Early detection versus primary prevention in the PLCO flexible sigmoidoscopy screening trial: Which has the greatest impact on mortality?

BACKGROUND: Screening for colorectal cancer (CRC) with flexible sigmoidoscopy (FS) has been shown to reduce CRC mortality. The current study examined whether the observed mortality reduction was due primarily to the prevention of incident CRC via removal of adenomatous polyps or to the early detection of cancer and improved survival. METHODS: The Prostate, Lung, Colorectal, and Ovarian (PLCO) cancer screening trial randomized 154,900 men and women aged 55 to 74 years. Individuals underwent FS screening at baseline and at 3 or 5 years versus usual care. CRC-specific survival was analyzed using Kaplan-Meier curves and proportional hazards modeling. The authors estimated the percentage of CRC deaths averted by early detection versus primary prevention using a model that applied intervention arm survival rates to CRC cases in the usual-care arm and vice versa. RESULTS: A total of 1008 cases of CRC in the intervention arm and 1291 cases of CRC in the usual-care arm were observed. Through 13 years of follow-up, there was no significant difference noted between the trial arms with regard to CRC-specific survival for all CRC (68% in the intervention arm vs 65% in the usual-care arm; P =.16) or proximal CRC (68% vs 62%, respectively; P = .11) cases; however, survival in distal CRC cases was found to be higher in the intervention arm compared with the usual-care arm (77% vs 66%; P<.0001). Within each arm, symptom-detected cases had significantly worse survival compared with screen-detected cases. Overall, approximately 29% to 35% of averted CRC deaths were estimated to be due to early detection and 65% to 71% were estimated to be due to primary prevention. CONCLUSIONS: CRC-specific survival was similar across arms in the PLCO trial, suggesting a limited role for early detection in preventing CRC deaths. Modeling suggested that approximately two-thirds of avoided deaths were due to primary prevention. Future CRC screening guidelines should emphasize primary prevention via the identification and removal of precursor lesions. Cancer 2017;123:4815-22. © 2017 American Cancer Society.

Barriers to colorectal cancer screening among Medicare consumers.

BACKGROUND: Few studies have examined lack of physician recommendation and other reasons for under-utilization of colorectal cancer (CRC) screening in the Medicare population. METHODS: Data from a telephone survey conducted in 2001 in a random sample of Medicare consumers residing in North and South Carolina were used to examine barriers to CRC screening, focusing on consumers' reports of receiving a physician's recommendation to obtain CRC screening and reasons for not being screened. Analyses were restricted to respondents with no history of CRC (n = 1901). Descriptive statistics were used to characterize respondents' CRC screening status, receipt of a physician's recommendation for screening, and reasons for not being screened. Logistic regression modeling was used to examine factors associated with receiving a physician recommendation for fecal occult blood test, sigmoidoscopy, colonoscopy, any endoscopy, and any CRC test. RESULTS: Thirty-one percent of Medicare consumers had never been tested for CRC, and 18% had been tested but were not current with Medicare-covered intervals. Overall, 28% reported not receiving a physician recommendation for screening. Predictors of receiving a physician recommendation included sociodemographic (younger age, white race, more education), health status (increased CRC risk, comorbidity), and healthcare access (had a routine/preventive care visit in the past 12 months) factors. Lack of knowledge/awareness and the physician not ordering the test were commonly cited reasons for not having CRC tests. CONCLUSIONS: Colorectal cancer screening was under-utilized by Medicare consumers in two states, and lack of physician recommendation was an important contributing factor. Providing a benefit under the Medicare program does not ensure its widespread use by consumers or their physicians.

A lay person versus a trained endoscopist: can the preop endoscopy simulator detect a difference?

The purpose of this study was to establish construct validation of a flexible sigmoidoscopy simulator by comparing training-level grouped subjects. These included clerical staff (n = 10), residents (n = 19), and experts (n = 5). Each participant performed 3 scopes. The ANOVA group-based results for trainer-measured variables are shown in Table 1. These results demonstrate that the flexible sigmoidoscopy simulator distinguished the trained from the untrained and the resident from the expert. Although there was no statistically significant differences between the senior residents and the experts, the expert commonly outperformed the residents. Establishing the transferability of simulator training to real life is next. If the transfer of skill can be established, it may give rise to a new skills training approach.