THE USEFULNESS OF BONE-SCINTIGRAPHY WITH SPECT IMAGES FOR DETECTION OF PULMONARY METASTASES FROM OSTEOSARCOMA

OBJECTIVE. We prospectively compared the ability of two techniques-bon e scintigraphy with single-photon emission computed tomography (SPECT) of the chest and CT of the chest-to reveal potential osteosarcoma met astases of the lung. SUBJECTS AND METHODS. Our study included 27 patie nts with osteosarcoma who prospectively underwent both bone scintigrap hy with SPECT of the chest and CT of the chest. The imaging results we re compared with outcome or pathologic analysis of any lung lesions fo und. RESULTS. Eight (30%) of the 27 patients had pulmonary metastases. Four of these eight patients had positive results on both CT studies and bone SPECT studies, with additional lesions detected with bone SPE CT in two of these four patients. The other four patients with pulmona ry metastases had positive results on CT studies, whereas the results of bone SPECT studies remained negative. The results of bone SPECT stu dies were negative in the 19 patients without pulmonary metastases. CT , however, showed abnormalities in seven (37%) of the 19 patients, whi ch were eventually attributed to benign conditions. CONCLUSION, Negati ve results on a bone SPECT study of the chest should not be used to ex clude the possibility of lung metastases. However, if the results are positive, a bone SPECT study can be used to confirm abnormalities seen on CT scans and may also reveal subtle lesions missed on CT scans.