Diagnostic tests in breast cancer. Clinical strategies based on diagnostic probabilities.

Optimal diagnostic strategies used in screening for breast cancer and evaluating breast masses depend on the likelihood of malignancy, findings at physical examination, and the accuracy of tests and procedures. Results from published series, in conjunction with calculations of the probability of malignancy based on test results, indicate that only mammography is needed for screening. A clinical sequence for evaluating palpable breast masses should include a combination of mammography, ultrasound examination, and needle aspiration. In patients with negative findings, the probability of cancer will be sufficiently low to obviate the need for immediate surgical biopsy. However, if there are positive findings, or the initial clinical likelihood of malignancy is high, excision of the mass is indicated.