Diagnosis of Bone Metastasis by Photoscanning With Strontium 85

Abstract

In 40 cancer patients with known or suspected metastases, strontium-85 photoscans showed good correlation with radiographic findings. Of 21 patients with radiographic changes in bone, the scan showed corresponding increments in strontium content in 18, irrespective of whether the x-ray lesions were osteolytic or osteoblastic. Three patients had positive scans despite absence of radiographic changes; biopsies of two of these revealed metastatic tumor in the scan-positive sites. Areas of abnormal strontium deposition were also noted in some patients with known bone metastases elsewhere, although no symptoms were present and x-rays appeared normal. The strontium-85 photoscan is useful also in depicting metastatic lesions in areas difficult to visualize on routine x-ray films, such as the sternum and scapula.