) of palliative bone radiotherapy was initiated in the last 12 months of life. Factors associated with the use of BTA included elevated alkaline phosphatase (OR = 1.0, P = .023), de novo metastases (OR = 1.4, P = .005), medical oncologist involvement (OR = 2.0, P = .007), diagnosis 2012-2017 versus 2007-2011 (OR = 0.75, P = .034), and academic center (OR = 0.061, P = .007). CONCLUSION: A majority of patients with mCRPC never receive BTAs prior to first SRE, despite universal access and availability of these agents in Ontario. These results highlight an opportunity to improve outcomes by emphasizing early introduction of BTA in patients with mCRPC being started on systemic therapy.

Cryptogenic Hypervirulent Klebsiella pneumoniae Pyogenic Liver Abscess: A Case Report.

BACKGROUND Klebsiella pneumoniae is a gram-negative organism known to cause pyogenic liver abscesses. It is most often caused by one of the hypervirulent strains, which are capable of causing metastatic infection. This occurs most commonly in Asia in patients without hepatobiliary disease; however, it is becoming increasingly recognized in North America. CASE REPORT We report a previously healthy man in his 50s who presented to hospital with 3 weeks of fever, chills, and mild abdominal pain following a minor motor vehicle collision. Ultrasound and computed tomography of his abdomen revealed a large multi-loculated liver abscess. This was drained percutaneously and grew a hypervirulent strain of Klebsiella pneumoniae known to cause metastatic infection. His blood cultures were negative. In addition to percutaneous drainage, he was treated with 8 weeks of antimicrobial therapy. Fortunately, he did not develop evidence of metastatic infection despite the hypervirulent strain. Etiology of the abscess was not clearly identified; however, it was speculated that the motor vehicle collision could have led to its development through gut translocation. CONCLUSIONS Presentation of Klebsiella pneumoniae liver abscesses is often nonspecific, and clinicians must have a high index of suspicion in order to ensure rapid diagnosis and treatment. Delay in diagnosis is associated with increased morbidity and mortality, and thus it is an important entity for clinicians to be aware of, especially as it becomes more prevalent in North American populations. Additionally, it is important that physicians are aware of the hypervirulent strains and screen patients clinically for evidence of metastatic infection.

A population-based study of factors associated with systemic treatment in advanced prostate cancer decedents.

INTRODUCTION: Life-prolonging therapies (LPTs) are rapidly evolving for the treatment of advanced prostate cancer, although factors associated with real-world uptake are not well characterized. METHODS: In this cohort of prostate-cancer decedents, we analyzed factors associated with LPT access. Population-level databases from Ontario, Canada identified patients 65 years or older with prostate cancer receiving androgen deprivation therapy and who died of prostate cancer between 2013 and 2017. Univariate and multivariable analyses assessed the association between baseline characteristics and receipt of LPT in the 2 years prior to death. RESULTS: Of 3575 patients who died of prostate cancer, 40.4% (n = 1443) received LPT, which comprised abiraterone (66.3%), docetaxel (50.3%), enzalutamide (17.2%), radium-223 (10.0%), and/or cabazitaxel (3.5%). Use of LPT increased by year of death (2013: 22.7%, 2014: 31.8%, 2015: 41.8%, 2016: 49.1%, and 2017: 57.9%, p < 0.0001), driven by uptake of all agents except docetaxel. Adjusted odds of use were higher for patients seen at Regional Cancer Centers (OR: 1.8, 95% CI: 1.5-2.1) and who received prior prostate-directed therapy (OR: 1.3, 95% CI: 1.0-1.5), but lower with advanced age (≥85: OR: 0.54, 95% CI:0.39-0.75), increased chronic conditions (≥6: OR: 0.62, 95% CI: 0.43-0.92), and long-term care residency (OR: 0.38, 95% CI: 0.17-0.89). Income, stage at presentation, and distance to the cancer center were not associated with LPT uptake. CONCLUSION: In this cohort of prostate cancer-decedents, real-world uptake of novel prostate cancer therapies occurred at substantially higher rates for patients receiving care at Regional Cancer Centers, reinforcing the potential benefits for treatment access for patients referred to specialist centers.

Streptococcus agalactiae infective endocarditis in Canada: a multicenter retrospective nested case control analysis.

BACKGROUND: Infective endocarditis (IE) caused by Streptococcus agalactiae (GBS) is increasingly reported and associated with an aggressive course and high mortality rate. Existing literature on GBS IE is limited to case series; we compared the characteristics of patients with GBS IE to patients with GBS bacteremia without IE to identify risk factors for development of IE. METHODS: A nested case-control study in a cohort of adult patients with GBS bacteremia over a 18-year period was conducted across seven centres in three Canadian cities. A chart review identified patients with possible or definite IE (per Modified Duke Criteria) and patients with IE were matched to those without endocarditis in a 1:3 fashion. Multivariate analyses were completed using logistic regression. RESULTS: Of 520 patients with GBS bacteremia, 28 cases of possible or definite IE were identified (5.4%). 68% (19/28) met criteria for definite IE, surgery was performed in 29% (8/28), and the overall in-hospital mortality rate was 29% (8/28). Multivariate analysis demonstrated that IE was associated with injection drug use (OR = 19.6, 95% CI = 3.39-111.11, p = 0.001), prosthetic valve (OR = 11.5, 95% CI = 1.73-76.92, p = 0.011) and lack of identified source of bacteremia (OR = 3.81, 95% CI = 1.24-11.65, p = 0.019). CONCLUSIONS: GBS bacteremia, especially amongst people who inject drugs, those with prosthetic valves, and those with no apparent source of infection, should increase clinical suspicion for IE.

Evaluating the endometabolic and bone health effects of Tyrosine Kinase Inhibitors in Chronic Myeloid Leukaemia: a systematic review protocol.

INTRODUCTION: Chronic Myeloid Leukaemia (CML) constitutes 15% of new adult leukaemia cases as well as 2%-3% of leukaemia in children under 15% and 9% of leukaemias in adolescents 15-19 years of age annually. The introduction of Tyrosine Kinase Inhibitors (TKI) therapy has dramatically improved survival in these patients, yet the off-target effects of this treatment may have long-term health impacts on CML survivors. The risk of adverse health outcomes is especially important in children, where TKI exposure may occur during critical windows of growth and puberty, and patients require treatment for prolonged periods of time. The aim of this systematic review protocol is to report on the methods used to conduct a systematic review to investigate the endometabolic and bone health effects of TKI therapy in CML. METHODS AND ANALYSIS: Searches will be conducted in the Cochrane Central Register of Controlled Trials, EMBASE and MEDLINE from inception on August 1st, 2019. Searches may be updated while performing the systematic review to ensure new evidence is included if applicable. Grey literature search will include ClinicalTrials.gov and ProQuest Dissertations and Theses A&I. We will perform a meta-analysis if there are at least two studies reporting similar populations, interventions, methods and tracking the same outcome measures. The studies should also have similar age and sex distributions. ETHICS AND DISSEMINATION: As this is a systematic review protocol, it does not include patient data; therefore, Research Ethics Board approval is not indicated. The systematic review will be published in a peer-reviewed journal and presented at international conferences. PROSPERO REGISTRATION NUMBER: CRD42018091175.

Endogenous H2S production deficiencies lead to impaired renal erythropoietin production.

INTRODUCTION: Patients suffering from chronic kidney disease (CKD) experience a number of associated comorbidities, including anemia. Relative deficiency in renal erythropoietin (EPO) production is thought to be a primary cause of anemia. Interestingly, CKD patients display low levels of hydrogen sulfide (H2S), an endogenously derived renal oxygen sensor. Previous in vitro experiments have revealed that H2S-deficient renal cell lines produce less EPO than wild-type renal cell lines during hypoxia. METHODS: We postulated that H2S might be a primary mediator of EPO synthesis during hypoxia, which was tested using an in vivo murine model of whole-body hypoxia and in clinical samples obtained from CKD patients. RESULTS: Following a 72-hour period of hypoxia (11% O2), partial H2S knockout mice (lacking the H2S biosynthetic enzyme cystathionine γ-lyase [CSE]) displayed lower levels of hemoglobin, EPO and cystathionine-ß-synthase (CBS) (another H2S biosynthetic enzyme) compared to wild-type mice, all of which was rescued by exogenous H2S supplementation. We also found that anemic CKD patients requiring exogenous EPO exhibited lower urinary thiosulfate levels compared to non-anemic CKD patients of similar CKD classification. CONCLUSIONS: Together, our results confirm an interplay between the actions of H2S during hypoxia and EPO production.

Hydrogen Sulfide Induced Erythropoietin Synthesis is Regulated by HIF Proteins.

PURPOSE: Anemia of end stage renal disease affects 90% of patients on hemodialysis and it is a tremendous concern of patients and health care providers. Renal disease creates a state of renal hypoxia, which may contribute to a lack of erythropoietin production from the kidney when low oxygen levels are sensed. This necessitates the use of exogenous erythropoietin preparations. MATERIALS AND METHODS: Recent evidence suggests that endogenously derived hydrogen sulfide may mediate oxygen sensing in tissues. Given the known involvement of other small molecules such as nitric oxide in erythropoietin production and the observation of decreased urinary H2S levels in patients with renal failure, we postulated that H2S may be the primary mediator of erythropoietin production during hypoxia. PK1, 786-O and Hep3B cells were incubated in hypoxia (1% O2) for 24 hours. Hypoxic cells were treated with the H2S donor GYY 4137 and the H2S inhibitor hydroxylamine. Following hypoxia erythropoietin, HIF-1α, HIF-2α and CBS expression was measured by quantitative real-time polymerase chain reaction and Western blot. RESULTS: Hydroxylamine administration led to a significant decrease in erythropoietin, HIF-1α, HIF-2α and CBS protein levels during hypoxia. This was rescued by administration of GYY 4137 for erythropoietin, CBS and HIF-2α. Additionally, CSE -/- mice placed in hypoxia for 72 hours showed decreased renal erythropoietin production compared to wild-type mice. CONCLUSIONS: These data suggest previously undocumented interplay of the production and action of H2S during hypoxia with subsequent erythropoietin production. The use of novel hydrogen sulfide donors could represent an alternative to standard therapies of anemia of renal failure.