Evidence for selective use of bone scans in early stage breast cancer

To determine the usefulness of bone scans in detecting metastatic disease in women with early stage breast cancer, records of 193 patients who had bone scans preformed and underwent breast conservation therapy at a single institution were reviewed. Patients with invasive T1 or T2 breast carcinomas were eligible for this study; patients with a true positive bone scan were excluded from conservation therapy and, thus, were excluded from this study. The incidence of false positive bone scans in this study population was 32.6% (63/193 patients). Patients over 50 years of age had a significantly greater incidence of false positive bone scans (p<0.05). In the 63 patients with false positive bone scans, 101 radiographs were performed to exclude metastatic disease in areas of increased uptake identified on bone scan. No significant difference in the rate of false positive bone scans was seen in relation to tumor size, pathologic or clinical nodal status or hormone receptor activity of the primary tumor. Thus, selective use of bone scans is advocated in patients with early stage (T1 or T2) breast cancer.