Evaluation of bone scan in preoperative clinical staging of breast cancer.

Two hundred and thirty-five patients underwent a bone scan prior to, or within two weeks of, instituting surgical treatment for cancer of the breast. These patients were staged clinically according to the TNM classification. There were three patients with abnormal bone scans of a total of 173 patients in clinical stages I and II; none of 86 patients had stage I disease and only three of 87 patients had stage II disease. The conclusion from the study is that routine preoperative bone scans are of no value for staging purposes in patients with clinical stage I disease. In clinical stage II, bone scans are difficult to justify, considering the low yield (3.4%) and the cost per abnormal scan.