Impact of continuous mineralocorticoid receptor antagonist treatment on the concordance between 68Ga-Pentixafor PET/CT and adrenal venous sampling in primary aldosteronism patients with a CT-detected unilateral adrenal adenoma

Current guidelines recommend discontinuing mineralocorticoid receptor antagonists (MRA) for at least four weeks prior to adrenal venous sampling (AVS) in patients with primary aldosteronism (PA). However, this is often unfeasible due to refractory hypertension or severe hypokalemia. 68 Ga-Pentixafor PET/CT may provide non-invasive functional information for adrenal lesions. This study evaluated the concordance between 68 Ga-Pentixafor PET/CT and AVS in patients with PA and a CT-detected unilateral adrenal adenoma, stratified by MRA exposure. We prospectively enrolled 98 patients with biochemically confirmed PA who underwent both successful bilateral AVS and 68 Ga-Pentixafor PET/CT. The primary analysis included 41 patients with a CT-detected unilateral adrenal adenoma who met the predefined radiological criteria: 21 receiving MRA therapy(MRA group) and 20 not receiving MRA therapy(Non-MRA group) before lateralization testing. We described baseline characteristics, lateralization concordance between 68 Ga-Pentixafor PET/CT and AVS, and postoperative clinical and biochemical outcomes separately for the MRA and Non-MRA groups. Baseline aldosterone and serum potassium levels were comparable between the MRA and Non-MRA groups, whereas direct renin concentration was significantly higher in the MRA group. For lateralization, an SUVmax cutoff of 7.60 yielded the maximum Youden index (0.907). The concordance between 68 Ga-Pentixafor PET/CT and AVS showed no significant difference between the Non-MRA and MRA groups (90.00% vs. 85.71%, P > 0.05). This high concordance remained consistent across stratifications by laterality and CT lesion diameter. Following laparoscopic surgery, the postoperative clinical and biochemical success rates (complete or partial) were 88.89% and 94.44% in the Non-MRA group, compared with 85.71% and 92.86% in the MRA group, respectively, with no significant differences observed between the two cohorts. In this selected cohort of PA patients with a CT-detected unilateral adrenal adenoma, 68 Ga-Pentixafor PET/CT showed high concordance with AVS, including among patients receiving MRA therapy. 68 Ga-Pentixafor PET/CT may serve as a complementary non-invasive tool in selected patients when AVS is challenging or medication withdrawal is clinically unsafe. ClinicalTrials.gov, NCT05188872. Registered 11 January 2022, https://clinicaltrials.gov/ct2/show/NCT05188872 .