Radionuclide bone scan in initial staging of breast cancer.

Radionuclide bone scans of 100 patients with newly diagnosed breast cancer were retrospectively analysed. The number and topography of increased area of uptake were noted. Diagnosis criterion was defined by at least four foci of increased uptake, outside peripheral articular joints. In case of a number between one and three, the result was considered doubtful and radionuclide bone scan was confronted to available standard X Rays or/and radionuclide bone scan follow-up. Correlations of radionuclide bone scans with T, N and the clinical stage were assessed using chi-square methods. Metastases were present in 9 patients (9%). In five of these cases, the pattern was manifestly metastatic without the need to other investigation. In the other cases, interpretation required complementary investigation. The yield of metastases was very low in localized stages, this pointed out the difficulty in interpretation of radionuclide bone scans for localized stages, probably due to a less skeletal extension.