177 Lu-PSMA radioligand therapy of predominant lymph node metastatic prostate cancer 177Lu-PSMA radioligand therapy of predominant lymph node metastatic prostate cancer

The aim of this study was to determine the role of fluorine-18-choline (18F-FCH) PET/CT in comparison with technetium-99m-methoxyisobutylisonitrile (99mTc-MIBI) single-photon emission computed tomography/computed tomography (SPECT/CT) in primary hyperparathyroidism and to investigate whether maximum standardized uptake value (SUVmax) may be indicative of disease severity. Thirty-five primary hyperparathyroidism patients (24 females, 11 males, mean age: 55.31±12.27, range: 25–72 years) who underwent 99mTc-MIBI SPECT/CT and 18F-FCH PET/CT and had inconclusive neck ultrasonography (USG) were studied. The diagnostic power of both modalities and the relationship between SUVmax and biochemical [serum parathormone (PTH), calcium, phosphorus, vitamin D3 levels, urinary calcium excretion/24 h] and clinical (bone mineral densitometry and urinary USG results) parameters were analyzed. In 29 of 35 patients, 99mTc-MIBI SPECT/CT and 18F-FCH were concordant (κ=0.64, P=0.001). In five of 35 patients with a negative SPECT/CT, 18F-FCH PET/CT accurately localized parathyroid adenomas. In one patient, 18F-FCH was false negative and 99mTc-MIBI SPECT/CT showed the lesion. The sensitivity, specificity, positive predictive value, negative predictive value, and accuracy of 99mTc-MIBI SPECT/CT and 18F-FCH PET/CT were calculated to be 78, 100, 100, 70, 86%, and 96, 100, 100, 93, and 97%, respectively. SUVmax was correlated with lumbal T scores (P=0.026). The mean serum PTH levels were significantly higher (P=0.026) and lumbal and femur T scores were significantly lower (P=0.04 and 0.008) in patients with SUVmax greater than 4.4 (i.e. the mean SUVmax calculated in positive cases). 18F-FCH PET/CT has a high diagnostic power in primary hyperparathyroidism and can be used for further evaluation of patients with inconclusive neck USG and 99mTc-MIBI SPECT/CT. SUVmax of the hyperfunctioning parathyroid gland seems to be predictive of disease severity in terms of serum PTH and bone mineral densitometry results. Studies with larger patient groups are needed to support these data.

Diagnostic and Interventional Radiology

To test the hypothesis that, in the initial evaluation of patients with suspected coronary artery disease (CAD), stress myocardial perfusion imaging (MPI) would result in less downstream testing than coronary computed tomographic angiography (CCTA).

The aim of the review was to evaluate patient and treatment characteristics for patients with metastatic castration-resistant prostate cancer (mCRPC) treated with PSMA radioligand therapy (PRLT) associated with above-average outcome. The systematic review and meta-analysis followed recommendations by the Preferred Reporting Items for Systematic reviews and Meta-Analysis (PRISMA). We searched for publications in PubMed, Embase, and ClinicalTrials.gov up to 31 September 2020. Thirty-six publications and four duplicates reported 2346 patients. Nearly two-thirds of the patients had bone metastases. Median overall survival (OS) was 16 months. Asymptomatic patients and patients with only lymph node metastases lived longer than symptomatic patients and patients with more extensive metastases. Patients treated with an intensified schedule of ¹⁷⁷Lu PRLT lived longer than those treated with a conventional schedule. Half of the patients obtained a PSA decline ≥ 50% and these patients lived longer than those with less PSA decline. Approximately 10% of the patients developed hematologic toxicity with anemia grade 3 as the most severe adverse effect. Characteristics for patients, cancer, restaging, and PRLT predict above average overall survival following treatment with PRLT.