Background: Bone scans are often performed as routine staging procedures for patients with T1 and T2 breast cancers. Bone scanning in this patient population is evaluated with respect to cost and impact on clinical management.
Methods: Three hundred sixteen women with clinical T1 or T2 breast cancer who had bone scans were treated at Fox Chase Cancer Center from January of 1991 to December of 1992. We reviewed clinical and pathologic tumor stage, nodal status, laboratory studies, symptoms, bone scans (frequency, results, and cost), and resultant studies.
Results: Sixty-three women (20%) had bone scans that were interpreted as positive or suspicious for metastatic disease on initial presentation, resulting in 105 confirmatory studies, including 80 plain films, 10 computed tomography (CT) scans, 11 magnetic resonance imaging (MRI) scans, and four biopsies. Seven patients (2%) had skeletal metastases, six of whom had clinical stigmata of distant disease. A single patient (0.3%), with no signs or symptoms of distant disease, had bone metastases. The initial bone scans cost $224,676; additional tests cost another $53,122. The initial positive predictive value of bone scans in detecting metastatic disease was 11%. The "baseline" bone scans were followed by 130 "follow-up" scans over 2 years at a cost of $92,400. Seven patients developed metastatic disease, confirmed by 31 additional studies. Again, only one patient was asymptomatic. The availability of initial studies for comparison did not prevent thorough evaluation in women with worrisome follow-up bone scans.
Conclusions: Bone scans of 316 woman at initial presentation with T1 or T2 breast cancer identified one incurable patient whose management was changed. The cost was $277,798. Bone scans contribute little information to the management of asymptomatic patients.