TY - JOUR T1 - Intraindividual Comparison of <sup>99m</sup>Tc-Methylene Diphosphonate and Prostate-Specific Membrane Antigen Ligand <sup>99m</sup>Tc-MIP-1427 in Patients with Osseous Metastasized Prostate Cancer JF - Journal of Nuclear Medicine JO - J Nucl Med SP - 1373 LP - 1379 DO - 10.2967/jnumed.117.200220 VL - 59 IS - 9 AU - Hendrik Rathke AU - Ali Afshar-Oromieh AU - Frederik Lars Giesel AU - Christophe Kremer AU - Paul Flechsig AU - Sabine Haufe AU - Walter Mier AU - Tim Holland-Letz AU - Maximilian De Bucourt AU - Thomas Armor AU - John W. Babich AU - Uwe Haberkorn AU - Clemens Kratochwil Y1 - 2018/09/01 UR - http://jnm.snmjournals.org/content/59/9/1373.abstract N2 - The objective of this study was to evaluate the rate of detection of bone metastases obtained with the prostate-specific membrane antigen (PSMA)–targeting tracer 99mTc-MIP-1427, as opposed to conventional bone scanning with 99mTc-methylene diphosphonate (99mTc-MDP), in a collective of patients with known advanced-stage osseous metastasized prostate cancer. Methods: Twenty-one patients with known metastatic disease were staged with both conventional bone scanning and PSMA ligand scintigraphy within a time frame of less than 10 d. Imaging included planar whole-body scanning and SPECT or SPECT/CT with 2 bed positions 3 h after injection of either 500–750 MBq of 99mTc-MIP-1427 or 600–750 MBq of 99mTc-MDP. Lesions were scored as typical tumor, equivocal (benign/malignant), or normal within a standard reporting schema divided into defined anatomic regions. Masked and consensus readings were performed with sequential unmasking: planar scans first, then SPECT/CT, the best evaluable comparator (including MRI), PET/CT, and follow-up examinations. Results: Eleven patients had PSMA-positive visceral metastases that were predictably not diagnosed with conventional bone scanning. However, SPECT/CT was required to distinguish between soft-tissue uptake and overlapping bone. Four patients had extensive 99mTc-MDP–negative bone marrow lesions. Seven patients had superscan characteristics on bone scans; in contrast, the extent of red marrow involvement was more evident on PSMA scans. Only 3 patients had equivalent results on bone scans and PSMA scans. In 16 patients, more suspect lesions were detected with PSMA scanning than with bone scanning. In 2 patients (10%), a PSMA-negative tumor phenotype was present. Conclusion: PSMA scanning provided a clear advantage over bone scanning by reducing the number of equivocal findings in most patients. SPECT/CT was pivotal for differentiating bone metastases from extraosseous tumor lesions. ER -