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Metastasis-directed therapy (MDT) has been tested in clinical trials as a treatment option for oligorecurrent prostate cancer (PCa). However, there is an ongoing debate regarding the impact of using different imaging techniques interchangeably for defining lesions and guiding MDT within clinical trials. Methods: We retrospectively identified oligorecurrent PCa patients who had 5 or fewer nodal, bone, or visceral metastases detected by choline or prostate-specific membrane antigen (PSMA) PET/CT and who underwent MDT stereotactic body radiotherapy with or without systemic therapy in 8 tertiary-level cancer centers. Imaging-guided MDT was assessed as progression-free survival (PFS), time to systemic treatment change due to polymetastatic conversion (PFS2), and overall survival predictor. Propensity score matching was performed to account for clinical differences between groups. Results: Of 402 patients, 232 (57.7%) and 170 (42.3%) underwent MDT guided by [ 18 F]fluorocholine and PSMA PET/CT, respectively. After propensity score matching, patients treated with PSMA PET/CT-guided MDT demonstrated longer PFS (hazard ratio [HR], 0.49 [95% CI, 0.36-0.67]; P < 0.0001), PFS2 (HR, 0.42 [95% CI, 0.28-0.63]; P < 0.0001), and overall survival (HR, 0.39 [95% CI, 0.15-0.99]; P < 0.05) than those treated with choline PET/CT-guided MDT. Additionally, we matched patients who underwent [ 68 Ga]Ga-PSMA-11 versus [ 18 F]F-PSMA-1007 PET/CT, observing longer PFS and PFS2 in the former subgroup (PFS: HR, 0.51 [95% CI, 0.26-1.00]; P < 0.05; PFS2: HR, 0.24 [95% CI, 0.09-0.60]; P < 0.05). Conclusion: Diverse imaging methods may influence outcomes in oligorecurrent PCa patients undergoing MDT. However, prospective, head-to-head studies, ideally incorporating a randomized design, are necessary to provide definitive evidence and facilitate the practical application of these findings., (© 2024 by the Society of Nuclear Medicine and Molecular Imaging.)

Unlabelled: This study evaluated the accuracy of (99m)Tc-sestamibi scintigraphy and neck ultrasonography in patients with primary hyperparathyroidism (PHPT) and the role of intraoperative hand-held gamma-probes in minimally invasive radioguided surgery (MIRS) of patients with a high likelihood of a solitary parathyroid adenoma (PA). The study was undertaken under the aegis of the Italian Study Group on Radioguided Surgery and Immunoscintigraphy (GISCRIS)., Methods: Clinical records were reviewed for 384 consecutive PHPT patients undergoing radioguided surgery using a low dose of (99m)Tc-sestamibi. Selection of patients for MIRS instead of traditional bilateral neck exploration was based on preoperative imaging indicating a solitary PA. (99m)Tc-Sestamibi (37-110 MBq, or 1-3 mCi) was injected in the operating theater 10-30 min before the start of the intervention. Either 11-mm collimated (309 patients) or 14-mm collimated (75 patients) gamma-probes were used. Intraoperative quick parathyroid hormone (IQPTH) assay was used on 308 patients (80.2%)., Results: MIRS was successfully performed on 268 (96.8%) of 277 patients. Conversion to bilateral neck exploration was necessary in 9 patients (3.3%) because of either persistently high IQPTH levels after removal of the preoperatively visualized PA (4 patients), intraoperative frozen-section diagnosis of parathyroid carcinoma (2 patients), or hard-to-remove PA (3 patients). MIRS, which was performed under locoregional anesthesia in 72 patients, required a mean operating time of 37 min and a mean hospital stay of 1.2 d. MIRS was successfully performed also on 32 (78.0%) of 41 patients who had previously undergone thyroid or parathyroid surgery. No major surgical complications were observed in the MIRS group, and there were only 24 cases (11%) of transient postoperative hypocalcemia. The probe was of little help in patients with concomitant (99m)Tc-sestamibi-avid thyroid nodules and not helpful at all in patients with negative scan findings preoperatively. IQPTH measurement helped to disclose some cases of multigland parathyroid disease., Conclusion: (99m)Tc-Sestamibi scintigraphy, especially if combined with neck ultrasonography, is highly accurate in selecting PHPT candidates for MIRS. The low-dose (99m)Tc-sestamibi protocol (which entails a low-to-negligible radiation exposure to the surgical team) is safe and effective for MIRS. MIRS plays a limited role in patients with concomitant (99m)Tc-sestamibi-avid thyroid nodules and should be discouraged in patients with negative (99m)Tc-sestamibi finding preoperatively. IQPTH can be recommended during MIRS to facilitate intraoperative identification of previously undiagnosed multigland parathyroid disease.