[en] Bone scans using technetium phosphate complexes were performed on 874 patients with breast cancer referred to the South Wales Radiotherapy Centre between January 1973 and December 1976. Most of the patients also had radiological skeletal surveys performed within one month of the scan. Scans proved to be more reliable and sensitive than X-rays for detection of bone metastases. 20% of all patients with clinically localised disease had positive scans, bone metastases were confirmed within two years in four-fifths of the patients with positive scans and negative X-rays. It is suggested that a patient with an abnormal scan should not receive radical local treatment. (author)