Background: This retrospective cohort study sought to characterize the accrual of patients with cancer into clinical trials at the time of diagnosis and analyze the impact of accrual on survival. Methods: The National Cancer Database (NCDB) was queried for patients enrolled in clinical trials at their initial course of treatment for 46 cancers from 2004 through 2015. Descriptive statistics were used to characterize the accrual of patients with cancer in clinical trials at diagnosis, and Kaplan-Meier graphical displays, log-rank tests, odds ratios, and stratified Cox proportional hazards models were used to analyze the impact of accrual on overall survival (OS). Strata were defined using 10 variables. Model-based adjusted survival curves of 2 groups were reverse-generated based on a Weibull distribution. Results: Of 12,097,681 patients in the NCDB, 11,576 (0.1%) were enrolled in trials. Patients in clinical trials typically had metastatic disease (30.9% vs 16.4%; P<.0001), were white (88.0% vs 84.8%; P<.0001), had private/managed care insurance (56.4% vs 41.8%; P<.0001), had fewer comorbidities (Charlson-Deyo score 0: 81.9% vs 75.7%; P<.0001, and Charlson-Deyo scores 1–3: 18.1% vs 24.3%; P<.0001) compared with those not in trials. At a median follow-up of 64 months, enrollment in a clinical trial was associated with improved OS in univariate and stratified analyses, with a median survival of 60.0 versus 52.5 months (hazard ratio, 0.876; 95% CI, 0.845–0.907; P<.0001). Stratified analysis with matched baseline characteristics between patients enrolled and not enrolled in a clinical trial showed superior OS at 5 years (95.0% vs 90.2%; P<.0001). Conclusions: Enrollment in clinical trials at first line of therapy in the United States is exceedingly low and favors young, healthy, white patients with metastatic disease and private insurance who are treated at academic medical centers. Patients with cancer treated in clinical trials live longer than those not treated in trials.
Nicholas G. Zaorsky, Ying Zhang, Vonn Walter, Leila T. Tchelebi, Vernon M. Chinchilli and Niraj J. Gusani
Kelsey C. Stoltzfus, Biyi Shen, Leila Tchelebi, Daniel M. Trifiletti, Niraj J. Gusani, Vonn Walter, Ming Wang and Nicholas G. Zaorsky
Background: Increased facility surgical treatment volume is sometimes associated with improved survival in patients with cancer; however, published studies evaluating volume are heterogeneous and disparate in their patient inclusion and definition of volume. The purpose of this work was to evaluate uniformly the impact of surgical facility volume on survival in patients with cancer. Methods: The National Cancer Database was searched for patients diagnosed in 2004 through 2013 with the 12 cancers most commonly treated surgically. Facilities were stratified by 4 categories using the overall population (low, intermediate, high, and very high), each including 25% of patients, and then stratified by each individual disease site. Five-year postsurgery survival was estimated using both the Kaplan-Meier method and corresponding log-rank tests for group comparisons. Cox proportional hazard models were used to evaluate the effects of facility volume on 5-year postsurgery survival further, adjusted for multiple covariates. Results: A total of 3,923,618 patients who underwent surgery were included from 1,139 facilities. Of these, 40.4% had breast cancer, 12.8% prostate cancer, and 10.0% colon cancer. Most patients were female (65.0%), White (86.4%), and privately insured (51.6%) with stage 0–III disease (64.8%). For all cancers, the risk of death for patients undergoing surgery at very high-volume facilities was 88% of that for those treated at low-volume facilities. Hazard ratios (HRs) were greatest (very high vs low volume) for cancer of the prostate (HR, 0.66; 95% CI, 0.63–0.69), pancreas (HR, 0.75; 95% CI, 0.71–0.78), and esophagus (HR, 0.78; 95% CI, 0.73–0.83), and for melanoma (HR, 0.81; 95% CI, 0.78–0.84); differences were smallest for uterine and non–small cell lung cancers. Overall survival differences were greatest for cancers of the brain, pancreas, and esophagus. Conclusions: Patients treated surgically at higher-volume facilities consistently had improved overall survival compared with those treated at low-volume centers, although the magnitude of difference was cancer-specific.