Bone scanning with 99m-Tc-phosphates: a comparison and problems in the detection of tumor metastasis.

A comparative study on 99m-Tc-phosphate compounds (TcPP) in detecting tumor metastasis to bone and problems accompanying it are reported. TcPP revealed metastatic foci which are unrecognized by conventional bone survey. To recognize these foci, exclusion of following problems is necessary: Accumulation at front of neck, asymmetrical image of joint, increased bone density of the aged, Tc-photon absorption and radiotherapy effect. The mechanism of TcPP accumulation is discussed.