Abstract
One hundred eighty-five cases of primary breast cancer cases treated surgically at our hospital between January 2001 and December 2005 were divided into three groups based on the disease state at the time of discovery. These three groups included 40 asymptomatic cases detected by breast cancer screening (screening group), 23 cases of benign conditions detected at follow-up (follow-up group), and 122 cases detected as a result of symptoms (symptomatic group). These groups were then evaluated retrospectively to assess the usefulness of ultrasonography (US) for breast cancer detection.
The average tumor diameter was 14.0mm in the screening group, 10.8mm in the follow-up group, and 24.6mm in the symptomatic group. In these groups, the sensitivity of US was 90.0%, 95.7%, and 100%, respectively, when each category over 3 was considered as positive. The sensitivity of mammography (MMG) was 85.0%, 73.9%, and 96.7%, respectively. Among three cases that were false-negative by US, two were due only to microcalcification and all three were categorized as 2. The average tumor diameter in 16 cases that were false-negative by MMG was 12.9mm, and all were invasive cancers.
The present results indicate that the sensitivity of US is superior to that of MMG for diagnosis of breast cancer. Regular follow-up using US is thought to contribute to the early detection of small invasive cancers. US is complementary to MMG for detection of breast cancer, and therefore the two techniques together are thought to provide better screening sensitivity.
