Journal of Medical Screening

Some degree of general worry about cancer may facilitate screening participation, but specific worries about the potential consequences (e.g. treatment, death) may act as deterrents. No studies have examined these associations in the same sample. We assessed associations between general versus specific cancer worries and cancer screening participation.

In 2016, a population-based cross-sectional survey of adults living in England was carried out. This paper reports analyses of a subsample (n = 1694). Measures included (i) frequency of general cancer worry, (ii) specific worries about the emotional and physical consequences of a cancer diagnosis, and (iii) specific worries about the social consequences of a cancer diagnosis. Logistic regression analyses examined their association with self-reported screening uptake among participants eligible for cervical (n = 671), breast (n = 323), and colorectal (n = 368) cancer screening.

Frequency of general cancer worry was not associated with screening participation. Specific worry about the emotional and physical consequences increased the odds of participants reporting regular uptake of colorectal screening (OR 1.41, 95% CI 1.04–1.90). Specific worry about the social consequences of diagnosis was negatively associated with regular attendance for cervical and breast screening in unadjusted analyses only. In adjusted models, the associations were no longer statistically significant for cervical (OR 0.82, 95% CI 0.65–1.03) or breast (OR 0.69, 95% CI 0.45–1.04) screening.

Specific worries about cancer may be differentially associated with participation across screening programmes. Further research is needed, as interventions to optimise informed participation may be improved if the specific worries associated with low participation in each programme are understood.

To investigate the outcomes of biennial guaiac faecal occult blood test (gFOBT) screening after once-only flexible sigmoidoscopy (FS) screening.

Between 1994 and 1999, as part of the UK FS Screening Trial (UKFSST), adults aged 55–64 were randomly allocated to an intervention group (offered FS screening) or a control group (not contacted). From 2006, a subset of UKFSST participants (20,895/44,041 intervention group; 41,497/87,149 control group) were invited to biennial gFOBT screening by the English Bowel Cancer Screening Programme. We analysed gFOBT uptake, test positivity, yield of colorectal cancer (CRC), and positive predictive value (PPV) for CRC, advanced adenomas (AAs), and advanced colorectal neoplasia (ACN: AA/CRC).

Uptake of gFOBT at first invitation was 1.9% lower (65.7% vs. 67.6%, p < 0.01) among intervention versus control group participants. Positivity was 0.4% lower (2.0% vs. 2.4%, p < 0.01) and CRC yield was 0.08% lower (0.19% vs. 0.27%, p = 0.14). PPVs were also lower in the intervention versus control group, at 10.3% vs. 12.3% (p = 0.44) for CRC, 22.7% vs. 31.4% (p < 0.01) for AA, and 33.0% vs. 43.7% (p < 0.01) for ACN. Among those who refused FS (n = 5532), gFOBT uptake at first invitation was 47.7%, CRC yield was 0.25%, and PPV for ACN was 46.2%. Among FS attenders (n = 15,363), uptake was 72.2%, CRC yield was 0.18%, and PPV for ACN was 27.9%.

Uptake, positivity and PPV of gFOBT screening were reduced following prior offer of FS screening. However, a quarter of FS screened participants receiving a diagnostic examination after positive gFOBT were diagnosed with ACN.

In evaluating the efficacy of cancer screening programmes, sojourn time (duration of the preclinical detectable phase) and sensitivity of the screening test are the two key parameters. Studies suggest that in breast cancer screening, both parameters may vary depending on age at the time of screening, but few studies have examined other cancers. We expanded an existing probability model for periodic screening by performing simultaneous estimation of age group-dependent and sensitivity at preclinical onset time, and tested the expanded model using data from the Korean National Colorectal Cancer Screening Programme.

Simulation studies were conducted to assess the performance of the proposed probability model. The method was then applied to the analysis of 376,542 participants aged 50 or over who underwent fecal occult blood testing (FOBT) as part of the National Colorectal Cancer Screening Programme between 2004 and 2007. Age group-dependent mean sojourn time and screening sensitivity of FOBT for colorectal cancer were derived using maximum likelihood estimation.

The method performed well in terms of bias, standard deviation, and coverage probability. National Colorectal Cancer Screening Programme data results indicated that the sensitivity of FOBT to detect colorectal cancer increases with age, while mean sojourn time decreases with age (approximately 4.3 years for participants aged 50–54, 3.9 years at age 55–59, 3.4 years at age 60–64, and 3.6 years at age 65–69, with corresponding sensitivity estimates around 41%, 47%, 45%, and 51%, respectively).

Simulation studies showed that the proposed stochastic model considering both mean sojourn time and sensitivity yields highly accurate results.

To investigate the impact of population mammography screening on breast cancer incidence trends in New Zealand.

Trends in age-specific rates of invasive breast cancer incidence (1994–2014) were assessed in relation to screening in women aged 50–64 from 1999 and 45–69 following the programme age extension in mid-2004.

Breast cancer incidence increased significantly by 18% in women aged 50–64 compared with 1994–98 (p<0.0001), coinciding with the 1999 introduction of mammography screening, and remained elevated for four years, before declining to pre-screening levels. Increases over 1994–99 incidence occurred in the 45–49 (21%) and 65–69 (19%) age groups following the 2004 age extension (p<0.0001). Following establishment of screening (2006–10), elevated incidence in the screening target age groups was compensated for by lower incidence in the post-screening ⩾70 age groups than in 1994–98. Incidence in women aged ⩾45 was not significantly higher (+5%) after 2006 than in 1994–98. The cumulated risk of breast cancer in women aged 45–84 for 1994–98 was 10.7% compared with 10.8% in 2006–10.

Increases in breast cancer incidence following introduction of mammography screening in women aged 50–64 did not persist. Incidence inflation also occurred after introduction of screening for age groups 45–49 and 65–69. The cumulated incidence for women aged 45–84 over 2006–10 after screening was well established, compared with 1994–98 prior to screening, shows no increase in diagnosis. Over-diagnosis is not inevitable in population mammography screening programmes.

To investigate trends in breast cancer mortality in New Zealand women, to corroborate or negate a causal association with service screening mammography.

Cumulated mortality rates from breast cancer deaths individually linked to incident cases diagnosed before and after screening commencement were compared, in women aged 50–64 (from 2001) and aged 45–49 and 65–69 (from 2006). Trends and differences in aggregate invasive breast cancer mortality (1975–2013) were assessed in relation to introduction of mammography screening targeting women aged 50–64 and 45–69. Joinpoint analysis was also undertaken.

The reduction in incidence-based cumulated breast cancer mortality before and after the introduction of screening was −15% (p = 0.006) for women aged 45–69, and 17% (p = 0.005) for those aged 50–64. Aggregate mortality declined by −34% (2005–13 compared with 1992–98) in the age group 50–64, and by –28% among women aged 45–49 and –25% among women aged 65–74. For women aged 50–64 the 2-joinpoint model shows a 1990 turning point, from prior rising mortality to a mean −1.8% decline per annum, coinciding with improvements in primary treatment of breast cancer; and a steepening of the decline (−3.0% p.a.) from the late 1990s, coinciding with the introduction of service mammography screening.

Breast cancer mortality declines occurring since the advent of screening mammography in New Zealand are consistent with other incidence-based and aggregate studies of screening mammography in populations, individual-based cohort studies, and randomized controlled trials.

It often takes considerable time for sufficient evidence to accumulate to support implementation of new methods in routine screening. Where national screening programmes are already effective, switching to a more sensitive screening test may not be a priority. Although risk associated with overly rapid implementation exists, postponement is also associated with a (to date unquantified) missed opportunity to prevent deaths. This risk tends not to be addressed where effective screening methods are already in use. We here estimate the monetary value of a one-year delay in replacing cytology cervical screening with human papillomavirus testing.

Using a previously validated model, we calculated the number of incident and fatal cervical cancers that would be diagnosed by 2030 in England, under the assumption that human papillomavirus testing replaces cytology in 2020 rather than 2019, and the monetary value of the quality-adjusted life years lost in preventable cases.

A one-year delay in the implementation of human papillomavirus screening would miss the opportunity to prevent 581 cases of cervical cancer, and lead to a loss of 1595 quality-adjusted life years (3.5% discount rate) with a monetary value of £32 million (at £20,000 per quality-adjusted life year).

This is a measurable loss and should be considered in prioritising decision-making in screening.

The National Lung Screening Trial demonstrated the benefits of lung cancer screening, but the potential high incidence of unnecessary invasive testing for ultimately benign radiologic findings causes concern. We aimed to review current biopsy patterns and outcomes in our community-based program, and retrospectively apply malignancy prediction models in a lung cancer screening population, to identify the potential impact these calculators could have on biopsy decisions.

Retrospective review of lung cancer-screening program participants from 2013 to 2016. Demographic, biopsy, and outcome data were collected. Malignancy risk calculators were retrospectively applied and results compared in patients with positive imaging findings.

From 520 individuals enrolled in the screening program, pulmonary nodule(s) ≥6 mm were identified in 166, with biopsy in 30. Malignancy risk probabilities were significantly higher (Brock p < 0.00001; Mayo p < 0.00001) in those undergoing diagnostic sampling than those not undergoing sampling. However, there was no difference in the Brock (p = 0.912) or Mayo (p = 0.435) calculators when discriminating a final diagnosis of cancer from not cancer in those undergoing sampling.

In our screening program, 5.7% of individuals undergo invasive testing, comparable with the National Lung Screening Trial (6.1%). Both Brock and Mayo calculators perform well in indicating who may be at risk of malignancy, based on clinical and radiologic factors. However, in our invasive testing group, the Brock and Mayo calculators and Lung Cancer Screening Program clinical assessment all lacked clarity in distinguishing individuals who have a cancer from those with a benign abnormality.