Impact of abnormal uptakes in bone scan on the prognosis of patients with lung cancer

The detection of bone metastases is important in the management of patients with lung cancer because bone metastasis has a major impact on the prognos is and choice of treatment modality. Bone scan has been widely used for ear ly detection of bone metastases but its low specificity complicates confirm ation of bone scan findings. To evaluate the effects of abnormal bone scan findings on the prognosis of patients with lung cancer, we retrospectively analyzed the effect of abnormal uptakes on the prognosis of patients with p rimary lung cancer. The overall survival of patients with abnormal bone upt ake was not significantly different from those without abnormal uptake. How ever, the patients with more than two abnormal bone uptakes had significant ly shorter survival than those with no abnormal uptake (P < 0.05). To confi rm the effect of abnormal bone uptakes on survival, we compared the surviva l curves of three patient groups without knowledge of bone scan findings: g roup A, stage I-IIIB with more than two abnormal bone uptakes (potential st age IV); group B, stage IIIB with no abnormal bone uptake (true stage IIIB) ; and group C, stage IV with no abnormal bone uptake. Group A revealed shor ter survival than group B (P < 0.05). But, there was no significant differe nce in survival times between group A and group C. In the Cox regression an alysis, the presence of more than two abnormal bone uptakes was a significa nt prognostic factor (P = 0.0277), together with performance status, stage, and albumin. These results suggest that one or two abnormal bone uptake at diagnosis did not affect overall survival of the patients, and that the pa tients with more than two abnormal bone uptakes are considered as clinical stage IV because of high probability of bone metastases. (C) 2000 Elsevier Science Ireland Ltd. All rights reserved.