A comparative analysis of risk factor associations with interval and screen-detected breast cancers: A large UK prospective study

The associations of certain factors, such as age and menopausal hormone therapy, with breast cancer risk are known to differ for interval and screen-detected cancers. However, the extent to which associations of other established breast cancer risk factors differ by mode of detection is unclear. We investigated associations of a wide range of risk factors using data from a large UK cohort with linkage to the National Health Service Breast Screening Programme, cancer registration, and other health records. We used Cox regression to estimate adjusted relative risks (RRs) and 95% confidence intervals (CIs) for associations between risk factors and breast cancer risk. A total of 9421 screen-detected and 5166 interval cancers were diagnosed in 517,555 women who were followed for an average of 9.72 years. We observed the following differences in risk factor associations by mode of detection: greater body mass index (BMI) was associated with a smaller increased risk of interval (RR per 5 unit increase 1.07, 95% CI 1.03-1.11) than screen-detected cancer (RR 1.27, 1.23-1.30); having a first-degree family history was associated with a greater increased risk of interval (RR 1.81, 1.68-1.95) than screen-detected cancer (RR 1.52, 1.43-1.61); and having had previous breast surgery was associated with a greater increased risk of interval (RR 1.85, 1.72-1.99) than screen-detected cancer (RR 1.34, 1.26-1.42). As these differences in associations were relatively unchanged after adjustment for tumour grade, and are in line with the effects of these factors on mammographic density, they are likely to reflect the effects of these risk factors on screening sensitivity.

Systematic review and meta-analysis of prognostic characteristics for breast cancers in populations with digital versus film mammography indicate the transition may have increased both early detection and overdiagnosis

OBJECTIVE

Film mammography has replaced digital mammography in breast screening programs globally. This led to a small increase in the rate of detection, but whether the detection of clinically important cancers increased is uncertain. We aimed to assess the impact on tumour characteristics of screen-detected and interval breast cancers.

STUDY DESIGN AND SETTING

We searched seven databases from inception to 08 October 2023 for publications comparing film and digital mammography within the same population of asymptomatic women at population (average) risk of breast cancer. We recorded reported tumour characteristics and assessed risk of bias using the ROBINS-I tool. We synthesized results using meta-analyses of random effects.

RESULTS

Eighteen studies were included in the analysis from 8 countries, including 11,592,225 screening examinations (8,117,781 film; 3,474,444 digital). There were no differences in tumour size, morphology, grade, node status, receptor status, or stage in the pooled differences for screen-detected and interval invasive cancer tumour characteristics. There were statistically significant increases in screen-detected DCIS across all grades: 0.05 (0.00-0.11), 0.14 (0.05-0.22), and 0.19 (0.05-0.33) per 1,000 screens for low, intermediate, and high grade DCIS respectively. There were similar (non-statistically significant) increases in screen-detected invasive cancer across all grades.

CONCLUSION

The increased detection of all grades of DCIS and invasive cancer may indicate both increased early detection of more aggressive disease and increased overdiagnosis.

FUNDING

Australian National Health and Medical Research Council and the National Breast Cancer Foundation.

REGISTRATION

PROSPERO 2017:CRD42017070601.

Proportions and characteristics of interval cancer in annual fecal immunochemical test screening and postcolonoscopy colorectal cancer: Results from a Japanese multicenter prospective study using questionnaires, the C-DETECT study

OBJECTIVES

There are several types of colorectal cancer (CRC) according to the detection methods and intervals, including interval CRC (iCRC) and postcolonoscopy CRC (PCCRC). We aimed to examine their proportions and characteristics.

METHODS

We conducted a multicenter prospective study using questionnaires in Japan ("C-DETECT study"), in which differences in CRC characteristics according to detection methods and intervals were examined from consecutive adult patients. Because the annual fecal immunochemical test (FIT) was used in population-based screening, the annual FIT-iCRC was assessed.

RESULTS

In total, 1241 CRC patients (1064 with invasive CRC) were included. Annual FIT-iCRC (a), 3-year PCCRC (b), and CRC detected within 1 year after a positive FIT with noncompliance to colonoscopy (c) accounted for 4.5%, 7.0%, and 3.9% of all CRCs, respectively, and for 3.9%, 5.4%, and 4.3% of invasive CRCs, respectively. The comparison among these (a, b, c) and other CRCs (d) demonstrated differences in the proportions of ≥T2 invasion ([a] 58.9%, [b] 44.8%, [c] 87.5%, [d] 73.0%), metastasis ([a] 33.9%, [b] 21.8%, [c] 54.2%, [d] 43.9%), right-sided CRC ([a] 42.9%, [b] 40.2%, [c] 18.8%, [d] 28.6%), and female sex ([a] 53.6%, [b] 49.4%, [c] 27.1%, [d] 41.6%). In metastatic CRC, (a) and (b) showed a higher proportions of BRAF mutations ([a] [b] 12.0%, [c] [d] 3.1%).

CONCLUSIONS

Annual FIT-iCRC and 3-year PCCRC existed in nonnegligible proportions. They were characterized by higher proportions of right-sided tumors, female sex, and BRAF mutations. These findings suggest that annual FIT-iCRC and 3-year PCCRC may have biological features different from those of other CRCs.

Interval cancer after two rounds of a Swedish population-based screening program using gender-specific cut-off levels in fecal immunochemical test

OBJECTIVE

To evaluate interval cancer (IC) after two screening rounds of the Swedish population-based screening program of Stockholm-Gotland applying gender-specific cut-off levels in the fecal immunochemical test (FIT).

METHODS

All 60- to 69-year-olds invited to screening 2015-2019 were included. The cut-off level for a positive test was 40 µg/g in women and 80 µg/g in men. Screening-detected colorectal cancers (SD CRCs) and ICs were verified in the Swedish Colorectal Cancer Register, and the follow-up time was two years from invitation. The test sensitivity, the IC rate (ICs per 10,000 screening negatives) and the IC incidence (ICs per 100,000 person-years) relative to the background CRC incidence were assessed by gender and age. The FIT levels were compared in men and women for CRCs diagnosed within one year of the sample.

RESULTS

In the second screening round, 229,187 were invited, and SD CRCs and ICs were diagnosed in 193 and 144, respectively. The IC rate was 8.9 (7.4-10.3) and test sensitivity 0.61 (0.55-0.66), and was similar in men and women. For two screening rounds, the IC rate was significantly higher in men than in women, but the IC incidence/ background CRC incidence was similar in both genders. The FIT levels in female participants with CRC were significantly lower overall, and in early-staged CRCs as compared to men, and proximal localization was more common in women. In multivariable analysis, FIT levels were significantly lower in proximal CRCs.

CONCLUSION

Over two rounds, the IC incidence relative to the background CRC incidence was similar in men and women supporting a gender-specific screening strategy. The results could be explained by lower FIT levels in women due to proximal CRC localization.

Impact of a scalable training program on the quality of colonoscopy performance and risk of postcolonoscopy colorectal cancer

BACKGROUND AND AIMS

Endoscopist adenoma detection rates (ADRs) vary widely and are associated with patients' risk of postcolonoscopy colorectal cancers (PCCRCs). However, few scalable physician-directed interventions demonstrably both improve ADR and reduce PCCRC risk.

METHODS

Among patients undergoing colonoscopy, we evaluated the influence of a scalable online training on individual-level ADRs and PCCRC risk. The intervention was a 30-minute, interactive, online training, developed using behavior change theory, to address factors that potentially impede detection of adenomas. Analyses included interrupted time series analyses for pretraining versus posttraining individual-physician ADR changes (adjusted for temporal trends) and Cox regression for associations between ADR changes and patients' PCCRC risk.

RESULTS

Across 21 endoscopy centers and all 86 eligible endoscopists, ADRs increased immediately by an absolute 3.13% (95% confidence interval [CI], 1.31-4.94) in the 3-month quarter after training compared with .58% per quarter (95% CI, .40-.77) and 0.33% per quarter (95% CI, .16-.49) in the 3-year pretraining and posttraining periods, respectively. Posttraining ADR increases were higher among endoscopists with pretraining ADRs below the median. Among 146,786 posttraining colonoscopies (all indications), each 1% absolute increase in screening ADR posttraining was associated with a 4% decrease in their patients' PCCRC risk (hazard ratio, .96; 95% CI, .93-.99). An ADR increase of ≥10% versus <1% was associated with a 55% reduced risk of PCCRC (hazard ratio, .45; 95% CI, .24-.82).

CONCLUSIONS

A scalable, online behavior change training intervention focused on modifiable factors was associated with significant and sustained improvements in ADR, particularly among endoscopists with lower ADRs. These ADR changes were associated with substantial reductions in their patients' risk of PCCRC.

Interval cancer audit and disclosure in breast screening programmes: An international survey

OBJECTIVE AND SETTING

Accurate monitoring of interval cancers is important both for quality improvement and education and is a key parameter of breast screening quality assurance. Issues in relation to communication regarding interval cervical cancer in the Irish cervical screening programme were found, prompting interval cancer process review in all cancer screening programmes. An international survey to examine international consensus on interval breast cancer audit processes was conducted to inform Irish processes.

METHODS

A survey of 24 international population-based breast screening programmes was done to determine which undertook audit of interval breast cancer; if yes, they were asked (1) how they undertake audit, (2) if they obtain individual consent for audit and inform women of audit results, and (3) if disclosure of audit results occurs.

RESULTS

Response was 71% (17/24). Of these, 71% (12/17) have a programmatic audit process to calculate the interval cancer rate (ICR). Of these, ten also carry out radiological reviews, three using a blinded review. Two inform patients that audit is taking place; two provide choice to be in the audit; nine state that routine screening consent covers audit. For two of the five that have an open disclosure policy for medical incidents, this policy applies to screening interval cancers. One other country/region has an open disclosure policy for category 3 interval cancers only. Five have legal protection for interval cancers arising in the screened population.

CONCLUSION

While consistency in providing aggregate programmatic audits exists, there is no consistent approach to individual interval cancer reviews or results disclosure.

The Impact of a Six-Year Existing Screening Programme Using the Faecal Immunochemical Test in Flanders (Belgium) on Colorectal Cancer Incidence, Mortality and Survival: A Population-Based Study

The faecal immunochemical test (FIT) has been increasingly used for organised colorectal cancer (CRC) screening. We assessed the impact of a six-year existing FIT screening programme in Flanders (Belgium) on CRC incidence, mortality and survival. The Flemish CRC screening programme started in 2013, targeting individuals aged 50-74 years. Joinpoint regression was used to investigate trends of age-standardised CRC incidence and mortality among individuals aged 50-79 years (2004-2019). Their 5-year relative survival was calculated using the Ederer II method. We found that FIT screening significantly reduced CRC incidence, especially that of advanced-stage CRCs (69.8/100,000 in 2012 vs. 51.1/100,000 in 2019), with a greater impact in men. Mortality started to decline in men two years after organised screening implementation (annual reduction of 9.3% after 2015 vs. 2.2% before 2015). The 5-year relative survival was significantly higher in screen-detected (93.8%) and lower in FIT non-participant CRCs (61.9%) vs. FIT interval cancers and CRCs in never-invited cases (67.6% and 66.7%, respectively). Organised FIT screening in Flanders clearly reduced CRC incidence (especially advanced-stage) and mortality (in men, but not yet in women). Survival is significantly better in screen-detected cases vs. CRCs in unscreened people. Our findings support the implementation of FIT organised screening and the continued effort to increase uptake.

Endoscopic surveillance of Lynch syndrome at a highly specialized center in Sweden: An observational study of interval colorectal cancer and individual risk factors

Introduction

Lynch syndrome (LS) is the most common hereditary cause of colorectal cancer (CRC). In order to detect CRCs amongst LS patients, regular colonoscopies are recommended. However, an international agreement on an optimal surveillance interval has not yet been reached. In addition, few studies have investigated factors that could potentially increase the CRC risk amongst LS patients.

Aims

The primary aim was to describe the frequency of CRCs detected during endoscopic surveillance and to estimate the interval from a clean colonoscopy to CRC detection amongst LS patients. The secondary aim was to investigate individual risk factors, including sex, LS genotype, smoking, aspirin use and body mass index (BMI), on CRC risk amongst patients that develop CRC before and during surveillance.

Material and methods

Clinical data and colonoscopy findings from 366 LS patients' 1437 surveillance colonoscopies were collected from medical records and patient protocols. Logistic regression and Fisher's exact test were used to investigate associations between individual risk factors and CRC development. Mann-Whitney U test was used to compare the distribution of TNM stages of CRC detected before surveillance and after index.

Results

CRC was detected in 80 patients before surveillance and in 28 patients during surveillance (10 at index and 18 after index). During the surveillance programme, CRC was detected within 24 months in 65% of the patients, and after 24 months within 35% of the patients. CRC was more common amongst men, previous and current smokers, and the odds of developing CRC also increased with an increasing BMI. CRCs were more often detected amongst MLH1 and MSH2 carriers during surveillance, compared to the other genotypes.

Conclusions

We found that 35% of the CRC cases detected during surveillance were found after 24 months. MLH1 and MSH2 carriers were at higher risk of developing CRC during surveillance. Additionally, men, current or previous smokers, and patients with a higher BMI were at higher risk of developing CRC. Currently, LS patients are recommended a "one-size-fits-all" surveillance program. The results support the development of a risk-score whereby individual risk factors should be taken into consideration when deciding on an optimal surveillance interval.

Considerations for Evaluating the Introduction of New Cancer Screening Technology: Use of Interval Cancers to Assess Potential Benefits and Harms

This framework focuses on the importance of the consideration of the downstream intermediate and long-term health outcomes when a change to a screening program is introduced. The authors present a methodology for utilising the relationship between screen-detected and interval cancer rates to infer the benefits and harms associated with a change to the program. A review of the previous use of these measures in the literature is presented. The framework presents other aspects to consider when utilizing this methodology, and builds upon an existing framework that helps researchers, clinicians, and policy makers to consider the impacts of changes to screening programs on health outcomes. It is hoped that this research will inform future evaluative studies to assess the benefits and harms of changes to screening programs.

A randomised controlled trial of digital breast tomosynthesis vs digital mammography as primary screening tests: Screening results over subsequent episodes of the Proteus Donna study

Proteus Donna is a randomised controlled trial aimed at prospectively evaluating screening with digital breast tomosynthesis (DBT), including interval cancer detection (ICD) and cancer detection (CD) in the analysis as a cumulative measure over subsequent screening episodes. Consenting women aged 46 to 68 attending the regional Breast Screening Service were randomly assigned to conventional digital mammography (DM, control arm) or DBT in addition to DM (DBT, study arm). At the subsequent round all participants underwent DM. Thirty-six months follow-up allowed for the identification of cancers detected in the subsequent screening and interscreening interval. Relative risk (RR) and 95% confidence interval (95% CI) were computed. Cumulative CD and Nelson-Aalen incidence were analysed over the follow-up period. Between 31 December 2014 and 31 December 2017, 43 022 women were randomised to DM and 30 844 to DBT. At baseline, CD was significantly higher (RR: 1.44, 95% CI: 1.21-1.71) in the study arm. ICD did not differ significantly between the two arms (RR: 0.92, 95% CI: 0.62-1.35). At subsequent screening with DM, the CD was lower (nearly significant) in the study arm (RR: 0.83, 95% CI: 0.65-1.06). Over the follow-up period, the cumulative CD (comprehensive of ICD) was slightly higher in the study arm (RR: 1.15, 95% CI: 1.01-1.31). The Nelson-Aalen cumulative incidence over time remained significantly higher in the study arm for approximately 24 months. Benign lesions detection was higher in the study arm at baseline and lower at subsequent tests. Outcomes are consistent with a lead time gain of DBT compared to DM, with an increase in false positives and moderate overdiagnosis.

Association between antibiotic consumption and colon and rectal cancer development in older individuals: A territory-wide study

Background

Antibiotics may alter colorectal cancer (CRC) risk due to gut dysbiosis. We aimed to study the specific and temporal effects of various antibiotics on CRC development in older individuals.

Methods

This was a territory‐wide retrospective cohort study. Subjects aged 60 years and older who did not have CRC diagnosed on screening/diagnostic colonoscopy diagnosed between 2005 and 2013 were recruited. Exclusion criteria were history of CRC, colectomy, inflammatory bowel disease, and CRC diagnosed within 6 months of index colonoscopy. Exposure was use of any antibiotics up to 5 years before colonoscopy. The primary outcomes were CRC diagnosed >6 m after colonoscopy. Covariates were patient demographics, history of colonic polyps/polypectomy, concomitant medication use (NSAIDs, COX‐2 inhibitors, aspirin, and statins), and performance of endoscopy centers (colonoscopy volume and polypectomy rate). Stratified analysis was conducted according to nature of antibiotics and location of cancer.

Results

Ninety seven thousand one hundred and sixty‐two eligible subjects (with 1026 [1.0%] cases of CRC) were identified, 58,704 (60.4%) of whom were exposed to antibiotics before index colonoscopy. Use of antibiotics was associated with a lower risk of cancer in rectum (adjusted hazard ratio [aHR]: 0.64, 95% CI: 0.54–0.76), but a higher risk of cancer in proximal colon (aHR: 1.63, 95%CI: 1.15–2.32). These effects differed as regards the anti‐anaerobic/anti‐aerobic activity, narrow‐/broad‐spectrum, and administration route of antibiotics.

Conclusions

Antibiotics had divergent effects on CRC development in older subjects, which varied according to the location of cancer, antibiotic class, and administration route.

Interval cancers in a population-based screening program for colorectal cancer with gender-specific cut-off levels for fecal immunochemical test

Objective

To evaluate interval cancers (IC) in the population-based Swedish regional colorectal cancer (CRC) screening program of Stockholm-Gotland, which uses gender-specific cut-off levels for the fecal immunochemical test (FIT).

Methods

All individuals aged 60–69 in Stockholm-Gotland invited to the screening program in October 2015 to September 2017 were followed up 2 years after invitation. Cut-off level for a positive FIT was 40 µg/g in women and 80 µg/g in men. Those with a positive FIT were referred to colonoscopy. Screening-detected CRC (SD-CRC) and IC after negative FIT (FIT-IC) or negative screening colonoscopy (Colonoscopy-IC) were identified in the Swedish colorectal cancer register. The IC rate was calculated as IC/(FIT negatives + negative screening colonoscopies). The IC incidence rate (ICs among negatives per 100,000 person-years) in different sex and age groups was compared to the mean CRC incidence before regional screening implementation. Test sensitivity was defined as SD-CRC/(SD-CRC + FIT-IC).

Results

Approximately 214,400 individuals were invited, and in 3521 screening colonoscopies 257(6.3%) SD-CRCs were detected. During follow-up, 124 FIT-IC and 7 Colonoscopy-IC were diagnosed, yielding an IC rate of 12.6 and 6.0 per 10,000 negatives (p = 0.00005) and a test sensitivity of 62% and 75% (p = 0.01) in men and women respectively. The IC incidence rate compared to CRC incidence was non-significantly lower in women.

Conclusion

In the population-based screening program of Stockholm-Gotland with a cut-off of 40 µg/g in women and 80 µg/g in men, the test sensitivity was higher and the IC rate was lower in women, which might imply lowering the cut-off level in men. However, the IC incidence rate relative to the CRC incidence was similar in both genders.

Association of Regular Endoscopic Screening with Interval Gastric Cancer Incidence in the National Cancer Screening Program

Although regular endoscopic screening may help in early detection of gastric cancer, interval cancer remains a problem in the screening program. This study evaluated the association between regular endoscopic screening and interval cancer detection in the Korean National Cancer Screening Program (KNCSP). We defined three groups (regularly, irregularly, and not screened) according to the screening interval, and the trends in the interval cancer rate (ICR) between the groups were tested using the Cochran-Armitage test. The influence of regular endoscopic screening on the risk of interval cancer was evaluated using multivariable logistic regression. Among the 11,642,410 participants who underwent endoscopy, the overall ICR was 0.36 per 1000 negative screenings. The ICR of the not screened group (0.41) was the highest among the three groups and the risk of interval cancer in this group was 1.68 times higher (p < 0.001) than that in the regularly screened group. Women in their 40s who had regular screening with no history of intestinal metaplasia and gastric polyps would have the lowest probability of having interval cancer (0.005%). Regular participation in endoscopic screening programs for reducing the risk of interval cancer may help to improve the quality of screening programs.

Interval cancer audit and disclosure in cervical screening programmes: An international survey

BACKGROUND

Legal cases involving the National Cervical Screening Programme in Ireland following non-disclosure of an interval cervical cancer audit prompted this first international comparative survey of interval cervical cancer audit.

METHODS

A survey of 22 international population-based cervical screening programmes was conducted, to determine if they undertook audit of invasive cervical cancers. Those countries/regions that perform reviews were asked (i) how the audit was undertaken, including how the reviews were performed and how they controlled for retrospective bias, (ii) how women are informed of the audit process and how their consent is obtained, and (iii) how audit results were disclosed to patients.

RESULTS

Seventeen countries/regions invited completed the survey (77%); 65% (11/17) have an audit process for interval cervical cancers. Five perform individual patient reviews; three perform programme-wide review, with calculation of interval cancer detection rates; one routinely performs programme-wide review with calculation of interval cancer detection rates and offers individual reviews, and one routinely performs local hospital-level reviews. In the remaining country/region, hospital laboratories audit cancers, with a national audit process for all cervical cancers. Varying methodologies for retrospective cytology review were employed; four include control samples, with a ratio varying from 1:1 to 1:2. Three conduct a blinded review. Most countries/regions do not discuss interval cancer audit with participants and 3/11 (27.3%) inform women when a cervical cancer audit takes place. Disclosure is limited and variable.

CONCLUSION

The responses suggest that there is no consistent approach to audit of interval cervical cancers or to disclosure of audit results.

Risk of post colonoscopy colorectal cancer following screening colonoscopy with low-risk or no adenomas: A population-based study

AIM

In the Danish faecal occult blood test based bowel cancer screening programme, the first round was rolled out over 4 years. After roll-out, the planned faecal test recall procedure for individuals with either no or low risk adenomas at colonoscopy is 8 and 2 years, respectively. Here, we aimed to investigate the post colonoscopy colorectal cancer incidence in these two groups.

METHODS

All Danish screening individuals from 2014 to 2015 with a positive faecal test and either no or low risk adenomas at colonoscopy were included and followed for 3 years post screening for the event of colorectal cancer through national registries.

RESULTS

Out of 533,023 submitted faecal tests and 36,673 positive tests, 17,627 had no or low risk adenomas. We identified 60 (0.34%) individuals diagnosed with colorectal cancer within 3 years, 18 (0.29%) in the low risk adenoma group, and 42 (0.37%) in the no adenomas group (p = 0.44). Advancing age (HR = 1.079, p < 0.001) and higher faecal test value (HR = 1.001, p = 0.002) increased hazard of colorectal cancer occurrence, whereas male sex (HR = 1.3, p = 0.308) and having low risk adenomas (HR = 0.729, p = 0.264) did not.

CONCLUSION

We found no difference in post colonoscopy colorectal cancer occurrence between individuals with either no or low risk adenomas. Instead, advancing age and increased faecal test value was associated with a higher risk of post colonoscopy colorectal cancer.

Analysis of Post-Colonoscopy Colorectal Cancer and Its Subtypes in a Screening Programme

Using the algorithm of the World Endoscopy Organisation (WEO), we have studied retrospectively all colorectal cancers, both detected and non-detected by the Basque Country screening programme from 2009 to 2017. In the screening programme 61,335 colonoscopies were performed following a positive Faecal Immunochemical test (FIT) (≥20 µg Hb/g faeces) and the 128 cases of post-colonoscopy colorectal cancer (PCCRC) detected were analysed. Among them, 50 interval type PCCRCs were diagnosed (before the recommended surveillance), 0.8 cases per 1000 colonoscopies performed, and 78 non-interval type PCCRCs (in the surveillance carried out at the recommended time or delayed), 1.3 per 1000 colonoscopies. Among the non-interval type PCCRCs, 61 cases were detected in the surveillance carried out at the recommended time (type A) and 17 when the surveillance was delayed (type B), 1 case per 1000 colonoscopies performed and 0.28 cases per 1000 colonoscopies performed, respectively. Interval type PCCRC is less frequent than non-interval type PCCRC. In interval type PCCRCs, CRCs detected in advanced stages (stages III-IV) were significantly more frequent than those detected in early stages, compared to those of non-interval type PCCRCs (OR = 3.057; 95% CI, 1.410-6.625; p < 0.005). Non-interval type B PCCRCs are less frequent than non-interval type A PCCRCs, but the frequency of advanced stages is higher in interval type B PCCRCs.

Breast Density and Risk of Interval Cancers: The Effect of Annual Versus Biennial Screening Mammography Policies in Canada

Regular screening mammography reduces breast cancer mortality. However, in women with dense breasts, the performance of screening mammography is reduced, which is reflected in higher interval cancer rates (ICR). In Canada, population-based screening mammography programs generally screen women biennially; however, some provinces and territories offer annual mammography for women with dense breast tissue routinely and/or on recommendation of the radiologist. This study compared the ICRs in those breast screening programs with a policy of annual vs. those with biennial screening for women with dense breasts. Among 148,575 women with dense breasts screened between 2008 to 2010, there were 288 invasive interval breast cancers; screening programs with policies offering annual screening for women with dense breasts had fewer interval cancers 63/70,814 (ICR 0.89/1000, 95% CI: 0.67-1.11) compared with those with policies of usual biennial screening 225/77,761 (ICR 1.45 /1000 (annualized), 95% CI: 1.19-1.72) i.e. 63% higher (p = 0.0016). In screening programs where radiologists' screening recommendations were able to be analyzed, a total of 76,103 women were screened, with 87 interval cancers; the ICR was lower for recommended annual (65/69,650, ICR 0.93/1000, 95% CI: 0.71, 1.16) versus recommended biennial screening (22/6,453, ICR 1.70/1000 (annualized), 95%CI: 0.70, 2.71)(p = 0.0605). Screening program policies of annual as compared with biennial screening in women with dense breasts had the greatest impact on reducing interval cancer rates. We review our results in the context of current dense breast notification in Canada.

Possible Earlier Diagnosis of Ulcerative Colitis-Associated Neoplasia: A Retrospective Analysis of Interval Cases during Surveillance

Background: Early detection of ulcerative colitis-associated neoplasia (UCAN) is often difficult. The aim of this study was to clarify the morphology of initial UCAN. Methods: White-light colonoscopy images obtained within the 2 years before UCAN diagnosis were retrospectively reviewed. The primary endpoint was the frequency of visible or invisible neoplasia on the endoscopic images before UCAN diagnosis. The secondary endpoints were comparisons of (1) visible or invisible neoplasia on initial endoscopic images of early-stage and advanced cancers, (2) the clinical backgrounds of patients in whom neoplasia was visible or invisible on initial endoscopic images, and (3) the clinical backgrounds of patients with distinct and indistinct UCAN borders. Results: Of the 27 UCAN lesions (11 early-stage; 16 advanced-stage), 25.9% (n = 7) were initially visible and 74.1% (n = 20) were invisible. The mean interval between the last surveillance colonoscopy and UCAN diagnosis was 14.5 ± 6.7 months. Of early-stage cancers, 18.2% (n = 2) were visible and 81.8% (n = 9) were invisible. Of advanced-stage cancers, 31.3% (n = 5) were visible and 68.8% (n = 11) were invisible. Invisible lesions were significantly more common in the rectum (p = 0.011) and tended to be more common in patients with inflammation and left-sided colitis (p = 0.084, p = 0.068, respectively). Patients with indistinct UCAN borders were significantly more likely to present with inflammation than those with distinct UCAN borders (p = 0.021). Conclusion: More careful surveillance is needed because rectum lesions and inflammation are difficult to identify as neoplasia even within the 2 years before a UCAN diagnosis.

Which type of cancer is detected in breast screening programs? Review of the literature with focus on the most frequent histological features

Breast cancer is the most frequent type of cancer affecting female patients. The introduction of breast cancer screening programs led to a substantial reduction of mortality from breast cancer. Nevertheless, doubts are being raised on the real efficacy of breast screening programs. The aim of the present paper is to review the main pathological type of cancers detected in breast cancer screening programs. Specifically, attention will be given to: in situ carcinoma, invasive carcinoma histotypes and interval cancer.

Breast Cancer Screening in Asian Women with Dense Breast by Mammography: A Cross-Sectional Observational Study

Objective:

Mammography density of Asian women is known to be higher than Western women. After 2009, the Korean National Cancer Screening Program (NCSP) has started to notify mammography density (MD). To investigate the effect of MD notification, we integrated screening results with national health insurance claim data from 2009 to 2013.

Patients and Methods:

We performed a cross-sectional observational study which investigated the crude detection rate (CDR), positive predictive value (PPV), and incidence rate of Interval Cancer (IC). IC was defined as breast cancer, where the interval between the screening date and date of diagnosis was more than 12 months and less than 24 months among participants with previous normal results.

Results:

CDR and PPV per 100,000 results increased from 510.9 to 756.2 and from 1842.5 to 3364.9, respectively. The incidence rate of IC per 100,000 negative results increased from 623.3 to 676.2. Women younger than 50 years had a high incidence of ICs.

Conclusion:

After notifying MD, the incidence rate of IC less increased comparing with CDR or PPV. Screening mammography could be more useful to Asian women when reporting MD.

Classifying interval cancers as false negatives or newly occurring in fecal immunochemical testing

OBJECTIVE

To classify interval colorectal cancers as false negatives or newly occurring cases in a biennial Fecal immunochemical test (FIT) screening program and by various interscreening intervals.

SETTING

Data from the Taiwanese biennial colorectal cancer screening program involving FIT from 2004 to 2014 were used to estimate the incidence rate of asymptomatic colorectal cancer and the rate of its subsequent progression to clinical mode.

METHODS

The sensitivity of detecting asymptomatic colorectal cancers excluding newly developed colorectal cancers was compared to the conventional estimate of sensitivity, the complementary FIT interval cancer rate as a percentage of the expected incidence rate ((1-I/E)%). The relative contribution of newly developed or false-negative cases to FIT interval colorectal cancers was estimated by age and interscreening intervals.

RESULTS

The Taiwanese biennial fecal immunochemical test screening program had a conventional sensitivity estimate of 70.2%. After newly developed colorectal cancers were separated from FIT interval cancers, the ability to detect asymptomatic colorectal cancers increased to 75.5%. FIT interval colorectal cancers from the biennial program mainly resulted from newly developed colorectal cancers (68.8%). The corresponding figures decreased to 61.1% for the annual program but increased to 74.7% for the triennial program. The preponderance of newly developed colorectal cancers among FIT interval cancers was more prominent in screenees aged 50-59  than in those aged 60-69.

CONCLUSIONS

Newly developed colorectal cancers showed a predominance among the FIT interval colorectal cancers in particular in the younger population screened. It is desirable to identify high-risk individuals to offer them a short interscreening interval or advanced detection methods to reduce their odds of developing interval cancer.

Retrospective analysis of the effect on interval cancer rate of adding an artificial intelligence algorithm to the reading process for two-dimensional full-field digital mammography

Interval cancers are a commonly seen problem in organized breast cancer screening programs and their rate is measured for quality assurance. Artificial intelligence algorithms have been proposed to improve mammography sensitivity, in which case it is likely that the interval cancer rate would decrease and the quality of the screening system could be improved. Interval cancers from negative screening in 2011 and 2012 of one regional unit of the national German breast cancer screening program were classified by a group of radiologists, categorizing the screening digital mammography with diagnostic images as true interval, minimal signs, false negative and occult cancer. Screening mammograms were processed using a detection algorithm based on deep learning. Of the 29 cancer cases available, artificial intelligence identified eight out of nine of those classified as minimal signs, all six false negatives and none of the true interval and occult cancers. Sensitivity for lesions judged to be already present in screening mammogram was 93% (95% confidence interval 68-100) and sensitivity for any interval cancer was 48% (95% confidence interval 29-67). Using an artificial intelligence algorithm as an additional reading tool has the potential to reduce interval cancers. How and if this theoretical advantage can be reached without a negative effect on recall rate is a challenge for future research.

Sensitivity and missed cancer rate in the symptomatic breast clinic-A retrospective cohort study of 40 323 patients

INTRODUCTION

Symptomatic presentations account for the majority of invasive breast cancer diagnoses. While the National Health Service Breast Screening Programme is subjected to strict quality control, no such system for performance monitoring exists in the symptomatic clinic. We assess the sensitivity of cancer detection and missed cancer rate for symptomatic breast patients to benchmark future outcome measures.

METHODS

A retrospective cohort study of patients attending the symptomatic breast clinic between October 2013 and October 2018 was performed. Patients with new cancer diagnoses were identified and screened for those who had presented to the department within the 3 years prior to their diagnosis. From this, the sensitivity and missed cancer rate were calculated.

RESULTS

About 40 323 patients were seen over the 5-year study period. About 2155 new cancers were diagnosed, with 2033 identified at their initial clinic attendance. A further 122 patients had cancer diagnosed on a subsequent appointment, of which 23 patients were considered to have had a delay in diagnosis. The sensitivity of the one-stop symptomatic breast clinic was therefore 99.0%, and the missed cancer rate was 0.06% over 5 years.

CONCLUSION

The missed cancer rate reported in this study is favorable compared to the outcomes reported in the National Health Service Breast Screening Programme and superior to the only other study reporting outcomes on a much smaller cohort. The unit in question therefore is performing exceptionally against current standards and sets a benchmark against which future performance can be measured.

Colorectal adenocarcinomas diagnosed following a negative faecal immunochemical test show high-risk pathological features in a colon screening programme

AIMS

The faecal immunochemical test (FIT) is used every 2 years to screen average-risk British Columbians aged 50-74 years, with follow-up colonoscopy for positive results. Non-screen-detected colorectal adenocarcinomas are defined as those detected within 25 months following a negative FIT. We aimed to more clearly characterise these malignancies.

METHODS AND RESULTS

A medical chart and focused pathology review of colorectal malignancies from 926 individuals who completed FIT in the British Columbia Colon Screening Program in 2014, and whose pathology reports were available for review, was conducted. This cohort was divided into two groups: individuals with colorectal adenocarcinomas diagnosed following a positive FIT (screen-detected) and individuals with colorectal adenocarcinoma diagnosed within 25 months of a negative FIT (FIT-interval cancers). Rates of clinically relevant pathological parameters, as outlined in the American Joint Committee on Cancer (AJCC), 8th edition, were compared between the screen-detected and FIT-interval cancer groups. A total of 876 screen-detected and 50 FIT-interval cancers were identified. FIT-interval cancers exhibited higher rates of high-grade differentiation (including poorly differentiated and undifferentiated cases; P < 0.01) and aggressive histotype (signet ring cell and mucinous carcinomas; P < 0.01) than did screen-detected cancers after Bonferroni correction. Colorectal adenocarcinoma diagnosed after a negative FIT may therefore be associated with worse prognostic determinants than screen-detected cancers.

CONCLUSION

FIT-interval cancers are associated with high-risk pathological features; the possibility that more aggressive, fast-growing lesions which arise in the interval after truly negative FITs cannot be ruled out. Further study of a larger cohort of FIT-interval cancers controlling for interaction among the different pathologic parameters will be undertaken.

Sudden PSA rise to ≥20 ng/ml and prostate cancer diagnosis in the United States: A population-based study

PURPOSE

While prostate-specific antigen (PSA) screening protocols vary, many clinicians have anecdotes of screened men with low PSA levels that rise significantly and are associated with high-risk prostate cancer (PC). We sought to better understand the frequency of high-risk cases that appear suddenly in a screened population.

METHODS

We utilized data from a Commercial and Medicare advantage claims database to identify all US men ages 50 and above undergoing PSA screening who then had a sudden interval rise in PSA (e.g., PSA ≥ 20) and diagnosis of PC. We determined associations with age, race, screening intensity, and baseline PSA levels.

RESULTS

In all, 526,120 men met entry criteria with an average age of 60.7 and follow-up of 5.6 years. As the baseline PSA increased, the rate of high-risk PC increased from 2/10,000 persons among men with the lowest baseline PSA (<1 ng/ml) to 14/10,000 person-years among men with a baseline PSA < 5 ng/ml. Moreover, as a man's age at baseline PSA increased, the rate of high-risk PC also increased. In contrast, the incidence of high-risk PC did not vary significantly by race/ethnicity. More screening PSAs and shorter intervals between PSA screenings were associated with a lower incidence of high-risk PC.

CONCLUSIONS

The incidence of high-risk PC in a screened population is low (<0.1%). Our findings suggest that systematic screening cannot eliminate all PC deaths and provide an estimate for the risk of the rapid development of high-risk cancers that is comparable to that observed in active surveillance populations.

Serrated lesions of the colon and rectum: Emergent epidemiological data and molecular pathways

In 2010, serrated polyps (SP) of the colon have been included in the WHO classification of digestive tumors. Since then a large corpus of evidence focusing on these lesions are available in the literature. This review aims to analyze the present data on the epidemiological and molecular aspects of SP. Hyperplastic polyps (HPs) are the most common subtype of SP (70–90%), with a minimal or null risk of malignant transformation, contrarily to sessile serrated lesions (SSLs) and traditional serrated adenomas (TSAs), which represent 10–20% and 1% of adenomas, respectively. The malignant transformation, when occurs, is supported by a specific genetic pathway, known as the serrated-neoplasia pathway. The time needed for malignant transformation is not known, but it may occur rapidly in some lesions. Current evidence suggests that a detection rate of SP ≥15% should be expected in a population undergoing screening colonoscopy. There are no differences between primary colonoscopies and those carried out after positive occult fecal blood tests, as this screening test fails to identify SP, which rarely bleed. Genetic similarities between SP and interval cancers suggest that these cancers could arise from missed SP. Hence, the detection rate of serrated-lesions should be evaluated as a quality indicator of colonoscopy. There is a lack of high-quality longitudinal studies analyzing the long-term risk of developing colorectal cancer (CRC), as well as the cancer risk factors and molecular tissue biomarkers. Further studies are needed to define an evidence-based surveillance program after the removal of SP, which is currently suggested based on experts’ opinions.

Incidence of interval breast cancer among women aged 45-49 in an organised mammography screening setting

OBJECTIVE

To estimate the proportional incidence (PI) of first- and second-year interval breast cancer among women aged 45-49.

METHODS

In the Emilia-Romagna Region (northern Italy), women aged 45-49 are invited to mammography screening annually, and women aged 50-74 biennially. For younger ones, the proportional incidence of interval cancer in the first and unique interval year was calculated using standard methods. For the second, hypothetical year, it was estimated using two different estimates of the ratio between the second- and the first-year proportional incidence observed among women aged 50-54. Overall, 567,151 negative mammography records were used.

RESULTS

In the first interval year, the observed proportional incidence of interval cancer among women aged 45-49 was 0.27 (95% confidence interval (CI), 0.22-0.33), within the European limit considered desirable for women aged 50-69 (<0.30). In the second, hypothetical interval year, the estimated proportional incidence ranged from 0.61 (95% CI, 0.43-0.86) to 0.48 (95% CI, 0.31-0.76) depending on whether the estimate was based on data from the pre-digital or digital era, respectively.

CONCLUSION

The more up-to-date estimate of 0.48, slightly below the maximum limit considered acceptable for women aged 50-69 (<0.50), suggests that a screening interval of two years may also be an acceptable option for women aged 45-49.

Precision Science on Incidence and Progression of Early-Detected Small Breast Invasive Cancers by Mammographic Features

The aim was to evaluate how the inter-screening interval affected the performance of screening by mammographic appearances. This was a Swedish retrospective screening cohort study with information on screening history and mammography features in two periods (1977–1985 and 1996–2010). The pre-clinical incidence and the mean sojourn time (MST) for small breast cancer allowing for sensitivity by mammographic appearances were estimated. The percentage of interval cancer against background incidence (I/E ratio) was used to assess the performance of mammography screening by different inter-screening intervals. The sensitivity-adjusted MSTs (in years) were heterogeneous with mammographic features, being longer for powdery and crushed stone-like calcifications (4.26, (95% CI, 3.50–5.26)) and stellate masses (3.76, (95% CI, 3.15–4.53)) but shorter for circular masses (2.65, (95% CI, 2.06–3.55)) in 1996–2010. The similar trends, albeit longer MSTs, were also noted in 1977–1985. The I/E ratios for the stellate type were 23% and 32% for biennial and triennial screening, respectively. The corresponding figures were 32% and 43% for the circular type and 21% and 29% for powdery and crushed stone-like calcifications, respectively. Mammography-featured progressions of small invasive breast cancer provides a new insight into personalized quality assurance, surveillance, treatment and therapy of early-detected breast cancer.

Interval colorectal cancers after negative faecal immunochemical test in a 13-year screening programme

OBJECTIVE

To assess faecal immunochemical test sensitivity for cancer in a very large population-based cohort followed up for six rounds with biennial faecal immunochemical test repetition.

METHODS

This study is based on interval colorectal cancers diagnosed in a cohort of subjects aged 50-69 undergoing repeated faecal immunochemical test screening (six rounds) from 2002 to 2015. Test sensitivity was calculated using both the Proportional Interval Cancer Rate and the Interval Cancer Proportion method.

RESULTS

Among 441,647 faecal immunochemical tests (123,347 individuals), 150 interval colorectal cancers were detected after a negative faecal immunochemical test. Interval colorectal cancer incidence rate was 1.87 per 10,000 person-years (95%CI: 1.60-2.20), and it was higher during the second interval year (rate ratio: 1.78; 95%CI: 1.28-2.47), for proximal locations (rate ratio: 3.00; 95%CI: 1.92-4.68), and among 60-71 year old subjects (rate ratio: 2.37; 95%CI: 1.61-3.50). The Proportional Interval Cancer Rate was 13.1%, with an overall faecal immunochemical test sensitivity of 86.9% (95%CI: 84.7-89.0). Sensitivity was lowest at the first round (81.5%; 95%CI: 75.6-86.2), and increased to 91.9% (95%CI: 83.9-96.5) for subsequent rounds. Applying the Interval Cancer Proportion method, sensitivity was 83.9% (95%CI: 81.3-86.2), and it was highest at the first round (89.0%; 95%CI: 85.7-91.6), ranging between 73% and 83.1% at subsequent rounds.

CONCLUSIONS

A faecal immunochemical test sensitivity for cancer higher than 80% resulted in a low incidence of interval colorectal cancers, representing an accurate estimate of one of the major limits of screening programmes. Due to intrinsic biases, the Proportional Interval Cancer Rate and the Interval Cancer Proportion methods generated different trends in faecal immunochemical test sensitivity by screening round.

Nonsteroidal anti-inflammatory drugs but not aspirin are associated with a lower risk of post-colonoscopy colorectal cancer

BACKGROUND

Although nonsteroidal anti-inflammatory drugs (NSAIDs) reduce colorectal cancer (CRC) risk, their role in preventing post-colonoscopy CRC (PCCRC) remains undetermined.

AIMS

To investigate whether NSAIDs reduce PCCRC risk after a negative baseline colonoscopy METHODS: This is a retrospective cohort study based on a territory-wide healthcare database of Hong Kong. All patients (aged 40 or above) who underwent colonoscopies between 2005 and 2013 were identified. Exclusion criteria included CRC detected within 6 months of index colonoscopy, prior CRC, inflammatory bowel disease and prior colectomy. The primary outcome was PCCRC-3y diagnosed between 6 and 36 months after index colonoscopy. Sites of CRC were categorised as proximal (proximal to splenic flexure) and distal. The adjusted hazards ratio (aHR) of PCCRC-3y with NSAID and aspirin use (defined as cumulative use for ≥90 days within 5 years before index colonoscopy) was derived by propensity score (PS) regression adjustment of 22 covariates (including patient factors, concurrent medication use and endoscopy centre's performance).

RESULTS

Of 187 897 eligible patients, 21 757 (11.6%) were NSAID users. 854 (0.45%) developed PCCRC-3y (proximal cancer: 147 [17.2%]). NSAIDs were associated with a lower PCCRC-3y risk (aHR: 0.54, 95% CI: 0.41-0.70), but not CRC that developed >3 years (aHR: 0.78, 95% CI 0.56-1.09). The aHR was 0.48 (95% CI: 0.24-0.95) for proximal and 0.55 (95% CI: 0.40-0.74) for distal cancer. A duration- and frequency response relationship was observed (P_trend  < 0.001). For aspirin, the aHR was 1.01 (95% CI: 0.80-1.28).

CONCLUSIONS

Non-aspirin NSAIDs were associated with lower PCCRC risk after a negative baseline colonoscopy.

Colorectal cancer prevention by a CLEAR principles-based colonoscopy protocol: an observational study

BACKGROUND AND AIMS

Colorectal cancer (CRC) prevention by colonoscopy has been lower than expected. We studied CRC prevention outcomes of a colonoscopy protocol based on Clean the colon, Look Everywhere, and complete Abnormality Removal (CLEAR) principles.

METHODS

This observational follow-up study studied patients provided screening colonoscopy at a free-standing private ambulatory surgery center in South Carolina by 80 endoscopists from October 2001 to December 2014, followed through December 2015. The colonoscopy protocol, optimized for polyp clearance, featured in-person bowel preparation instructions reinforced by phone, polyp search and removal throughout insertion and gradual withdrawal with circumferential tip movements, and a team approach using all personnel present to maximize polyp detection, patient safety, and clear-margin polypectomy including requesting repeat inspection or additional tissue removal. Outcome measures were postscreening lifetime CRC risk relative to Surveillance Epidemiology and End Results (SEER)-18 and interval cancer rate (postcolonoscopy CRCs among cancer-free patients at screening).

RESULTS

Of 25,862 patients (mean age, 58.1 years; 52% black; 205,522 person-years of observation), 159 had CRC at screening and 67 patients developed interval CRC. The interval CRC rate was 3.34 per 10,000 person-years of observation, 5.79 and 2.24 among patients with and without adenomas, respectively. The rate was similar among older patients (mean age 68.5 years at screening) and with prolonged follow-up. Postscreening lifetime CRC risk was 1.6% (bootstrap 95% confidence interval, 1.3%-1.8%) versus 4.7% in SEER-18, 67% lower. Subgroups with mean screening ages of 50 and 68.5 years showed risk reductions of 80% and 72%, respectively. The adverse event rate was less than usually reported rates: perforation 2.6 per 10,000, bleeding with hospitalization 2.4 per 10,000, and no deaths.

CONCLUSIONS

A colonoscopy protocol optimized for polyp clearance prevented 67% of CRC compared with a SEER-18 population given ongoing population screening.

Long-term Risk of Colorectal Cancer After Removal of Conventional Adenomas and Serrated Polyps

BACKGROUND & AIMS

Endoscopic screening reduces incidence and mortality of colorectal cancer (CRC) because precursor lesions, such as conventional adenomas or serrated polyps, are removed. Individuals with polypectomies are advised to undergo colonoscopy surveillance to prevent CRC. However, guidelines for surveillance intervals after diagnosis of a precursor lesion, particularly for individuals with serrated polyps, vary widely, and lack sufficient supporting evidence. Consequently, some high-risk patients do not receive enough surveillance and lower-risk subjects receive excessive surveillance.

METHODS

We examined the association between findings from first endoscopy and CRC risk among 122,899 participants who underwent flexible sigmoidoscopy or colonoscopy in the Nurses' Health Study 1 (1990-2012), Nurses' Health Study 2 (1989-2013), or the Health Professionals Follow-up Study (1990-2012). Endoscopic findings were categorized as no polyp, conventional adenoma, or serrated polyp (hyperplastic polyp, traditional serrated adenoma, or sessile serrated adenoma, with or without cytological dysplasia). Conventional adenomas were classified as advanced (≥10 mm, high-grade dysplasia, or tubulovillous or villous histology) or nonadvanced, and serrated polyps were assigned to categories of large (≥10 mm) or small (<10 mm). We used a Cox proportional hazards regression model to calculate the hazard ratios (HRs) of CRC incidence, after adjusting for various potential risk factors.

RESULTS

After a median follow-up period of 10 years, we documented 491 incident cases of CRC: 51 occurred in 6161 participants with conventional adenomas, 24 in 5918 participants with serrated polyps, and 427 in 112,107 participants with no polyp. Compared with participants with no polyp detected during initial endoscopy, the multivariable HR for incident CRC in individuals with an advanced adenoma was 4.07 (95% confidence interval [CI] 2.89-5.72) and the HR for CRC in individuals with a large serrated polyp was 3.35 (95% CI 1.37-8.15). In contrast, there was no significant increase in risk of CRC in patients with nonadvanced adenomas (HR 1.21; 95% CI 0.68-2.16, P = .52) or small serrated polyps (HR 1.25; 95% CI 0.76-2.08; P = .38).

CONCLUSIONS

These findings provide support for guidelines that recommend repeat lower endoscopy within 3 years of a diagnosis of advanced adenoma and large serrated polyps. In contrast, patients with nonadvanced adenoma or small serrated polyps may not require more intensive surveillance than patients without polyps.

Characteristics of Advanced Colorectal Cancer Detected by Fecal Immunochemical Test Screening in Participants with a Negative Result the Previous Year

BACKGROUND

There is sufficient evidence to show the mortality reduction effect of colorectal cancer (CRC) screening programs using the fecal occult blood test (FOBT). However, we see cases that are found to be advanced CRC despite yearly FOBT screening.

METHODS

The aim of this study was to investigate the characteristics of advanced CRC detected by a fecal immunochemical test (FIT) screening program in participants with a negative screening result the previous year, which we call "Negative advanced CRC". A total of 109,639 participants (10.0% required colonoscopy, of whom 76.9% received one) underwent a CRC screening program using a FIT from fiscal 2009 to 2017. Negative advanced CRC was compared with advanced CRC (First advanced CRC) found at the first visit in a person who had not had a FIT screening history for more than 3 years. In addition, we compared the characteristics of Negative advanced CRC with those of interval cancer: cancer cases detected after a negative screening result and before the date of the next recommended screening.

RESULTS

A total of 339 cases of CRC (175 male: 164 female, 173 early stage: 166 advanced stage) were detected in the nine-year CRC screening period. The rate of right-sided CRCs was significantly higher in female (P < 0.01), advanced stage (P < 0.01), negative result previous year (P < 0.01), and symptom-negative (P < 0.01) participants than in each counterpart, respectively. The ratio of female (22/35; 62.9%) patients in Negative advanced CRCs tended to be high compared with that (40/83; 48.2%) in First advanced CRCs (P = 0.145). Overall, 22 (62.9%) of 35 Negative advanced CRCs and 28 (33.7%) of 83 First advanced CRCs were located in the right-sided colon, and the rate was significantly higher in Negative advanced CRCs (P < 0.01). In addition, the frequency of female patients was significantly higher in right-sided Negative advanced CRCs than in right-sided First advanced CRCs (P = 0.03).

CONCLUSION

The characteristics of Negative advanced CRC cases (female and right-sided colon) were similar to those of interval cancer reported so far. In the future, it will be necessary to introduce a screening program that is highly sensitive to right-sided CRC.

The Relationship between Post-colonoscopy Colorectal Cancer and Quality Indicators of Colonoscopy: The Latest Single-center Cohort Study with a Review of the Literature

Objective This study aims to elucidate the association between the clinical characteristics of post-colonoscopy colorectal cancer (PCCRC) and quality indicators (QIs) of colonoscopy. Methods Patients with PCCRC who underwent total colonoscopy (TCS) and were histologically diagnosed with adenocarcinoma within six months to five years of the last examination were included in this study. PCCRC and normally detected cancer (NDC) identified within the same period were compared in terms of their clinicopathological characteristics. Furthermore, the QIs at PCCRC detection were compared to those at the last examination. Results Patients with PCCRC had a significantly higher rate of colon surgery history than those with NDC (PCCRC: 25/76, 32.9%; NDC: 31/1,437, 2.2%; p<0.001), but the invasion depth in these patients was significantly shallower (PCCRC: ≤Tis/≥T1, 37/39; NDC: ≤Tis/≥T1, 416/1,021; p<0.001). Among patients with PCCRC, the T1b group had significantly more non-polypoid growth (NPG)-type cases than PG-type CRC cases (p=0.018). The adenoma detection rate (ADR) of colonoscopists performing TCS was 30.2-52.8%. Furthermore, the ADR of colonoscopists at the time of PCCRC detection (36.7%±5.9%) was significantly higher than that of colonoscopists who performed the last examination (34.9%±4.4%; p=0.034). The withdrawal time for negative colonoscopy (WT-NC) at detection was significantly longer than that at the last examination (at detection: 494.3±253.8 s; at last examination: 579.5±243.6 s; p=0.010). Conclusion Given that these PCCRC cases were post-colon surgery cases, had a long WT-NC, and were detected by colonoscopists with a high ADR, most cases showed lesions that were missed during the previous colonoscopy. Caution should be practiced in order to avoid missing flat, NPG-type tumors.

Epidemiology, characteristics, and survival of post-colonoscopy colorectal cancer in Asia: A population-based study

BACKGROUND AND AIM

Population-based studies on post-colonoscopy colorectal cancer (CRC) from Asia are sparse. We aimed to determine the characteristics and predictive factors and survival of post-colonoscopy CRC in Hong Kong.

METHODS

This is a territory-wide retrospective cohort study. Patients aged ≥ 40 years with colonoscopies performed between 2005 and 2013 without history of CRCs, inflammatory bowel disease, and prior colectomy were included. Post-colonoscopy colorectal cancer for an interval of 3 years (PCCRC-3y) was defined as CRC diagnosed between 6 and 36 months after index colonoscopy, whereas CRC diagnosed within 6 months of index colonoscopy was regarded as "detected CRC." We used multivariable logistic regression to derive adjusted odds ratio (aOR) of PCCRC-3y and Cox model for adjusted hazard ratio (aHR) of cancer-specific mortality after CRC diagnosis.

RESULTS

Of the 197 902 eligible patients, 10 005 (92.1%) were detected CRC and 854 (7.9%) PCCRC-3y. The median age at PCCRC-3y diagnosis was 75.9 years (interquartile range: 65.5-83.8)-a delay of 1.2 years (interquartile range: 0.8-1.9) from index colonoscopy-and 60.1% were male. Predictive factors for PCCRC-3y included older age (aOR: 1.07), male sex (aOR: 1.45), history of colonic polyps (aOR: 1.31), polypectomy/biopsy at index colonoscopy (aOR: 3.97), surgical endoscopists (aOR: 1.53), and a higher center annual endoscopy volume. Independent predictive factors for cancer-specific mortality after CRC diagnosis included PCCRC-3y (aHR: 1.32), proximal cancer location (aHR: 1.80), and certain patient factors.

CONCLUSION

The PCCRC-3y rate was 7.9% in Hong Kong, with a high proportion (> 80%) of distal cancers and a higher cancer-specific mortality compared with detected CRC.

Screen-detected and interval colorectal cancers in England: Associations with lifestyle and other factors in women in a large UK prospective cohort

Faecal occult blood (FOB) - based screening programmes for colorectal cancer detect about half of all cancers. Little is known about individual health behavioural characteristics which may be associated with screen-detected and interval cancers. Electronic linkage between the UK National Health Service Bowel Cancer Screening Programme (BCSP) in England, cancer registration and other national health records, and a large on-going UK cohort, the Million Women Study, provided data on 628,976 women screened using a guaiac-FOB test (gFOBt) between 2006 and 2012. Relative risks (RRs) and 95% confidence intervals (CIs) were estimated by logistic and Cox regression for associations between individual lifestyle factors and risk of colorectal tumours. Among screened women, 766 were diagnosed with screen-detected colorectal cancer registered within 2 years after a positive gFOBt result, and 749 with interval colorectal cancers registered within 2 years after a negative gFOBt result. Current smoking was significantly associated with risk of interval cancer (RR 1.64, 95%CI 1.35-1.99) but not with risk of screen-detected cancer (RR 1.03, 0.84-1.28), and was the only factor of eight examined to show a significant difference in risk between interval and screen-detected cancers (p for difference, 0.003). Compared to screen-detected cancers, interval cancers tended to be sited in the proximal colon or rectum, to be of non-adenocarcinoma morphology, and to be of higher stage.

Cost-effectiveness of adding Endocuff® to standard colonoscopies for interval colorectal cancer screening

Background and aims: Higher screening colonoscopy adenoma detection rates (ADRs) correlate with reduced risk of interval colorectal cancer (CRC). The Endocuff® device has been shown to improve ADRs compared to standard colonoscopy (SC). This cost-effectiveness analysis compared interval CRC screening using Endocuff®-assisted colonoscopy (EC) vs SC. Methods: A decision-analytic Markov model followed patients through screening, CRC diagnosis, progression, remission, and death. ADRs, CRC progression, and utilities were from literature. CRC incidence, stage distribution, and mortality were from the Surveillance, Epidemiology, and End Results (SEER) and SEER-Medicare linked databases. Screening and annual patient costs were from public databases and literature. Endocuff® device average sales price was applied. Lifetime device and medical costs were evaluated separately for device purchaser, health plan, and accountable care organization (ACO) perspectives. Results: Consistent use of EC instead of SC was expected to reduce lifetime risks of interval CRC and related death by 0.98% and 0.19%, respectively, preventing one case per 102 patients and one death per 526 patients. Survival and quality-of-life (QoL) improved by 0.025 life-years and 0.011 quality-adjusted life-years (QALYs) per patient on average. EC instead of SC led to incremental cost-effectiveness ratios to the device purchaser of $4,421 per life-year gained and $9,843 per QALY gained, and $199 or $87 average cost-savings per patient to the health plan or ACO, respectively. Conclusion: Endocuff® for screening colonoscopies was expected to reduce interval CRC incidence and death, improve QoL, and be cost-effective to the device purchaser and cost-saving to a health plan or ACO.

No Interval Cancers in Endoscopic Practice

Colonoscopy is long time the most preferred method for CRC screening along with diagnosis and treatment for a range of colon diseases. Based on its difficulty in visualizing precursor CRC lesions, mostly those located on the right colon, this method can be subject of improvement. The colonoscopy quality can be influenced by many factors such as colon preparation, retraction time, the colonoscopists medical training and knowledges as well as the performance of endoscopy equipment. The bad quality of colonoscopy will result in the emergence of interval cancers defined, based on the author, as cancers that appear at 3-5 years up to 10 years from the colonoscopy procedure. Interval cancers have predominantly incriminated both the colonoscopy quality and the clinician competences and less the tumor biology. Subsequently there were set quality indicators of colonoscopy in order to raise the quality of the exploration. Among the important indicators, proving their utility in studies, the ADR (adenoma detection rate) is most commonly used along with PDR (polyp detection rate) and APC (adenoma per colonoscopy). Following the purpose of obtaining a higher colonoscopy quality the medical units should keep in check all indicators. Furthermore, there should be an active involvement in an additional training of non-conforming medical personnel or even restrain of practice, given the medical legal actions that have interval cancers as a main cause.

Interval cancers after negative immunochemical test compared to screen and non-responders' detected cancers in Slovenian colorectal cancer screening programme

Background

We assessed the incidence and characteristics of interval cancers after faecal immunochemical occult blood test and calculated the test sensitivity in Slovenian colorectal cancer screening programme.

Patients and methods

The analysis included the population aged between 50 to 69 years, which was invited for screening between April 2011 and December 2012. The persons were followed-up until the next foreseen invitation, in average for 2 years. The data on interval cancers and cancers in non-responders were obtained from cancer registry. Gender, age, years of schooling, the cancer site and stage were compared among three observed groups. We used the proportional incidence method to calculate the screening test sensitivity.

Results

Among 502,488 persons invited for screening, 493 cancers were detected after positive screening test, 79 interval cancers after negative faecal immunochemical test and 395 in non-responders. The proportion of interval cancers was 13.8%. Among the three observed groups cancers were more frequent in men (p = 0.009) and in persons aged 60+ years (p < 0.001). Comparing screen detected and cancers in non-responders with interval cancers more interval cancers were detected in persons with 10 years of schooling or more (p = 0.029 and p = 0.001), in stage III (p = 0.027) and IV (p < 0.001), and in right hemicolon (p < 0.001). Interval cancers were more frequently in stage I than non-responders cancers (p = 0.004). Test sensitivity of faecal immunochemical test was 88.45%.

Conclusions

Interval cancers in Slovenian screening programme were detected in expected proportions as in similar programmes. Test sensitivity was among the highest when compared to similar programmes and was accomplished using test kit for two stool samples.

PAM50 and Risk of Recurrence Scores for Interval Breast Cancers

Breast cancers detected after a negative breast screening examination and prior to the next screening are referred to as interval cancers. These cancers generally have poor clinical characteristics compared with screen-detected cancers, but associations between interval cancer and genomic cancer characteristics are not well understood. Mammographically screened women diagnosed with primary invasive breast cancer from 1993 to 2013 (n = 370) were identified by linking the Carolina Breast Cancer Study and the Carolina Mammography Registry. Among women with a registry-identified screening mammogram 0 to 24 months before diagnosis, cancers were classified as screen-detected (N = 165) or interval-detected (N = 205). Using logistic regression, we examined the association of mode of detection with cancer characteristics (clinical, IHC, and genomic), overall, and in analyses stratified on mammographic density and race. Interval cancer was associated with large tumors [>2 cm; OR, 2.3; 95% confidence interval (CI), 1.5-3.7], positive nodal status (OR, 1.8; 95% CI, 1.1-2.8), and triple-negative subtype (OR, 2.5; 95% CI, 1.1-5.5). Interval cancers were more likely to have non-Luminal A subtype (OR, 2.9; 95% CI, 1.5-5.7), whereas screen-detected cancers tended to be more indolent (96% had low risk of recurrence genomic scores; 71% were PAM50 Luminal A). When stratifying by mammographic density and race, associations between interval detection and poor prognostic features were similar by race and density status. Strong associations between interval cancers and poor-prognosis genomic features (non-Luminal A subtype and high risk of recurrence score) suggest that aggressive tumor biology is an important contributor to interval cancer rates. Cancer Prev Res; 11(6); 327-36. ©2018 AACR.

The contribution of a negative colorectal screening test result to symptom appraisal and help-seeking behaviour among patients subsequently diagnosed with an interval colorectal cancer

Background

Colorectal cancer (CRC) screening programmes using a guaiac faecal occult blood test (gFOBt) reduce CRC mortality. Interval cancers are diagnosed between screening rounds: reassurance from a negative gFOBt has the potential to influence the pathway to diagnosis of an interval colorectal cancer.

Methods

Twenty‐six semi‐structured face‐to‐face interviews were carried out in Scotland and England, with individuals diagnosed with an interval colorectal cancer following a negative gFOBt result.

Results

Participants reported they were reassured by a negative gFOBt, interpreting their result as an “all clear”. Therefore, most did not suspect cancer as a possible cause of symptoms and many did not recall their screening result during symptom appraisal. Among those who did consider cancer, and did think about their screening test result, reassurance from a negative gFOBt led some to “downplay” the seriousness of their symptoms with some interviewees explicitly stating that their negative test result contributed to a delayed decision to seek help.

Conclusion

Screening participants need to be informed of the limitations of screening and the ongoing risk of developing colorectal cancer even when in receipt of a negative result: the importance of minimizing delay in seeking medical advice for colorectal symptoms should be emphasized.

Cumulative risk of breast cancer screening outcomes according to the presence of previous benign breast disease and family history of breast cancer: supporting personalised screening

BACKGROUND

Our aim was to assess the cumulative risk of false-positive screening results, screen-detected cancer, and interval breast cancer in mammography screening among women with and without a previous benign breast disease and a family history of breast cancer.

METHODS

The cohort included 42 928 women first screened at the age of 50-51 years at three areas of the Spanish Screening Programme (Girona, and two areas in Barcelona) between 1996 and 2011, and followed up until December 2012. We used discrete-time survival models to estimate the cumulative risk of each screening outcome over 10 biennial screening exams.

RESULTS

The cumulative risk of false-positive results, screen-detected breast cancer, and interval cancer was 36.6, 5.3, and 1.4 for women with a previous benign breast disease, 24.1, 6.8, and 1.6% for women with a family history of breast cancer, 37.9, 9.0, and 3.2%; for women with both a previous benign breast disease and a family history, and 23.1, 3.2, and 0.9% for women without either of these antecedents, respectively.

CONCLUSIONS

Women with a benign breast disease or a family history of breast cancer had an increased cumulative risk of favourable and unfavourable screening outcomes than women without these characteristics. A family history of breast cancer did not increase the cumulative risk of false-positive results. Identifying different risk profiles among screening participants provides useful information to stratify women according to their individualised risk when personalised screening strategies are discussed.

Interval cancers after skin cancer screening: incidence, tumour characteristics and risk factors for cutaneous melanoma

BACKGROUND

The rate of interval cancers is an established indicator for the performance of a cancer-screening programme.

METHODS

We examined the incidence, tumour characteristics and risk factors of melanoma interval cancers that occurred in participants of the SCREEN project, which was carried out 2003/2004 in Schleswig-Holstein, Germany. Data from 350 306 SCREEN participants, who had been screened negative for melanoma, were linked to data of the state cancer registry. Melanoma interval cancers were defined as melanomas diagnosed within 4-24 months after SCREEN examination. Results were compared with melanomas of the pre-SCREEN era (1999-2002), extracted from the cancer registry.

RESULTS

The overall relative incidence of melanoma interval cancers in terms of observed/expected ratio was 0.93 (95% CI: 0.82-1.05; in situ: 1.61 (1.32-1.95), invasive: 0.71 (0.60-0.84)). Compared with melanomas of the pre-SCREEN era, the interval melanomas were thinner and had a slightly greater proportion of lentigo maligna melanomas whereas nodular melanomas were less frequent.

INTERPRETATION

The results indicate a moderate performance of the SCREEN intervention with an excess of in situ melanomas. In part, the findings might be due to specifics of the SCREEN project, in particular a short-term follow-up of patients at high risk for melanoma.

Longitudinal fluctuation in mammographic percent density differentiates between interval and screen-detected breast cancer

Interval breast cancer (IC) has a more aggressive phenotype and higher mortality than screen-detected cancer (SDC). In this case-case study, we investigated whether the size of longitudinal fluctuations in mammographic percent density (PD fluctuation) was associated with the ratio of IC versus SDC among screened women with breast cancer. The primary study population consisted of 1,414 postmenopausal breast cancer cases, and the validation population of 1,241 cases. We calculated PD fluctuation as the quadratic mean of deviations between actual PD and the long-term trend estimated by a mixed effects model. In a logistic regression model we examined the association between PD fluctuation and IC versus SDC including adjustments for PD at last screening, age at diagnosis, BMI and hormone replacement therapy. All statistical tests were two-sided. There were 385 IC and 1,029 SDC in the primary study population, with PD fluctuations of 0.44 and 0.41 respectively (p = 0.0309). After adjustments, PD fluctuation was associated with an increased ratio of IC versus SDC, with an estimated per-standard deviation odds ratio of 1.17 (95% CI = 1.03-1.33), compared to 1.19 (95% CI = 1.04-1.38) in the validation population. In screened women with breast cancer, high fluctuation in mammographic percent density was associated with an increased ratio of IC versus SDC. Whether this is entirely related to a reduced mammographic detectability or to a biological phenotype promoting faster tumor growth remains to be elucidated.

Digital vs screen-film mammography in population-based breast cancer screening: performance indicators and tumour characteristics of screen-detected and interval cancers

BACKGROUND

Full-field digital mammography (FFDM) has replaced screen-film mammography (SFM) in most breast cancer screening programs due to technological advantages such as possibilities to adjust contrast, better image quality and transfer capabilities. This study describes the performance indicators during the transition from SFM to FFDM and the characteristics of screen-detected and interval cancers.

METHODS

Data of the Dutch breast cancer screening program, region North from 2004 to 2010 were linked to The Netherlands Cancer Registry (N=902 868). Performance indicators and tumour characteristics of screen-detected and interval cancers were compared between FFDM and SFM.

RESULTS

After initial screens, recall rates were 2.1% (SFM) and 3.0% (FFDM; P<0.001). The positive predictive values (PPV) were 25.6% (SFM) and 19.9% (FFDM; P=0.002). Detection rates were similar, as were all performance indicators after subsequent screens. Similar percentages of low-grade ductal carcinoma in situ (DCIS) were found for SFM and FFDM. Invasive cancers diagnosed after subsequent screens with FFDM were more often of high-grade (P=0.024) and ductal type (P=0.030). The incidence rates of interval cancers were similar for SFM and FFDM after initial (2.69/1000 vs 2.51/1000; P=0.787) and subsequent screens (2.30 vs 2.41; P=0.652), with similar tumour characteristics.

CONCLUSIONS

FFDM resulted in similar rates of screen-detected and interval cancers, indicating that FFDM performs as well as SFM in a breast cancer screening program. No signs of an increase in low-grade DCIS (which might connote possible overdiagnosis) were seen. Nonetheless, after initial screening, which accounts for 12% of all screens, FFDM resulted in higher recall rate and lower PPV that requires attention.

Interval cancers in a national colorectal cancer screening programme

BACKGROUND

Little is known about interval cancers (ICs) in colorectal cancer (CRC) screening.

OBJECTIVE

The purpose of this study was to identify IC characteristics and compare these with screen-detected cancers (SCs) and cancers in non-participants (NPCs) over the same time period.

DESIGN

This was an observational study done in the first round of the Scottish Bowel Screening Programme. All individuals (772,790), aged 50-74 years, invited to participate between 1 January 2007 and 31 May 2009 were studied by linking their screening records with confirmed CRC records in the Scottish Cancer Registry (SCR). Characteristics of SC, IC and NPC were determined.

RESULTS

There were 555 SCs, 502 ICs and 922 NPCs. SCs were at an earlier stage than ICs and NPCs (33.9% Dukes' A as against 18.7% in IC and 11.3% in NPC), screening preferentially detected cancers in males (64.7% as against 52.8% in IC and 59.7% in NPC): this was independent of a different cancer site distribution in males and females. SC in the colon were less advanced than IC, but not in the rectum.

CONCLUSION

ICs account for 47.5% of the CRCs in the screened population, indicating approximately 50% screening test sensitivity: guaiac faecal occult blood testing (gFOBT) sensitivity is less for women than for men and gFOBT screening may not be effective for rectal cancer.

Towards personalized screening: Cumulative risk of breast cancer screening outcomes in women with and without a first-degree relative with a history of breast cancer

Several reviews have estimated the balance of benefits and harms of mammographic screening in the general population. The balance may, however, differ between individuals with and without family history. Therefore, our aim is to assess the cumulative risk of screening outcomes; screen-detected breast cancer, interval cancer, and false-positive results, in women screenees aged 50-75 and 40-75, with and without a first-degree relative with a history of breast cancer at the start of screening. Data on screening attendance, recall and breast cancer detection were collected for each woman living in Nijmegen (The Netherlands) since 1975. We used a discrete time survival model to calculate the cumulative probability of each major screening outcome over 19 screening rounds. Women with a family history of breast cancer had a higher risk of all screening outcomes. For women screened from age 50-75, the cumulative risk of screen-detected breast cancer, interval cancer and false-positive results were 9.0, 4.4 and 11.1% for women with a family history and 6.3, 2.7 and 7.3% for women without a family history, respectively. The results for women 40-75 followed the same pattern for women screened 50-75 for cancer outcomes, but were almost doubled for false-positive results. To conclude, women with a first-degree relative with a history of breast cancer are more likely to experience benefits and harms of screening than women without a family history. To complete the balance and provide risk-based screening recommendations, the breast cancer mortality reduction and overdiagnosis should be estimated for family history subgroups.