Cancer screening and detection in family practice: a MIRNET study

The identification of effective strategies for the prevention, diagnosis, and treatment of cancer is a high priority for the nation, yet relatively little is known about how cancer is diagnosed in primary care. This study was undertaken to describe practitioner beliefs about cancer screening and to determine whether beliefs and intentions about cancer screening are associated with actual cancer detection rates among asymptomatic patients cared for by family physicians.

A self-administered questionnaire on cancer screening beliefs and practices was completed by members of the Michigan Research Network (MIRNET) in January 1990 and again in December of 1990. Thirty-one practitioners prospectively identified all patients with a new diagnosis of cancer during 1990.

One hundred sixteen cancer cases were identified. Only 31% of the 77 cancers considered to be potentially detectable by routine screening were actually identified by screening. Physicians reporting more aggressive screening practices identified greater percentages of asymptomatic cancers and a greater number of breast and colon cancers.

Low percentages of cancers were detected in asymptomatic patients in this population. Practitioner attitudes about the need for cancer screening appear to be an important component of cancer detection.