Diagnosing mammary cancer among an unselected Finnish population. Proposal for practical improvements

A total of 309 new mammary cancer patients were found in three successive years among 250,000 unselected Finns showing an annual rate of 1.08 cancers per 1000 women over 20 years of age. The main preoperative examinations were palpation and mammography. Palpation alone was performed preoperatively in 158 (51 percent) patients, palpation and mammography in 120 (38 percent), and the tumor was nonpalpable and found only in mammography in 31 (10 percent) patients. Fine-needle biopsy with palpation was performed in 191 (62 percent) patients and it confirmed definite malignancy in 89 cases, that is in 47 percent of the biopsied patients and in 29 percent of all patients. Mammography was most valuable in small tumors and fine-needle biopsy in large ones. The number of mammographies performed in the whole population per each new cancer case was 50; it seems unreasonable to increase the number of mammographies performed. It seems that the best way to improve the present preoperative evafuation of mammary cancer patients would be to perform a fine-needle biopsy under stereotactic guidance in every patient, and especially in those with a small tumor.