The cumulative risk of false‐positive results in the Norwegian Breast Cancer Screening Program: Updated results

Abstract

BACKGROUND: Some false-positive results are inevitable in mammographic screening, but the impact of false-positive findings on the program and the participants is a disadvantage of screening. The objective of the current study was to estimate the cumulative risk of a false-positive result over 10 biennial screening examinations and the cumulative risk of undergoing an invasive procedure with a benign outcome in women screened between the ages of 50 years to 69 years. METHODS: A retrospective cohort study was performed in 231,310 women aged 50 years to 51 years at the time of first mammography screening who underwent 715,311 screening mammograms in the Norwegian Breast Cancer Screening Program from 1996 through 2010. Generalized linear mixed models were used to estimate the probability of a false-positive screening result and to compute the cumulative false-positive risk for up to 10 biennial screening examinations. RESULTS: The cumulative false-positive risk after 20 years of biennial screening for women who initiated screening aged 50 years to 51 years was 20.0% (95% confidence interval [95% CI], 19.7%-20.4%). The cumulative risk of undergoing an invasive procedure with a benign outcome for the same group of women was 4.1% (95% CI, 3.9%-4.3%). The cumulative risk of undergoing a fine-needle aspiration cytology, core needle biopsy, or open biopsy with a benign outcome was 1.4% (95% CI, 1.3%-1.5%), 2.0% (95% CI, 1.9%-2.1%), and 0.16% (95% CI, 0.13%-0.19%), respectively. CONCLUSIONS: One in every 5 women will be recalled for further assessment with a negative outcome if they attend biennial mammographic screening between ages 50 years to 69 years. The risk of an invasive procedure with a benign outcome is approximately 4%. It is important to communicate the existence and extent of this risk to the target group and to reduce to a minimum the waiting times between screening and further assessment. Cancer 2013;119:3952-8.

Statistical Methods for Estimating the Cumulative Risk of Screening Mammography Outcomes

“…Similar to prior studies comparing screening in the US and Europe, we found substantially higher risks of false-positive recall in the BCSC compared to Nijmegen, while risks of screen-detected cancer were similar (12, 20, 24). Possible explanations for these differences include the opportunistic nature of screening in the US, as compared to organized population-based screening in Europe; differences in the medico-legal context; and differences in interpretive volumes required for radiologist accreditation.…”

“…A number of prior studies have estimated the cumulative risk of a false-positive screening mammography result using data from European population-based screening programs (7-9, 12, 20). Some of these studies have used discrete-time survival estimates (7, 12, 20) while others have used simpler approximations that assume independence of risk across screening rounds (8, 9).…”

“…Some of these studies have used discrete-time survival estimates (7, 12, 20) while others have used simpler approximations that assume independence of risk across screening rounds (8, 9). In a recent comparison of the cumulative risk of false-positive results in Denmark using discrete-time survival methods with and without adjustment for dependent censoring, little difference in estimates was found, suggesting that dependent censoring plays little role in this setting (20).…”

Bidrar overdiagnostikk til høye melanomtall?

“…At the individual level, the risk of a false-positive result varies with mammographic density [109], which is associated with hormone therapy and other breast cancer risk factors [154]. At a population level, the risk of a false-positive result will depend on the distribution of such factors in the population and on technical and organizational aspects of the screening program that affects sensitivity (digital versus film mammography, double versus single reading, experience/reading volume of the radiologist, acceptance of mistakes and trends in medical ethics -i.e.…”

Les miracles au péril de la science1

“…Encore de nos jours, de nombreux tests utilisés pour poser un diagnostic de cancer comportent un risque de faux positif. Le risque est particulièrement élevé lors du dépistage de cancers précoces asymptomatiques (Crothers et al, 2014;Roman et al, 2013). Si, à la suite de ce mauvais diagnostic, le patient se rend à Lourdes ou prie un saint d'intercéder auprès de Dieu pour que celui-ci le guérisse, il sera facile de conclure au miracle.…”