Seth Tyree

Trends in stage‐specific incidence rates for urothelial carcinoma of the bladder in the United States: 1988 to 2006

Bladder cancer is notable for a striking heterogeneity of disease‐specific risks. Among the approximately 75% of incident cases found to be superficial to the muscularis propria at the time of presentation (non–muscle‐invasive bladder cancer), the risk of progression to the lethal phenotype of muscle‐invasive disease is strongly associated with stage and grade of disease. Given the suggestion of an increasing percentage of low‐risk cases in hospital‐based registry data in recent years, the authors hypothesized that population‐based data may reveal changes in the stage distribution of early‐stage cases.

A surveillance system for monitoring, public reporting, and improving minority access to cancer clinical trials:

Background The Institute of Medicine (IOM) has recommended that each person with cancer should have access to clinical trials, which have been associated with improving care quality and disparities. With no effective enrollment monitoring system, patterns of trial enrollment remain unclear. Purpose We developed a population-based, statewide system designed to facilitate monitoring of cancer trial enrollment and targeting of future interventions to improve it. Methods Person-level cancer incidence data from the North Carolina Central Cancer Registry (NCCCR), person-level treatment trial accrual data from the National Cancer Institute (NCI), and county-level Area Resource Files (ARF) measures for 12 years, 1996–2007, were studied. Deidentified person-level data necessitated county-level analysis. Enrollment rates were estimated as the ratio of trial enrollment to cancer incidence for each race, gender, year, and county combination. Multivariable analysis examined factors associated with trial accrual. Sensitivity analyses examined spurious fluctuations and temporal discordance of incidence and enrollment. Results The NCI treatment trial enrollment rate was 2.39% for whites and 2.20% for minorities from 1996 to 2007, and 2.88% and 2.47%, respectively, from 2005 to 2007. Numerous counties had no minority enrollment. The 2005–2007 enrollment rates for white and minority females was 4.04% and 3.59%, respectively, and for white and minority males was 1.74% and 1.36%, respectively. Counties with a medical school or NCI Community Clinical Oncology Program (CCOP)-affiliated practice had higher trial enrollment. Limitations We examined NCI trial accrual only – industry-sponsored and investigator-initiated trials were excluded; however, studies comprise the majority of all clinical trial participants. Delays in data availability may hinder the immediacy of population-based analyses. Conclusions Model stability and consistency suggest that this system is effective for population-based enrollment surveillance. For North Carolina, it suggests a worsening disparity in minority trial enrollment, though our analyses elucidate targets for intervention. Regional enrollment variation suggests the importance of access to clinical research networks and infrastructure. Substantial gender differences merit further examination.

Regional variation in colorectal cancer testing and geographic availability of care in a publicly insured population.

Despite its demonstrated effectiveness, colorectal cancer (CRC) testing is suboptimal, particularly in vulnerable populations such as those who are publicly insured. Prior studies provide an incomplete picture of the importance of the intersection of multilevel factors affecting CRC testing across heterogeneous geographic regions where vulnerable populations live. We examined CRC testing across regions of North Carolina by using population-based Medicare and Medicaid claims data from disabled individuals who turned 50 years of age during 2003-2008. We estimated multilevel models to examine predictors of CRC testing, including distance to the nearest endoscopy facility, county-level endoscopy procedural rates, and demographic and community contextual factors. Less than 50% of eligible individuals had evidence of CRC testing; men, African-Americans, Medicaid beneficiaries, and those living furthest away from endoscopy facilities had significantly lower odds of CRC testing, with significant regional variation. These results can help prioritize intervention strategies to improve CRC testing among publicly insured, disabled populations.

Enrollment and Racial Disparities in Cancer Treatment Clinical Trials in North Carolina

BACKGROUND Clinical trials provide access to innovative, high-quality cancer treatment. Simultaneously, broad access helps to ensure that trials include heterogeneous patient populations, which improves the generalizability of findings and the development of interventions that are effective for diverse populations. We provide updated data describing enrollment into cancer treatment trials in North Carolina. METHODS For the period 1996–2009, person-level data regarding cancer clinical trial enrollment and cancer incidence were obtained from the North Carolina Central Cancer Registry and the National Cancer Institute (NCI). Enrollment rates were estimated as the ratio of trial enrollment to cancer incidence for race, sex, and year for each county, Area Health Education Center region, and the state overall. Enrollment rates for common cancers are presented. RESULTS From 1996 to 2009, North Carolina NCI treatment trial enrollment rates were 2.4% and 2.2% for white patients and minority patients, respectively. From 2007 to 2009, rates were 3.8% for white women, 3.5% for minority women, 1.3% for white men, and 1.0% for minority men; there was greater enrollment among more urban populations (2.4%) than among the most rural populations (1.5%). LIMITATIONS This study is limited to NCI-sponsored treatment trials in North Carolina. Policies governing collection of original data necessitate a delay in data availability. CONCLUSIONS Effort is needed to ensure trial access and enrollment among all North Carolina populations. Specifically, we identified racial and sex disparities, particularly for certain cancers (eg, breast cancer). Programs in North Carolina and across the nation can use the methods we employed to assess their success in broadening clinical trial enrollment to include diverse populations.