Faculty Bibliography

BACKGROUND:Patients on surveillance for clinical stage I (CSI) testicular cancer are counseled regarding their baseline risk of relapse. The conditional risk of relapse (cRR), which provides prognostic information on patients who have survived for a period of time without relapse, have not been determined for CSI testicular cancer. OBJECTIVE:To determine cRR in CSI testicular cancer. DESIGN, SETTING, AND PARTICIPANTS:We reviewed 1239 patients with CSI testicular cancer managed with surveillance at a tertiary academic centre between 1980 and 2014. OUTCOME MEASUREMENTS AND STATISTICAL ANALYSIS: cRR estimates were calculated using the Kaplan-Meier method. We stratified patients according to validated risk factors for relapse. We used linear regression to determine cRR trends over time. RESULTS AND LIMITATIONS:At orchiectomy, the risk of relapse within 5 yr was 42.4%, 17.3%, 20.3%, and 12.2% among patients with high-risk nonseminomatous germ cell tumor (NSGCT), low-risk NSGCT, seminoma with tumor size ≥3cm, and seminoma with tumor size <3cm, respectively. However, for patients without relapse within the first 2 yr of follow-up, the corresponding risk of relapse within the next 5 yr in the groups was 0.0%, 1.0% (95% confidence interval [CI] 0.3-1.7%), 5.6% (95% CI 3.1-8.2%), and 3.9% (95% CI 1.4-6.4%). Over time, cRR decreased (p≤0.021) in all models. Limitations include changes to surveillance protocols over time and few late relapses. CONCLUSIONS:After 2 yr, the risk of relapse on surveillance for CSI testicular cancer is very low. Consideration should be given to adapting surveillance protocols to individualized risk of relapse based on cRR as opposed to static protocols based on baseline factors. This strategy could reduce the intensity of follow-up for the majority of patients. PATIENT SUMMARY:Our study is the first to provide data on the future risk of relapse during surveillance for clinical stage I testicular cancer, given a patient has been without relapse for a specified period of time.

BACKGROUND:Statin use has been associated with improved survival outcomes in various malignancies. Randomized controlled trials are currently underway evaluating their utility as adjunctive cancer therapies. However, studies evaluating the association between statin use and outcomes in kidney cancer yield conflicting results. METHODS:We searched MEDLINE and EMBASE to identify studies evaluating the association between statin use and kidney cancer survival outcomes. We evaluated risk of bias with the Newcastle-Ottawa Scale. We pooled hazard ratios for recurrence-free survival, progression-free survival, cancer-specific survival, and overall survival using random-effects models. We evaluated publication bias through Begg's and Egger's tests, and the trim and fill procedure. RESULTS:We identified 12 studies meeting inclusion criteria and summarized data from 18,105 patients. No study was considered to be at high risk of bias. Statin use was not significantly associated with recurrence-free survival (pooled HR 0.97, 95% CI 0.89-1.06) or progression-free survival (pooled HR 0.92, 95% CI 0.51-1.65); however, statin use was associated with marked improvements in cancer-specific survival (pooled HR 0.67, 95% CI 0.47-0.94) and overall survival (pooled HR 0.74, 95% CI 0.63-0.88). There was no strong evidence of publication bias for any outcome. CONCLUSIONS:Our results demonstrate that statin use among patients with kidney cancer is associated with significantly improved cancer-specific and overall survival. Further studies are needed to confirm the therapeutic role of statins in kidney cancer.

OBJECTIVE: To determine the association between vasectomy and prostate cancer, adjusting for measures of health seeking behaviour. DESIGN/METHODS: Population based matched cohort study. SETTING/METHODS: Multiple validated healthcare databases in Ontario, Canada, 1994-2012. PARTICIPANTS/METHODS: 326 607 men aged 20 to 65 who had undergone vasectomy were identified through physician billing codes and matched 1:1 on age (within two years), year of cohort entry, comorbidity score, and geographical region to men who did not undergo a vasectomy. MAIN OUTCOMES MEASURES/METHODS: The primary outcome was incident prostate cancer. Secondary outcomes were prostate cancer related grade, stage, and mortality. RESULTS: 3462 incident cases of prostate cancer were identified after a median follow-up of 10.9 years: 1843 (53.2%) in the vasectomy group and 1619 (46.8%) in the non-vasectomy group. In unadjusted analysis, vasectomy was associated with a slightly increased risk of incident prostate cancer (hazard ratio 1.13, 95% confidence interval 1.05 to 1.20). After adjustment for measures of health seeking behaviour, however, no association remained (adjusted hazard ratio 1.02, 95% confidence interval 0.95 to 1.09). Moreover, no association was found between vasectomy and high grade prostate cancer (adjusted odds ratio 1.05, 95% confidence interval 0.67 to 1.66), advanced stage prostate cancer (adjusted odds ratio 1.04, 0.81 to 1.34), or mortality (adjusted hazard ratio 1.06, 0.60 to 1.85). CONCLUSION/CONCLUSIONS: The findings do not support an independent association between vasectomy and prostate cancer.

Survival rates in kidney cancer have improved little over time, and diabetes may be an independent risk factor for poor survival in kidney cancer. We sought to determine whether medications with putative anti-neoplastic properties (statins, metformin and non-steroidal anti-inflammatory drugs (NSAIDs)) are associated with survival in diabetics with kidney cancer. We conducted a population-based cohort study utilizing linked healthcare databases in Ontario, Canada. Patients were aged 66 or older with newly diagnosed diabetes and a subsequent diagnosis of incident kidney cancer. Receipt of metformin, statins or NSAIDs was defined using prescription claims. The primary outcome was all-cause mortality and the secondary outcome was cancer-specific mortality. We used multivariable Cox proportional hazard regression, with medication use modeled with time-varying and cumulative exposure analyses to account for intermittent use. During the 14-year study period, we studied 613 patients. Current statin use was associated with a markedly reduced risk of death from any cause (adjusted hazard ratio 0.74; 95% CI 0.59-0.91) and death due to kidney cancer (adjusted hazard ratio 0.71; 95% CI 0.51-0.97). However, survival was not associated with current use of metformin or NSAIDs, or cumulative exposure to any of the medications studied. Among diabetic patients with kidney cancer, survival outcomes are associated with active statin use, rather than total cumulative use. These findings support the use of randomized trials to confirm whether diabetics with kidney cancer should be started on a statin at the time of cancer diagnosis to improve survival outcomes.

PURPOSE:Studies evaluating the association between statin use and survival outcomes in renal cell carcinoma have demonstrated conflicting results. Our objective was to evaluate this association in a large clinical cohort by using propensity score methods to reduce confounding from measured covariates. METHODS:We performed a retrospective review of 893 patients undergoing nephrectomy for unilateral, M0 renal cell carcinoma between 2000 and 2014 at a tertiary academic center. Inverse probability of treatment weights were derived from a propensity score model based on clinical, surgical, and pathological characteristics. We used Cox proportional hazard models to evaluate the association between statin use and disease-free survival, cancer-specific survival, and overall survival in the sample weighted by the inverse probability of treatment weights. A secondary analysis was performed matching statin users 1:1 to statin nonusers on the propensity score. RESULTS:Of the 893 patients, 259 (29%) were on statins at the time of surgery. Median follow-up was 47 months (interquartile range: 20-80). Statin use was not significantly associated with disease-free survival (hazard ratio [HR] = 1.09, 95% CI: 0.65-1.81), cancer-specific survival (HR = 0.90, 95% CI: 0.40-2.01), or overall survival (HR = 0.89, 95% CI: 0.55-1.44). Similar results were observed when using propensity score matching. CONCLUSIONS:The present study found no significant association between statin use and kidney cancer outcomes. Population-based studies are needed to further evaluate the role of statins in kidney cancer therapy.

BACKGROUND:Previous studies have demonstrated that elevated neutrophil-to-lymphocyte ratios and platelet-to-lymphocyte ratios (PLRs) are associated with the presence of various malignancies. The present study evaluated various hematologic parameters and their association with renal tumor biopsy pathology. MATERIALS AND METHODS/METHODS:The clinical, hematologic, and pathologic parameters were obtained through a retrospective review of 475 diagnostic biopsy specimens of small renal masses from January 2001 to December 2013. The complete blood counts closest to and before the biopsies were obtained. The biopsy pathologic findings were divided into 3 groups: benign, primary renal malignancy, and nonrenal malignancy. The hematologic parameters were compared among the 3 groups. Receiver operating characteristic curves were constructed for the parameters that were significantly different among the groups. Multiple logistic regression models were used to assess whether the clinical and hematologic parameters were associated with benign or malignant pathologic findings. RESULTS:Hematologic parameters were available for 462 cases (97%). Pathologic examination of the biopsy specimens demonstrated benign, primary renal malignancy, and nonrenal malignancy in 114 (25%), 337 (73%), and 11 (2%) patients, respectively. The PLR was significantly (P = .010) different among the 3 groups and was significantly (P = .013) greater in those with nonrenal malignancies than in those with primary renal malignancies. Using a cutoff for the PLR of 202.9 gave a sensitivity of 63.6% and specificity of 82.2% for detecting a nonrenal malignancy. CONCLUSION/CONCLUSIONS:The hematologic parameters did not differ significantly between benign and primary renal malignant masses undergoing biopsy. The PLR might be useful as a simple and inexpensive marker to help distinguish nonrenal malignancies in the workup of a small renal mass.

INTRODUCTION/BACKGROUND:Institutional experience has been associated with improved outcomes for various malignancies, including testicular cancer. The present study evaluated whether institution at orchiectomy was associated with outcomes on active surveillance (AS) for clinical stage (CS) I germ cell tumours (GCT). METHODS:815 patients with CSI GCT managed with AS at the Princess Margaret Cancer Centre were identified. Princess Margaret is a tertiary academic institution with a multidisciplinary testicular cancer clinic involving radiation oncologists, medical oncologists, and urologists, and has research experience in testicular cancer care. The association between institution of orchiectomy (Princess Margaret vs. Other) and time to progression on AS was analyzed using multivariable Cox proportional hazards models. Academic vs. non-academic institutions were compared in a sensitivity analysis. RESULTS:Patients undergoing orchiectomy at Princess Margaret for non-seminoma GCT were significantly less likely to have pure embryonal carcinoma (EC) in orchiectomy pathology (odds ratio [OR] 0.33; p=0.008) and CSIB disease (OR 0.47; p=0.014). Seminoma characteristics did not differ significantly between institution groups. In non-seminoma GCT, median followup was 5.4 years, 27% progressed on AS, and institution of orchiectomy was not associated with time to progression in either univariate (hazard ratio [HR] 0.79; p=0.33) or multivariable analyses (HR 1.01; p=0.97). In seminoma, median followup was 4.7 years, 12% progressed on AS, and institution of orchiectomy was not associated with progression (univariate: HR 0.87; p=0.73; multivariable: HR 0.98; p=0.96). Sensitivity analyses demonstrated similar results. CONCLUSIONS:Among CSI GCT patients managed on AS at a specialized cancer centre, there appears to be no difference in oncologic outcomes based upon the institution where orchiectomy was performed.