Opioid Use After Nephrectomy for Kidney Cancer in Ontario: A Population-Based Study.

OBJECTIVE: To compare the odds of early and prolonged post-operative opioid use in patients undergoing minimally invasive surgery (MIS) vs open surgery for nephrectomy. METHODS: For opioid-naïve patients in Ontario who underwent nephrectomy for kidney cancer (1994-2017, n = 7900), post-discharge opioid use was determined by prescriptions in the Ontario Drug Benefit database (age ≥65 years) and the Narcotics Monitoring System (all patients from 2012). Early opioid use was defined as ≥1 prescription 1-90 days after surgery. Two separate definitions of prolonged opioid use were examined: (1) prescription(s) for ≥60 days during post-operative days 90-365; (2) ≥1 prescriptions between both of: 1-90 days AND 91-180 days after surgery. Predictors of opioid use were assessed using multivariable generalized estimating equation logistic regression, accounting for surgeon clustering. RESULTS: Overall, 67.4% of patients received early opioid prescriptions; however, prolonged use was low, ranging from 1.6 to 4.4% of patients depending on the definition. In multivariable analysis, open nephrectomy was associated with higher odds of early opioid use compared to MIS nephrectomy (Odds Ratio [OR] 1.36, 95% Confidence Interval [CI] 1.19-1.55). Surgery type was not significantly associated with prolonged opioid use for either definition (OR 1.22, CI 0.79-1.89 and OR 1.06, CI 0.83-1.35). CONCLUSIONS: In this population-level study of patients undergoing nephrectomy for kidney cancer, patients who received open surgery were at increased odds of receiving early post-operative opioids compared to MIS. Prolonged opioid use was low overall and was not significantly with associated with type of surgery.

Factors Associated with Discontinuation of Active Surveillance among Men with Low-Risk Prostate Cancer: A Population-Based Study.

PURPOSE: The purpose of this study was to describe the uptake, discontinuation and variation of active surveillance (AS) by provider and patient level characteristics. MATERIALS AND METHODS: This observational, population-based study used linked administrative databases and pathology reports to identify all men diagnosed with Gleason score ≤6 prostate cancer (PC) between January 1, 2008 and December 31, 2014 in Ontario, Canada. The Cochran-Armitage test was used for AS trend over time. Treatment-free survival was estimated using cumulative incidence function. Factors associated with discontinuation of AS were evaluated using Cox proportional hazard models. RESULTS: Active surveillance was the initial management strategy for 8,541 cases (51%). Use of AS significantly increased from 38% in 2008 to 69% in 2014 (p=0.001). Men on AS were significantly older (64 years, SD 8.0) than those on initial treatment (62 years, SD 7.7; p=0.001). After a median followup of 48 months, 4,337 (51%) patients had discontinued AS. Treatment-free survival for AS patients at 1, 3, and 5 years were 85%, 58% and 52%, respectively. Median time to definitive treatment after initial AS was 16 months (IQR 11-25 months). Factors associated with AS discontinuation were younger age at diagnosis, year of diagnosis, higher comorbidities, treatment at academic center, treatment by physician and institution in the highest volume tertile, and adverse cancer-specific characteristics (higher prostate specific antigen [PSA], higher number of positive cores and higher percentage of core involvement at diagnosis). CONCLUSIONS: Although the uptake of AS significantly increased over time, there has been a relatively high rate of discontinuation over 5 years. Factors associated with transition to definitive treatment were younger age, care provided by higher volume physicians and institutions, higher PSA and greater PC volume at diagnosis. These results may help guide policy making, developing quality indicators, and developing targeted continued education for physician and patients embarking on AS to establish realistic expectations.

Real-World Practice Patterns and Predictors of Continuous versus Intermittent Androgen Deprivation Therapy Use for Prostate Cancer in Older Men.

PURPOSE: Phase-III randomized control trial evidence suggests intermittent androgen deprivation therapy (IADT) is not significantly inferior to continuous androgen deprivation therapy (ADT) for patients with prostate cancer (PC). However, clinical practice and guidelines differ in their recommendations. We evaluate real-world utilization and practice patterns of IADT. MATERIALS AND METHODS: Ontario men ≥65 years of age with PC who initiated ADT for ≥3 months were identified (1997-2017). Lapses in ADT ≥6 months (initial gap) and ≥3 months (subsequent gaps) were used to classify IADT. Neoadjuvant/adjuvant therapy was excluded. Disease stage adjustment was completed for patients with likely metastatic disease based on de novo presentation with ADT. Patient and physician predictors of IADT were analyzed using multivariable logistic regression. RESULTS: We identified 8,544 patients with 1,715 having previously received local therapy. Among all patients, 16.4% received IADT. This ranged from 11.4%-24.8% across health-planning regions and increased to 26.6% in those with previous local therapy. Mean followup was 8.3 years. Patients with prior local therapy (OR 1.85, 95% CI 1.59-2.17, p <0.001) and those in the highest income quintile (OR 1.32, 95% CI 1.08-1.60, p=0.005) had increased odds of receiving IADT. Radiation oncologists were more likely to use IADT than urologists (OR 1.99, 95% CI 1.59-2.50, p <0.001), as were physicians with more experience (≥10 years in practice: OR 1.44, 95% CI 1.11-1.88, p=0.007). In specialty-stratified analyses, case volume was significantly associated with IADT for radiation oncologists (highest quartile: OR 1.73, 95% CI 1.14-2.62, p=0.009). CONCLUSIONS: IADT remains underutilized for patients with PC who ≥65 years of age with only 1 in 4 to 1 in 6 eligible patients receiving this form of care. Clinical, sociodemographic and physician characteristics play an important role in treatment selection.

Long-term use of 5-alpha-reductase inhibitors is safe and effective in men on active surveillance for prostate cancer.

BACKGROUND: Although 5-alpha-reductase inhibitors (5ARIs) have been shown to benefit men with prostate cancer (PCa) on active surveillance (AS), their long-term safety remains controversial. Our objective is to describe the long-term association of 5ARI use with PCa progression in men on AS. MATERIALS/SUBJECTS AND METHODS: The cohort of men with low-risk PCa was derived from a prospectively maintained AS database at the Princess Margaret (1995-2016). Pathologic, grade, and volume progression were the primary end points. Kaplan-Meier time-to-event analysis was performed and Cox proportional hazards regression was used to determine predictors of progression where 5ARI exposure was analyzed as a time-dependent variable. Patients who came off AS prior to any progression events were censored at that time. RESULTS: The cohort included 288 men with median follow-up of 82 months (interquartile range: 37-120 months). Among non-5ARI users (n = 203); 114 men (56.2%) experienced pathologic progression compared with 24 men (28.2%) in the 5ARI group (n = 85), (p < 0.001). Grade and volume progression were higher in the non-5ARI group compared with the 5ARI group (n = 82; 40.4% vs. n = 19; 22.4% respectively, p = 0.003 for grade progression; n = 87; 43.1% and n = 15; 17.7%, respectively for volume progression p < 0.001). Lack of 5ARI use was independently positively associated with pathologic progression (HR: 2.65; CI: 1.65-4.24), grade progression (HR: 2.75; CI: 1.49-5.06), and volume progression (HR: 3.15; CI: 1.78-5.56). The frequency of progression to high-grade (Grade Group 4-5) tumors was not significantly different between the groups. CONCLUSIONS: Use of 5ARIs diminished both grade and volume progression without an increased risk of developing Grade Groups 4-5 disease.

Impact of Abiraterone Acetate and Enzalutamide on Symptom Burden of Patients with Chemotherapy-naive Metastatic Castration-resistant Prostate Cancer.

AIMS: Treatments and disease burden of metastatic castration-resistant prostate cancer (mCRPC) considerably affect a patient's quality of life. However, patient-reported symptom burden data are still largely insufficient. This study sought to compare the self-reported symptom burden of men with chemotherapy-naive (CN) mCRPC treated with abiraterone acetate (AA) or enzalutamide (EZ) in routine clinical practice. MATERIALS AND METHODS: Between 2011 and 2015, 189 CN-mCRPC patients who had received AA (n = 76) or EZ (n = 113) at the Princess Margaret Cancer Centre were included. The Edmonton Symptom Assessment System (ESAS) score, baseline demographic information, comorbidities, Eastern Cooperative Oncology Group performance status, laboratory data and narcotic analgesic use were recorded for each patient. The minimal clinically important difference was assessed using ±1 point change from baseline for each ESAS symptom. Mixed model for repeated measures (MMRM) was used to estimate and compare the longitudinal ESAS score changes from baseline in AA and EZ groups adjusted for age, baseline ESAS scores, treatment group, treatment duration and time. RESULTS: The median (interquartile range) treatment duration with AA and EZ was 10 (6-16) and 12 (7-18) months, respectively (P = 0.19). Fatigue was rated the most distressing symptom at baseline and following treatment in both groups. There were no statistically significant differences in the proportion of patients with clinically meaningful symptom improvement or worsening after AA or EZ administration in any of the ESAS-based physical and psychological symptoms over time. In MMRM analyses, there were no significant differences in adjusted mean scores from baseline to 3, 6, 9 and 12 months for any of the ESAS items between AA and EZ groups. CONCLUSION: Physical and psychological symptoms assessed by ESAS were comparable in CN-mCRPC men treated with AA or EZ in the real-world clinical setting. Further studies are warranted to confirm these findings.