68Ga-Pentixafor PET/CT for diagnosing surgically curable primary aldosteronism concurrent with autonomous cortisol secretion.

OBJECTIVE

For primary aldosteronism concurrent with autonomous cortisol secretion (PA/ACS), localization of the aldosterone-producing lesion is a challenge due to potential cortisol interference. To evaluate the accuracy of 68Ga-Pentixafor PET/CT for unilateral primary aldosteronism in PA/ACS.

METHODS

This retrospective study included primary aldosteronism patients concurrent with (PA/ACS) or without (isolated primary aldosteronism) ACS who underwent both 68Ga-Pentixafor PET/CT and adrenal vein sampling (AVS). In PA/ACS, both cortisol and metanephrine-corrected indices in AVS were calculated. According to the final subtyping diagnosis based on post-surgery outcomes, the accuracy of 68Ga-Pentixafor PET/CT and AVS for unilateral primary aldosteronism was calculated.

RESULTS

One hundred thirty-two isolated primary aldosteronism and 34 PA/ACS patients were included. In isolated primary aldosteronism, 78 (59.1%) and 83 (62.9%) were identified as unilateral primary aldosteronism by AVS and 68Ga-Pentixafor PET/CT, respectively. Of the 74 patients receiving surgery, 71 achieved complete biochemical remission. The accuracy of AVS and 68Ga-Pentixafor PET/CT in predicting unilateral primary aldosteronism was 81.1% (60/74) and 77.0% (57/74), respectively. In the PA/ACS, 15 (44.1%), 18 (52.9%) and 16 (47.1%) were identified as unilateral primary aldosteronism by cortisol-corrected AVS, metanephrine-corrected AVS and 68Ga-Pentixafor PET/CT, respectively. Of the 17 patients receiving surgery, 15 achieved complete biochemical remission. The accuracy of cortisol, metanephrine-corretced AVS, and 68Ga-Pentixafor PET/CT in predicting unilateral primary aldosteronism was 64.7% (11/17), 76.5% (13/17), and 76.5% (13/17), respectively. In both groups, a combined diagnostic strategy - classifying unilateral primary aldosteronism when either AVS or PET/CT is positive - achieves a higher accuracy of 88.2-95.9%.

CONCLUSION

While AVS remains a valuable tool for primary aldosteronism subtyping, 68Ga-Pentixafor PET/CT demonstrates non-inferior performance to AVS in identifying unilateral primary aldosteronism in PA/ACS patients, and integrating 68Ga-Pentixafor PET/CT with AVS may enhance patient selection for surgery.