The effect of using fecal testing after a negative sigmoidoscopy on the risk of death from colorectal cancer

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.

A population-based survey to assess the association between cannabis and quality of life among colorectal cancer survivors

Background

As more states legalize cannabis for medical and recreational use, people increasingly use cannabis to treat medical conditions and associated symptoms. The prevalence and utility of cannabis for cancer-related symptoms may be clarified by examining cannabis use among patients with a common cancer diagnosis. We aimed to determine the prevalence of cannabis use among colorectal cancer (CRC) survivors and its associations with quality of life (QoL) and cancer-related symptomatology.

Methods

A cross-sectional survey of patient-reported QoL outcomes and behaviors, including cannabis use, was conducted within the Patient Outcomes To Advance Learning network’s (PORTAL) CRC Cohort. The cohort included a population-based sample of healthcare system members ≥18 years old diagnosed with adenocarcinoma of the colon or rectum from 2010 through 2016. We assessed the association between cannabis use and QoL using the European Organization for Research and Treatment of Cancer QLQ-C30 summary score.

Results

Of the 1784 respondents, 293 (16.4%) reported cannabis use following CRC diagnosis. Current tobacco smokers were more likely to use cannabis compared to former or never tobacco smokers (adjusted odds ratio [aOR] 2.71, 95% confidence interval [CI] 1.56 to 4.70). Greater alcohol use (> 4 drinks per month versus ≤4 drinks per month) was associated with cannabis use (aOR 2.17, 95% CI 1.65 to 2.85). There was an association between cannabis use and cancer stage at diagnosis, with stage 3 or 4 CRC patients more likely to use cannabis than stage 1 or 2 CRC patients (aOR 1.68, 95% CI 1.25 to 2.25). After adjusting for demographics, medical comorbidities, stage and site of CRC diagnosis, and prescription opioid use, people who used cannabis had significantly lower QoL than people who did not use cannabis (difference of − 6.14, 95% CI − 8.07 to − 4.20).

Conclusion

Among CRC survivors, cannabis use was relatively common, associated with more advanced stages of disease, associated with tobacco and alcohol use, and not associated with better QoL. Clinicians should inquire about cannabis use among their patients and provide evidence-based recommendations for cancer-related symptoms.

Cumulative Burden of Colorectal Cancer-Associated Genetic Variants Is More Strongly Associated With Early-Onset vs Late-Onset Cancer

BACKGROUND & AIMS

Early-onset colorectal cancer (CRC, in persons younger than 50 years old) is increasing in incidence; yet, in the absence of a family history of CRC, this population lacks harmonized recommendations for prevention. We aimed to determine whether a polygenic risk score (PRS) developed from 95 CRC-associated common genetic risk variants was associated with risk for early-onset CRC.

METHODS

We studied risk for CRC associated with a weighted PRS in 12,197 participants younger than 50 years old vs 95,865 participants 50 years or older. PRS was calculated based on single nucleotide polymorphisms associated with CRC in a large-scale genome-wide association study as of January 2019. Participants were pooled from 3 large consortia that provided clinical and genotyping data: the Colon Cancer Family Registry, the Colorectal Transdisciplinary Study, and the Genetics and Epidemiology of Colorectal Cancer Consortium and were all of genetically defined European descent. Findings were replicated in an independent cohort of 72,573 participants.

RESULTS

Overall associations with CRC per standard deviation of PRS were significant for early-onset cancer, and were stronger compared with late-onset cancer (P for interaction = .01); when we compared the highest PRS quartile with the lowest, risk increased 3.7-fold for early-onset CRC (95% CI 3.28-4.24) vs 2.9-fold for late-onset CRC (95% CI 2.80-3.04). This association was strongest for participants without a first-degree family history of CRC (P for interaction = 5.61 × 10-5). When we compared the highest with the lowest quartiles in this group, risk increased 4.3-fold for early-onset CRC (95% CI 3.61-5.01) vs 2.9-fold for late-onset CRC (95% CI 2.70-3.00). Sensitivity analyses were consistent with these findings.

CONCLUSIONS

In an analysis of associations with CRC per standard deviation of PRS, we found the cumulative burden of CRC-associated common genetic variants to associate with early-onset cancer, and to be more strongly associated with early-onset than late-onset cancer, particularly in the absence of CRC family history. Analyses of PRS, along with environmental and lifestyle risk factors, might identify younger individuals who would benefit from preventive measures.

Long-term Risk of Colorectal Cancer and Related Death After Adenoma Removal in a Large, Community-based Population

BACKGROUND & AIMS

The long-term risks of colorectal cancer (CRC) and CRC-related death following adenoma removal are uncertain. Data are needed to inform evidence-based surveillance guidelines, which vary in follow-up recommendations for some polyp types. Using data from a large, community-based integrated health care setting, we examined the risks of CRC and related death by baseline colonoscopy adenoma findings.

METHODS

Participants at 21 medical centers underwent baseline colonoscopies from 2004 through 2010; findings were categorized as no-adenoma, low-risk adenoma, or high-risk adenoma. Participants were followed until the earliest of CRC diagnosis, death, health plan disenrollment, or December 31, 2017. Risks of CRC and related deaths among the high- and low-risk adenoma groups were compared with the no-adenoma group using Cox regression adjusting for confounders.

RESULTS

Among 186,046 patients, 64,422 met eligibility criteria (54.3% female; mean age, 61.6 ± 7.1 years; median follow-up time, 8.1 years from the baseline colonoscopy). Compared with the no-adenoma group (45,881 patients), the high-risk adenoma group (7563 patients) had a higher risk of CRC (hazard ratio [HR] 2.61; 95% confidence interval [CI] 1.87-3.63) and related death (HR 3.94; 95% CI 1.90-6.56), whereas the low-risk adenoma group (10,978 patients) did not have a significant increase in risk of CRC (HR 1.29; 95% CI 0.89-1.88) or related death (HR 0.65; 95% CI 0.19-2.18).

CONCLUSIONS

With up to 14 years of follow-up, high-risk adenomas were associated with an increased risk of CRC and related death, supporting early colonoscopy surveillance. Low-risk adenomas were not associated with a significantly increased risk of CRC or related deaths. These results can inform current surveillance guidelines for high- and low-risk adenomas.

Diabetes in relation to Barrett's esophagus and adenocarcinomas of the esophagus: A pooled study from the International Barrett's and Esophageal Adenocarcinoma Consortium

BACKGROUND

Diabetes is positively associated with various cancers, but its relationship with tumors of the esophagus/esophagogastric junction remains unclear.

METHODS

Data were harmonized across 13 studies in the International Barrett's and Esophageal Adenocarcinoma Consortium, comprising 2309 esophageal adenocarcinoma (EA) cases, 1938 esophagogastric junction adenocarcinoma (EGJA) cases, 1728 Barrett's esophagus (BE) cases, and 16,354 controls. Logistic regression was used to estimate study-specific odds ratios (ORs) and 95% CIs for self-reported diabetes in association with EA, EGJA, and BE. Adjusted ORs were then combined using random-effects meta-analysis.

RESULTS

Diabetes was associated with a 34% increased risk of EA (OR, 1.34; 95% CI, 1.00-1.80; I2  = 48.8% [where 0% indicates no heterogeneity, and larger values indicate increasing heterogeneity between studies]), 27% for EGJA (OR, 1.27; 95% CI, 1.05-1.55; I2  = 0.0%), and 30% for EA/EGJA combined (OR, 1.30; 95% CI, 1.06-1.58; I2  = 34.9%). Regurgitation symptoms modified the diabetes-EA/EGJA association (P for interaction = .04) with a 63% increased risk among participants with regurgitation (OR, 1.63; 95% CI, 1.19-2.22), but not among those without regurgitation (OR, 1.03; 95% CI, 0.74-1.43). No consistent association was found between diabetes and BE.

CONCLUSIONS

Diabetes was associated with increased EA and EGJA risk, which was confined to individuals with regurgitation symptoms. Lack of an association between diabetes and BE suggests that diabetes may influence progression of BE to cancer.

Effect of Sex, Age, and Positivity Threshold on Fecal Immunochemical Test Accuracy: A Systematic Review and Meta-analysis

BACKGROUND & AIMS

Quantitative fecal immunochemical tests (FITs) for hemoglobin are commonly used for colorectal cancer (CRC) screening. We aimed to quantify the change in CRC and advanced adenoma detection and number of positive test results at different positivity thresholds and by sex and age.

METHODS

We searched MEDLINE and EMBASE, selecting articles of FIT for CRC detection in asymptomatic adults undergoing screening. We calculated sensitivity and specificity, as well as detected number of cancers, advanced adenomas, and positive test results at positivity thresholds ≤10 μg hemoglobin/g feces, 10 to ≤20 μg/g, 20 to ≤30 μg/g, and >30 μg/g. We also analyzed results from stratified by patient sex, age, and reference standard.

RESULTS

Our meta-analysis comprised 46 studies with 2.4 million participants and 6478 detected cancers. Sensitivity for detection of CRC increased from 69% (95% confidence interval [CI], 63%-75%) at thresholds >10 μg/g and ≤20 μg/g to 80% (95% CI, 76%-83%) at thresholds ≤10 μg/g. At these threshold values, sensitivity for detection of advanced adenomas increased from 21% (95% CI, 18%-25%) to 31% (95% CI, 27%-35%), whereas specificity decreased from 94% (95% CI, 93%-96%) to 91% (95% CI, 89%-93%). In 3 studies stratified by sex, sensitivity of CRC detection was 77% in men (95% CI, 75%-79%) and 81% in women (95% CI, 60%-100%) (P = .68). In 3 studies stratified by age groups, sensitivity of CRC detection was 85% for ages 50-59 years (95% CI, 71%-99%) and 73% for ages 60-69 years (95% CI, 71%-75%) (P = .10). All studies with colonoscopy follow-up had similar sensitivity levels for detection of CRC to studies that analyzed 2-year registry follow-up data (74%; 95% CI, 68%-78% vs 75%; 95% CI, 73%-77%).

CONCLUSIONS

In a meta-analysis of studies that analyzed detection of CRC and advanced adenomas at different FIT positivity thresholds, we found the sensitivity and specificity of detection to vary with positive cutoff value. It might be possible to decrease positive threshold values for centers with sufficient follow-up colonoscopy resources. More research is needed to precisely establish FIT thresholds for each sex and age subgroup.

PROTOCOL

PROSPERO CRD42017068760.

Incidence rates of cardiovascular outcomes in a community-based population of cancer patients

Background

There are limited data on the incidence of cardiovascular disease among cancer patients in the pre‐tyrosine kinase inhibitor (TKI) era. Such data are important in order to contextualize the incidence of various cardiovascular outcomes among cancer patients enrolled in clinical trials of new agents and for postmarketing surveillance.

Methods

A retrospective cohort study was conducted using data from the Kaiser Permanente Northern California (KPNC) population of cancer patients. The inclusion criterion was a KPNC Cancer Registry diagnosis of any of several selected solid and hematologic tumors between 1997 and 2009 not treated with a TKI. Endpoints were identified using ICD‐9 codes and included acute coronary syndrome, heart failure, stroke, cardiac arrest, hypertension, venous thromboembolism, all‐cause mortality, and cardiovascular mortality. Event rates were calculated according to type of cancer and number of cardiovascular risk factors.

Results

The study included almost 165 000 individuals with a broad variety of tumor types. The parent cohort was 54% female and 35% were ≥70 years old. Cardiovascular risk factors such as diabetes mellitus (14% of patients with solid tumors, 15% of patients with liquid tumors), dyslipidemia (33%, 31%), hypertension (50%, 49%), and smoking (35%, 32%) were common. The most frequent adverse outcomes were incident hypertension (26.8‐61.0 cases per 1000 person‐years, depending on the type of cancer), heart failure (9.4‐78.7), and acute coronary syndrome (2.6‐48.1). These event rates are high compared to what has been reported in prior KPNC cohort studies of patients without cancer. The rates of acute coronary syndrome, heart failure, and ischemic stroke increased with increasing numbers of cardiovascular risk factors.

Conclusions

In a population of patients with cancer not exposed to TKIs, cardiovascular risk factors and outcomes are very common, regardless of cancer type. These data can inform the evaluation of potential excess cardiovascular risks from new interventions.

Colorectal cancer screening with faecal immunochemical testing, sigmoidoscopy or colonoscopy: a clinical practice guideline

CLINICAL QUESTION

Recent 15-year updates of sigmoidoscopy screening trials provide new evidence on the effectiveness of colorectal cancer screening. Prompted by the new evidence, we asked: "Does colorectal cancer screening make an important difference to health outcomes in individuals initiating screening at age 50 to 79? And which screening option is best?"

CURRENT PRACTICE

Numerous guidelines recommend screening, but vary on recommended test, age and screening frequency. This guideline looks at the evidence and makes recommendations on screening for four screening options: faecal immunochemical test (FIT) every year, FIT every two years, a single sigmoidoscopy, or a single colonoscopy.

RECOMMENDATIONS

These recommendations apply to adults aged 50-79 years with no prior screening, no symptoms of colorectal cancer, and a life expectancy of at least 15 years. For individuals with an estimated 15-year colorectal cancer risk below 3%, we suggest no screening (weak recommendation). For individuals with an estimated 15-year risk above 3%, we suggest screening with one of the four screening options: FIT every year, FIT every two years, a single sigmoidoscopy, or a single colonoscopy (weak recommendation). With our guidance we publish the linked research, a graphic of the absolute harms and benefits, a clear description of how we reached our value judgments, and linked decision aids.

HOW THIS GUIDELINE WAS CREATED

A guideline panel including patients, clinicians, content experts and methodologists produced these recommendations using GRADE and in adherence with standards for trustworthy guidelines. A linked systematic review of colorectal cancer screening trials and microsimulation modelling were performed to inform the panel of 15-year screening benefits and harms. The panel also reviewed each screening option's practical issues and burdens. Based on their own experience, the panel estimated the magnitude of benefit typical members of the population would value to opt for screening and used the benefit thresholds to inform their recommendations.

THE EVIDENCE

Overall there was substantial uncertainty (low certainty evidence) regarding the 15-year benefits, burdens and harms of screening. Best estimates suggested that all four screening options resulted in similar colorectal cancer mortality reductions. FIT every two years may have little or no effect on cancer incidence over 15 years, while FIT every year, sigmoidoscopy, and colonoscopy may reduce cancer incidence, although for FIT the incidence reduction is small compared with sigmoidoscopy and colonoscopy. Screening related serious gastrointestinal and cardiovascular adverse events are rare. The magnitude of the benefits is dependent on the individual risk, while harms and burdens are less strongly associated with cancer risk.

UNDERSTANDING THE RECOMMENDATION

Based on benefits, harms, and burdens of screening, the panel inferred that most informed individuals with a 15-year risk of colorectal cancer of 3% or higher are likely to choose screening, and most individuals with a risk of below 3% are likely to decline screening. Given varying values and preferences, optimal care will require shared decision making.

No Association Between Vitamin D Status and Risk of Barrett's Esophagus or Esophageal Adenocarcinoma: A Mendelian Randomization Study

BACKGROUND & AIMS

Epidemiology studies of circulating concentrations of 25 hydroxy vitamin D (25(OH)D) and risk of esophageal adenocarcinoma (EAC) have produced conflicting results. We conducted a Mendelian randomization study to determine the associations between circulating concentrations of 25(OH)D and risks of EAC and its precursor, Barrett's esophagus (BE).

METHODS

We conducted a Mendelian randomization study using a 2-sample (summary data) approach. Six single-nucleotide polymorphisms (SNPs; rs3755967, rs10741657, rs12785878, rs10745742, rs8018720, and rs17216707) associated with circulating concentrations of 25(OH)D were used as instrumental variables. We collected data from 6167 patients with BE, 4112 patients with EAC, and 17,159 individuals without BE or EAC (controls) participating in the Barrett's and Esophageal Adenocarcinoma Consortium, as well as studies from Bonn, Germany, and Cambridge and Oxford, United Kingdom. Analyses were performed separately for BE and EAC.

RESULTS

Overall, we found no evidence for an association between genetically estimated 25(OH)D concentration and risk of BE or EAC. The odds ratio per 20 nmol/L increase in genetically estimated 25(OH)D concentration for BE risk estimated by combining the individual SNP association using inverse variance weighting was 1.21 (95% CI, 0.77-1.92; P = .41). The odds ratio for EAC risk, estimated by combining the individual SNP association using inverse variance weighting, was 0.68 (95% CI, 0.39-1.19; P = .18).

CONCLUSIONS

In a Mendelian randomization study, we found that low genetically estimated 25(OH)D concentrations were not associated with risk of BE or EAC.

Colonoscopy Indication Algorithm Performance Across Diverse Health Care Systems in the PROSPR Consortium

BACKGROUND

Despite the importance of characterizing colonoscopy indication for quality monitoring and cancer screening program evaluation, there is no standard approach to documenting colonoscopy indication in medical records.

METHODS

We applied two algorithms in three health care systems to assign colonoscopy indication to persons 50-89 years old who received a colonoscopy during 2010-2013. Both algorithms used standard procedure, diagnostic, and laboratory codes. One algorithm, the KPNC algorithm, used a hierarchical approach to classify exam indication into: diagnostic, surveillance, or screening; whereas the other, the SEARCH algorithm, used a logistic regression-based algorithm to provide the probability that colonoscopy was performed for screening. Gold standard assessment of indication was from medical records abstraction.

RESULTS

There were 1,796 colonoscopy exams included in analyses; age and racial/ethnic distributions of participants differed across health care systems. The KPNC algorithm's sensitivities and specificities for screening indication ranged from 0.78-0.82 and 0.78-0.91, respectively; sensitivities and specificities for diagnostic indication ranged from 0.78-0.89 and 0.74-0.82, respectively. The KPNC algorithm had poor sensitivities (ranging from 0.11-0.67) and high specificities for surveillance exams. The Area Under the Curve (AUC) of the SEARCH algorithm for screening indication ranged from 0.76-0.84 across health care systems. For screening indication, the KPNC algorithm obtained higher specificities than the SEARCH algorithm at the same sensitivity.

CONCLUSION

Despite standardized implementation of these indication algorithms across three health care systems, the capture of colonoscopy indication data was imperfect. Thus, we recommend that standard, systematic documentation of colonoscopy indication should be added to medical records to ensure efficient and accurate data capture.

Comparison of Universal Versus Age-Restricted Screening of Colorectal Tumors for Lynch Syndrome Using Mismatch Repair Immunohistochemistry: A Cohort Study

BACKGROUND

Guidelines recommend screening all patients with newly diagnosed colorectal cancer (CRC) for Lynch syndrome (LS). However, the efficiency of universal LS screening in elderly populations has not been well studied.

OBJECTIVE

To compare the performance of age-restricted and universal LS screening using reflex mismatch repair (MMR) immunohistochemistry (IHC) of CRC tumors.

DESIGN

Retrospective cohort study.

SETTING

A large, diverse, community-based health care system.

PARTICIPANTS

3891 persons with newly diagnosed CRC who had LS screening between 2011 and 2016.

MEASUREMENTS

Diagnostic yield of different LS screening strategies.

RESULTS

Sixty-three LS cases (diagnostic yield, 1.62%) were identified by universal screening, with only 5 (7.9%) detected after age 70 years and 1 (1.6%) detected after age 80 years. When all patients with CRC who had universal screening were used as the denominator, 58 LS cases (diagnostic yield, 1.49% [95% CI, 1.13% to 1.92%]) were identified in patients with CRC diagnosed at or before age 70 years, 60 LS cases (diagnostic yield, 1.54% [CI, 1.18% to 1.98%]) were identified in those with CRC diagnosed at or before age 75 years, and 62 LS cases (diagnostic yield, 1.59% [CI, 1.22% to 2.04%]) were identified in those with CRC diagnosed at or before age 80 years. Using 75 years as the upper age limit for screening missed 3 of 63 (4.8%) LS cases but resulted in 1053 (27.1%) fewer cases requiring tumor MMR IHC. Using 80 years as the upper age limit missed 1 of 63 (1.6%) LS cases and resulted in 668 (17.2%) fewer cases requiring tumor MMR IHC.

LIMITATION

Persons who were eligible for but did not complete germline analysis were excluded from calculations of performance characteristics.

CONCLUSION

The incremental diagnostic yield decreased substantially after age 70 to 75 years. Stopping reflex CRC screening for LS after age 80 years may be reasonable because of very low efficiency, particularly in resource-limited settings, but this merits further investigation. Studies evaluating the effect of diagnosing LS in elderly persons on their family members are needed.

PRIMARY FUNDING SOURCE

Kaiser Permanente Northern California Division of Research.

Time to Follow-up After Colorectal Cancer Screening by Health Insurance Type

INTRODUCTION

The purpose of this study was to test the hypothesis that patients with Medicaid insurance or Medicaid-like coverage would have longer times to follow-up and be less likely to complete colonoscopy compared with patients with commercial insurance within the same healthcare systems.

METHODS

A total of 35,009 patients aged 50-64years with a positive fecal immunochemical test were evaluated in Northern and Southern California Kaiser Permanente systems and in a North Texas safety-net system between 2011 and 2012. Kaplan-Meier estimation was used between 2016 and 2017 to calculate the probability of having follow-up colonoscopy by coverage type. Among Kaiser Permanente patients, Cox regression was used to estimate hazard ratios and 95% CIs for the association between coverage type and receipt of follow-up, adjusting for sociodemographics and health status.

RESULTS

Even within the same integrated system with organized follow-up, patients with Medicaid were 24% less likely to complete follow-up as those with commercial insurance. Percentage receiving colonoscopy within 3 months after a positive fecal immunochemical test was 74.6% for commercial insurance, 63.10% for Medicaid only, and 37.5% for patients served by the integrated safety-net system.

CONCLUSIONS

This study found that patients with Medicaid were less likely than those with commercial insurance to complete follow-up colonoscopy after a positive fecal immunochemical test and had longer average times to follow-up. With the future of coverage mechanisms uncertain, it is important and timely to assess influences of health insurance coverage on likelihood of follow-up colonoscopy and identify potential disparities in screening completion.

Collaborating on Data, Science, and Infrastructure: The 20-Year Journey of the Cancer Research Network

The Cancer Research Network (CRN) is a consortium of 12 research groups, each affiliated with a nonprofit integrated health care delivery system, that was first funded in 1998. The overall goal of the CRN is to support and facilitate collaborative cancer research within its component delivery systems. This paper describes the CRN's 20-year experience and evolution. The network combined its members' scientific capabilities and data resources to create an infrastructure that has ultimately supported over 275 projects. Insights about the strengths and limitations of electronic health data for research, approaches to optimizing multidisciplinary collaboration, and the role of a health services research infrastructure to complement traditional clinical trials and large observational datasets are described, along with recommendations for other research consortia.

Strategies to Improve Follow-up After Positive Fecal Immunochemical Tests in a Community-Based Setting: A Mixed-Methods Study

OBJECTIVES

The effectiveness of fecal immunochemical test (FIT) screening for colorectal cancer depends on timely colonoscopy follow-up of positive tests, although limited data exist regarding effective system-level strategies for improving follow-up rates.

METHODS

Using a mixed-methods design (qualitative and quantitative), we first identified system-level strategies that were implemented for improving timely follow-up after a positive FIT test in a large community-based setting between 2006 and 2016. We then evaluated changes in time to colonoscopy among FIT-positive patients across 3 periods during the study interval, controlling for screening participant age, sex, race/ethnicity, comorbidity, FIT date, and previous screening history.

RESULTS

Implemented strategies over the study period included setting a goal of colonoscopy follow-up within 30 days of a positive FIT, tracking FIT-positive patients, early telephone contact to directly schedule follow-up colonoscopies, assigning the responsibility for follow-up tracking and scheduling to gastroenterology departments (vs primary care), and increasing colonoscopy capacity. Among 160,051 patients who had a positive FIT between 2006 and 2016, 126,420 (79%) had a follow-up colonoscopy within 180 days, including 67% in 2006-2008, 79% in 2009-2012, and 83% in 2013-2016 (P < 0.001). Follow-up within 180 days in 2016 varied moderately across service areas, between 72% (95% CI 70-75) and 88% (95% CI 86-91), but there were no obvious differences in the pattern of strategies implemented in higher- vs lower-performing service areas.

CONCLUSIONS

The implementation of system-level strategies coincided with substantial improvements in timely colonoscopy follow-up after a positive FIT. Intervention studies are needed to identify the most effective strategies for promoting timely follow-up.

Long-term Risk of Colorectal Cancer and Related Deaths After a Colonoscopy With Normal Findings

Importance

Guidelines recommend a 10-year rescreening interval after a colonoscopy with normal findings (negative colonoscopy results), but evidence supporting this recommendation is limited.

Objective

To examine the long-term risks of colorectal cancer and colorectal cancer deaths after a negative colonoscopy result, in comparison with individuals unscreened, in a large, community-based setting.

Design, Setting, and Participants

A retrospective cohort study was conducted in an integrated health care delivery organization serving more than 4 million members across Northern California. A total of 1 251 318 average-risk screening-eligible patients (age 50-75 years) between January 1, 1998, and December 31, 2015, were included. The study was concluded on December 31, 2016.

Exposures

Screening was examined as a time-varying exposure; all participants contributed person-time unscreened until they were either screened or censored. If the screening received was a negative colonoscopy result, the participants contributed person-time in the negative colonoscopy results group until they were censored.

Main Outcomes and Measures

Using Cox proportional hazards regression models, the hazard ratios (HRs) for colorectal cancer and related deaths were calculated according to time since negative colonoscopy result (or since cohort entry for those unscreened). Hazard ratios were adjusted for age, sex, race/ethnicity, Charlson comorbidity score, and body mass index.

Results

Of the 1 251 318 patients, 613 692 were men (49.0%); mean age was 55.6 (7.0) years. Compared with the unscreened participants, those with a negative colonoscopy result had a reduced risk of colorectal cancer and related deaths throughout the more than 12-year follow-up period, and although reductions in risk were attenuated with increasing years of follow-up, there was a 46% lower risk of colorectal cancer (hazard ratio, 0.54; 95% CI, 0.31-0.94) and 88% lower risk of related deaths (hazard ratio, 0.12; 95% CI, 0.02-0.82) at the current guideline-recommended 10-year rescreening interval.

Conclusions and Relevance

A negative colonoscopy result in average-risk patients was associated with a lower risk of colorectal cancer and related deaths for more than 12 years after examination, compared with unscreened patients. Our study findings may be able to inform guidelines for rescreening after a negative colonoscopy result and future studies to evaluate the costs and benefits of earlier vs later rescreening intervals.

Modifiable Failures in the Colorectal Cancer Screening Process and Their Association With Risk of Death

BACKGROUND & AIMS

Colorectal cancer (CRC) deaths occur when patients do not receive screening or have inadequate follow-up of abnormal results or when the screening test fails. We have few data on the contribution of each to CRC-associated deaths or factors associated with these events.

METHODS

We performed a retrospective cohort study of patients in the Kaiser Permanente Northern and Southern California systems (55-90 years old) who died of CRC from 2006 through 2012 and had ≥5 years of enrollment before diagnosis. We compared data from patients with those from a matched cohort of cancer-free patients in the same system. Receipt, results, indications, and follow-up of CRC tests in the 10-year period before diagnosis were obtained from electronic databases and chart audits.

RESULTS

Of 1750 CRC deaths, 75.9% (n = 1328) occurred in patients who were not up to date in screening and 24.1% (n = 422) occurred in patients who were up to date. Failure to screen was associated with fewer visits to primary care physicians. Of 3486 cancer-free patients, 44.6% were up to date in their screening. Patients who were up to date in their screening had a lower risk of CRC death (odds ratio, 0.38; 95% confidence interval, 0.33-0.44). Failure to screen, or failure to screen at appropriate intervals, occurred in a 67.8% of patients who died of CRC vs 53.2% of cancer-free patients; failure to follow-up on abnormal results occurred in 8.1% of patients who died of CRC vs 2.2% of cancer-free patients. CRC death was associated with higher odds of failure to screen or failure to screen at appropriate intervals (odds ratio, 2.40; 95% confidence interval, 2.07-2.77) and failure to follow-up on abnormal results (odds ratio, 7.26; 95% confidence interval, 5.26-10.03).

CONCLUSIONS

Being up to date on screening substantially decreases the risk of CRC death. In 2 health care systems with high rates of screening, most people who died of CRC had failures in the screening process that could be rectified, such as failure to follow-up on abnormal findings; these significantly increased the risk for CRC death.

Cervical cancer screening research in the PROSPR I consortium: Rationale, methods and baseline findings from a US cohort

Little is known about the effect of evolving risk-based cervical cancer screening and management guidelines on United States (US) clinical practice and patient outcomes. We describe the National Cancer Institute's Population-based Research Optimizing Screening through Personalized Regimens (PROSPR I) consortium, methods and baseline findings from its cervical sites: Kaiser Permanente Washington, Kaiser Permanente Northern California, Kaiser Permanente Southern California, Parkland Health & Hospital System/University of Texas Southwestern (Parkland-UTSW) and New Mexico HPV Pap Registry housed by University of New Mexico (UNM-NMHPVPR). Across these diverse healthcare settings, we collected data on human papillomavirus (HPV) vaccinations, screening tests/results, diagnostic and treatment procedures/results and cancer diagnoses on nearly 4.7 million women aged 18-89 years from 2010 to 2014. We calculated baseline (2012 for UNM-NMHPVPR; 2010 for other sites) frequencies for sociodemographics, cervical cancer risk factors and key screening process measures for each site's cohort. Healthcare delivery settings, cervical cancer screening strategy, race/ethnicity and insurance status varied among sites. The proportion of women receiving a Pap test during the baseline year was similar across sites (26.1-36.1%). Most high-risk HPV tests were performed either reflexively or as cotests, and utilization pattern varied by site. Prevalence of colposcopy or biopsy was higher at Parkland-UTSW (3.6%) than other sites (1.3-1.4%). Incident cervical cancer was rare. HPV vaccination among age-eligible women not already immunized was modest across sites (0.1-7.2%). Cervical PROSPR I makes available high-quality, multilevel, longitudinal screening process data from a large and diverse cohort of women to evaluate and improve the effectiveness of US cervical cancer screening delivery.

Receipt of Colonoscopy Following Diagnosis of Advanced Adenomas: An Analysis within Integrated Healthcare Delivery Systems

BACKGROUND

To reduce colorectal cancer incidence and mortality, experts recommend surveillance colonoscopy 3 years after advanced adenoma removal. Little is known about adherence to that interval.

METHODS

We describe patterns of and factors associated with subsequent colonoscopy among persons with ≥3 adenomas and/or ≥1 adenoma with villous/tubulovillous histology in four U.S. integrated healthcare delivery systems. We report Kaplan-Meier estimators of the cumulative percentage of patients undergoing colonoscopy 6 months to 3.5 years after an index colonoscopy with high-risk findings. Combining data from three healthcare systems, we used multivariable logistic regression with inverse probability of censoring weights to estimate ORs and 95% confidence intervals (CI) for associations between patient characteristics and receipt of subsequent colonoscopy.

RESULTS

Among 6,909 persons with advanced adenomas, the percent receiving a subsequent colonoscopy 6 months to 3.5 years later ranged from 18.3% (95% CI: 11.7%-27.8%) to 59.5% (95% CI: 53.8%-65.2%) across healthcare systems. Differences remained significant in the multivariable model. Patients with ≥3 adenomas were more likely than those with 1 to 2 villous/tubulovillous adenomas to undergo subsequent colonoscopy. Subsequent colonoscopy was also more common for patients ages 60-74 and less common for patients ages 80 to 89 compared with those ages 50 to 54 years at their index colonoscopy. Sex, race/ethnicity, and comorbidity index score were generally not associated with subsequent colonoscopy receipt.

CONCLUSIONS

Colonoscopy within the recommended interval following advanced adenoma was underutilized and varied by healthcare system, age, and number of adenomas.

IMPACT

Strategies to improve adherence to surveillance colonoscopy following advanced adenomas are needed.

Effects of Organized Colorectal Cancer Screening on Cancer Incidence and Mortality in a Large Community-Based Population

BACKGROUND & AIMS

Little information is available on the effectiveness of organized colorectal cancer (CRC) screening on screening uptake, incidence, and mortality in community-based populations.

METHODS

We contrasted screening rates, age-adjusted annual CRC incidence, and incidence-based mortality rates before (baseline year 2000) and after (through 2015) implementation of organized screening outreach, from 2007 through 2008 (primarily annual fecal immunochemical testing and colonoscopy), in a large community-based population. Among screening-eligible individuals 51-75 years old, we calculated annual up-to-date status for cancer screening (by fecal test, sigmoidoscopy, or colonoscopy), CRC incidence, cancer stage distributions, and incidence-based mortality.

RESULTS

Initiation of organized CRC screening significantly increased the up-to-date status of screening, from 38.9% in 2000 to 82.7% in 2015 (P < .01). Higher rates of screening were associated with a 25.5% reduction in annual CRC incidence between 2000 and 2015, from 95.8 to 71.4 cases/100,000 (P < .01), and a 52.4% reduction in cancer mortality, from 30.9 to 14.7 deaths/100,000 (P < .01). Increased screening was initially associated with increased CRC incidence, due largely to greater detection of early-stage cancers, followed by decreases in cancer incidence. Advanced-stage CRC incidence rates decreased 36.2%, from 45.9 to 29.3 cases/100,000 (P < .01), and early-stage CRC incidence rates decreased 14.5%, from 48.2 to 41.2 cases/100,000 (P < .04).

CONCLUSIONS

Implementing an organized CRC screening program in a large community-based population rapidly increased screening participation to the ≥80% target set by national organizations. Screening rates were sustainable and associated with substantial decreases in CRC incidence and mortality within short time intervals, consistent with early detection and cancer prevention.

Influence of Varying Quantitative Fecal Immunochemical Test Positivity Thresholds on Colorectal Cancer Detection: A Community-Based Cohort Study

Background

The fecal immunochemical test (FIT) is commonly used for colorectal cancer (CRC) screening. Despite demographic variations in stool hemoglobin concentrations, few data exist regarding optimal positivity thresholds by age and sex.

Objective

To identify programmatic (multitest) FIT performance characteristics and optimal FIT quantitative hemoglobin positivity thresholds in a large, population-based, screening program.

Design

Retrospective cohort study.

Setting

Kaiser Permanente Northern and Southern California.

Participants

Adults aged 50 to 75 years who were eligible for screening and had baseline quantitative FIT results (2013 to 2014) and 2 years of follow-up. Nearly two thirds (411 241) had FIT screening in the previous 2 years.

Measurements

FIT programmatic sensitivity for CRC and number of positive test results per cancer case detected, overall and by age and sex.

Results

Of 640 859 persons who completed a baseline FIT and were followed for 2 years, 481 817 (75%) had at least 1 additional FIT and 1245 (0.19%) received a CRC diagnosis. Cancer detection (programmatic sensitivity) increased at lower positivity thresholds, from 822 in 1245 (66.0%) at 30 µg/g to 925 (74.3%) at 20 µg/g and 987 (79.3%) at 10 µg/g; the number of positive test results per cancer case detected increased from 43 at 30 µg/g to 52 at 20 µg/g and 85 at 10 µg/g. Reducing the positivity threshold from 20 to 15 µg/g would detect 3% more cancer cases and require 23% more colonoscopies. At the conventional FIT threshold of 20 µg/g, programmatic sensitivity decreased with increasing age (79.0%, 73.4%, and 68.9% for ages 50 to 59, 60 to 69, and 70 to 75 years, respectively; P = 0.009) and was higher in men than women (77.0% vs. 70.6%; P = 0.011).

Limitation

Information on advanced adenoma was lacking.

Conclusion

Increased cancer detection at lower positivity thresholds is counterbalanced by substantial increases in positive tests. Tailored thresholds may provide screening benefits that are more equal among different demographic groups, depending on local resources.

Primary Funding Source

National Cancer Institute.