Abstract
Breast cancer screening was carried out at our institution in a “Human Dock” style health check, by inspection and palpation, together with ultrasonography. Breast cancers detected were reviewed and the utility of ultrasonography was evaluated. A total of 14,063 women underwent the screening and the results were good, with a recall rate of 3.4%, a cancer detection rate of 0.30%, and a positive predictive value of 8.7%. Of 42 breast cancers detected by ultrasonography, 30 (71%) were 1.5cm or less in diameter. For breast cancers detected by inspection and palpation, the detection rate for small cancers measuring 1.5cm or less was 33% (10 out of 30 women), and 100% (12 women) for tumors measuring more than 1.5cm. The cancer detection rate by mammography was 39% (9 out of 23 cancers) for tumors measuring 1.5cm or less, and 91% (10 out of 11 cases) for those larger than 1.5cm. Thus cancer detection by ultrasonography was optimal for tumors measuring 1.5cm or less. Histologically proven lymph node metastasis was positive in 8 (25%) of 32 patients, among whom some had primary cancers measuring 1.5cm or less.
Tumor volume doubling time (TVDT) was measurable in 10 women ; there was no change in size in one instance, and in the others TVDT was 4.8 to 32.5 months (mean 15.5 months), small cancers approximately 1cm in size having a long TVDT. In women whose cancer size could be determined twice or more, TVDT tended to be short when a cancer measured about 1cm or more. Cancers with a long TVDT showed low histological malignancy, and thus detection of breast cancers with a long TVDT at screening appears to be rewarding.
