RSNA2021 Redefining Radiology
Daily Bulletin

Women Prefer False Positives Over Missed Breast Cancer, Survey Finds

Monday, Nov. 29, 2021

By Toni Vomweg

According to the results of a large German study, the vast majority of women who participate in breast cancer screening prefer a reliable cancer diagnosis over avoiding false-positive findings. Toni Vomweg, MD, a radiologist in the Department of Diagnostic and Interventional Radiology at Radiologisches Institut in Koblenz, Germany, presented the research findings at RSNA 2021.

"The value of mammography is widely recognized and broadly used for screening because of its proven impact on breast cancer mortality," Dr. Vomweg said. "However, other methods, such as ultrasound and MRI, can improve early diagnosis, especially in women with dense breasts."

Compared to mammography, Dr. Vomweg said MRI detects two to three times more breast cancers — but also delivers two to three times as many false-positive findings.

"Some argue that screening methods, such as breast MRI, that further increase the number of false-positive diagnoses compared to mammographic screening are unacceptable to women," he said.

However, Dr. Vomweg said women's preferences for screening methods are unknown. His research team investigated the question with a group of women undergoing routine screening at three sites of the German Mammography Screening Program. The program invites all women age 50 to 69 to a digital breast cancer screening with a letter that includes an in-depth explanation of mammographic screening, including its effectiveness, negative effects, and the concept of overdiagnosis.

The researchers developed a questionnaire in cooperation with psychologists and women's representatives that explained in clear language that screening methods can cause 'false alarms' (false-positive findings) and can also be false-negative. Women were asked two questions with inversed phrasing whether they preferred a screening method that avoids false-negative diagnoses, even if it increased the rate of false-positives, or whether they wanted a method that avoids false alarms — but may not always find cancer.

Consecutive women presenting for routine screening were offered the questionnaire. Of the 1,126 anonymous questionnaires returned by participants, 906 were complete. Of those, the majority (851 or 93.9%) of participants said they preferred a more sensitive method of breast cancer detection even if it meant accepting more false-positive findings. Only 55 (6.1%) said they preferred avoiding more frequent false alarms. The findings were independent of the women's age or level of education.

"Currently, mammographic screening is criticized mainly because over-diagnosis, the effects of overtreatment and the harm caused by false-positive diagnosis," he said. "However, Germany's age-adjusted incidence and mortality rates from 1999-2017 demonstrates that the over-diagnosis of breast cancer is rare."

Dr. Vomweg said high breast cancer mortality, even in countries with established breast cancer screening programs, is the result of failing to diagnose breast cancer early enough.

Access the presentation, "Attitude of Women Towards Screening for Breast Cancer: Readiness to Accept False Positive vs. False Negative Diagnoses," (SPR-BR-23) on demand