99mTc-antigranulocyte bone marrow scintigraphy of breast and prostate skeletal metastases

Although bone scintigraphy using Tc-99m labelled diphosphonates is a highly sensitive modality for the detection of of the extent of secondary skeletal malignancies, it is often not sufficient since possible bone marrow participation cannot be imaged We make a preliminary report on the usefulness of bone marrow immunoscintigraphy in the follow-up of patients with skeletal metastases due to breast and prostate cancer in parallel with the interpretation of conventional Tc-99m MDP bone scans. Approximately 7 to 9 months after radionuclide therapy both Tc-99m MDP [Hellenic Nuclear Research Center "Democritos". Aghia Paraskevi, Attikil and Tc-99m Anti-Granulocyte BW 250/183 [CIS Bio International, Gif sur Yvette, France] bone scans were performed on 2 prostate cancer patients and 5 women with breast cancer with disseminated bone metastases. Bone scans preceded bone marrow scans. Bone marrow defects were concordant with cortical scans in 4 cases, while they were larger in 4 sites compared to -MDP scan. Four sites in the ribs, shown on -MDP scan could not be detected on antigranulocyte scans. Bone cortex and marrow combined imaging of osseous metastases using different radiotracers increases the information on the real extent of skeletal involvement; the scintigraphic data obtained are valuable for the further decision making for the best possible management of unexpected myelosuppressive side effects as well as the follow-up of the treated cancer patients.