Implications of the 99mTc diphosphonate bone scan on treatment of primary breast cancer.

The 99mTc diphosphonate scan is important in the study of primary breast cancer. The short-term prognosis for scan-positive patients is poor. Serial bone scans provide a safe and reliable prognostic index in patients following mastectomy. By correlating the scan with biochemical tumor markers, a matrix of diagnostic tests may be developed that is capable of identifying high-risk patients who may benefit from systemic therapy.