Tumor location and detectability in mammographic screening

Area of Science:

• Radiology
• Oncology
• Medical Imaging

Background:

• Radiologists have concerns about the adequacy of film mammograms that do not visualize the retromammary space or ribs.
• Assessing screening mammography effectiveness is crucial for early breast cancer detection.

Purpose of the Study:

• To evaluate the adequacy of film mammography in detecting prevalent breast cancers.
• To analyze cancer characteristics and detection rates in a large screening population.

Main Methods:

• Analysis of 79 prevalent cancers from 10,000 women undergoing screening mammography.
• Mammograms obtained using dedicated equipment with vigorous compression, visualizing the anterior axillary fold.
• Focus on cancers detectable on mammograms, their location, size, and histologic type.

Main Results:

• 76 out of 79 prevalent cancers were detectable on mammograms.
• All cancers were visualized on the mediolateral view; 3 were missed on the craniocaudal view.
• Detected cancers were smaller and had a higher proportion of noninvasive types compared to symptomatic cases.

Conclusions:

• Film mammography with vigorous compression adequately examines the breast for cancer detection, even without imaging ribs.
• The mediolateral view is essential for visualizing cancers near the posterior edge.
• Screening mammography detects smaller, less advanced cancers compared to clinical diagnosis.