Doria‐Rose, V. Paul

Objective To examine whether receiving a fecal occult blood test after a negative sigmoidoscopy reduced mortality from colorectal cancer. Methods We used a nested case–control design with incidence-density matching in historical cohorts of 1,877,740 50–90-year-old persons during 2006–2012, in an integrated health-system setting. We selected 1758 average risk patients who died from colorectal cancer and 3503 matched colorectal cancer-free persons. Colorectal cancer-specific death was ascertained from cancer and mortality registries. Screening histories were determined from electronic and chart–audit clinical data in the 5- to 10-year period prior to the reference date. We evaluated receipt of subsequent fecal occult blood test within five years of the reference date among patients with negative sigmoidoscopy two to six years before the reference date. Results Of the 5261 patients, 831 patients (204 colorectal cancer deaths/627 controls) had either negative sigmoidoscopy only ( n = 592) or negative sigmoidoscopy with subsequent screening fecal occult blood test ( n = 239). Fifty-six (27.5%) of the 204 patients dying of colorectal cancer and 183 (29.2%) of the 627 colorectal cancer-free patients received fecal occult blood test following a negative sigmoidoscopy. Conditional regressions found no significant association between fecal occult blood test receipt and colorectal cancer death risk, overall (adjusted odds ratio = 0.93, confidence interval: 0.65–1.33), or for right (odds ratio = 1.02, confidence interval: 0.65–1.60) or left-colon/rectum (odds ratio = 0.77, confidence interval: 0.39–1.52) cancers. Similar results were obtained in sensitivity analyses with alternative exposure ascertainment windows or timing of fecal occult blood test. Conclusions Our results suggest that receipt of at least one fecal occult blood test during the several years after a negative sigmoidoscopy did not substantially reduce mortality from colorectal cancer.

Background Often in randomized controlled trials of cancer screening, cause of death is determined by a mortality review committee. However, little is known regarding how findings from mortality review compare to those from death certificates alone. Purpose To examine the results of four different U. S. trials of cancer screening when death certificate data only were used, as compared to results using all available mortality review information. Methods Trials included were the Health Insurance Plan of New York breast screening trial (HIP), the Minnesota trial of fecal occult blood testing, and the Johns Hopkins and Mayo Lung Projects, which each examined chest x-ray and sputum cytology. The sensitivity, specificity, positive and negative predictive values, and Cohen’s kappa for death certificates were calculated for all arms of all trials. Separate intention-to-screen analyses were conducted for each trial using cause of death information from either death certificates alone or full mortality review data. Results Generally there was excellent agreement between the death certificates and the mortality review committee as to the underlying cause of death (kappa >0.85 in all cases); death certificate agreement was similar between arms in all trials. Modest changes in the screening effectiveness estimates were observed when mortality review information was utilized, ranging from a 9% decrease to a 2% increase in the calculated mortality rate ratios. However, in one instance (HIP) a statistically significant benefit of screening was observed when mortality review committee data were used (rate ratio (RR) 0.77, 95% confidence interval (CI) 0.62— 0.95) but not when death certificate data were used (RR 0.82, 95% CI 0.65—1.03). Limitations Although considered to be the gold standard, even carefully conducted mortality review may result in errors in cause of death assignment. Conclusions For each trial, results were similar regardless of the source of cause of death information. Clinical Trials 2010; 7: 69—77. http://ctj.sagepub.com

Abstract Current users of postmenopausal hormones (PMH) have ∼30% to 40% lower risk of colorectal cancer (CRC), although associations with specific types of hormones have been inconsistent. Further, it is not clear whether some tumor types have a different risk. We conducted a case-control study to examine the relationship between PMH and CRC. Cases (n = 1,004), ages 50 to 74 years, were identified from the Surveillance Epidemiology and End Results registry in Washington from 1998 to 2002; controls (n = 1,062) were randomly selected from population lists. Case tissue samples were obtained for microsatellite instability (MSI) analyses. Interviews collected risk-factor data for CRC, including detailed information on PMH. Multivariable logistic regression models estimated odds ratios (OR) and 95% confidence intervals (95% CI). Current use of any PMH was associated with a 20% reduction in CRC risk (95% CI 0.6–0.9). This reduction in risk was limited to women who had taken estrogen plus progestin (EP) preparations only (OR = 0.6, 95% CI 0.5–0.9); there was no association with estrogen-only (E alone) use (OR = 0.9, 95% CI 0.7–1.1). For women with MSI-low or MSI-stable tumors, there was a statistically significant 40% reduction in CRC risk associated with EP use (95% CI 0.4–0.9); there was no clear association with MSI-high tumors. EP use was associated with a decreased risk of CRC; however, there seemed to be no association with E alone data that are consistent with the recent Women's Health Initiative findings. Progestin may enhance the estrogenic effect of conjugated estrogen so the combination may be more biologically active in the colon than E alone. [Cancer Res 2007;67(15):7534–9]