Accuracy of Gallium-68 Pentixafor Positron Emission Tomography-Computed Tomography for Subtyping Diagnosis of Primary Aldosteronism

Adrenal vein sampling (AVS) is the recommended procedure for subtyping primary aldosteronism (PA) as unilateral PA (UPA) or bilateral PA (BPA), with different treatment needed for each: adrenalectomy for UPA and medication for BPA. However, AVS is invasive and technically difficult, and how to subtype PA noninvasively is currently a great challenge. To evaluate the accuracy of gallium-68 pentixafor positron emission tomography-computed tomography (PET-CT) in subtyping PA using AVS as a reference standard. This diagnostic study was conducted at a tertiary hospital in China among patients diagnosed with PA. Enrollment was started in November 2021, with follow-up ending in May 2022. : Patients were recruited to undergo gallium-68 pentixafor PET-CT and AVS. Maximum standardized uptake value (SUVmax) of each adrenal gland during PET-CT was measured to calculate the lateralization index of SUVmax. Area under the receiver operating characteristic curve (AUROC), specificity, and sensitivity were used to analyze the accuracy of the lateralization index based on SUVmax for subtyping PA. Among 100 patients with PA who completed the study (47 female [47.0%] and 53 male [53.0%]; median [IQR] age, 49 [38-56] years), 43 individuals had UPA and 57 individuals had BPA. Aldosterone-cortisol ratio (Spearman ρ = 0.26; P