Imaging CXCR4 expression in patients with suspected primary hyperaldosteronism

Area of Science:

• Nuclear Medicine
• Radiopharmacology
• Endocrinology

Background:

• Differentiating unilateral aldosterone-producing adenoma (APA) from bilateral idiopathic adrenal hyperplasia (IAH) and nonfunctional adrenal adenoma (NFA) is crucial in managing primary aldosteronism (PA).
• Previous ex vivo studies indicated CXC chemokine receptor type 4 (CXCR4) expression as a potential biomarker for APA detection.
• Clinical evaluation of CXCR4 imaging using ⁶⁸Ga-pentixafor PET/CT is needed to assess its diagnostic utility in vivo.

Purpose of the Study:

• To clinically evaluate the efficacy of ⁶⁸Ga-pentixafor PET/CT imaging for detecting and differentiating APA in patients with suspected PA.
• To assess the sensitivity, specificity, and accuracy of ⁶⁸Ga-pentixafor PET/CT in identifying APA compared to histopathology and clinical assessment.

Main Methods:

• Prospective recruitment of 36 patients with clinical suspicion of PA.
• All patients underwent ⁶⁸Ga-pentixafor PET/CT imaging.
• Analysis included visual assessment of tracer uptake, semi-quantitative measurements (SUV_max, LLR, LCR), and correlation with histopathology and clinical follow-up.

Main Results:

• ⁶⁸Ga-pentixafor PET/CT demonstrated high diagnostic performance with 100% sensitivity, 78.6% specificity, and 92.3% accuracy in distinguishing APA.
• Significantly higher SUV_max values were observed in APA lesions compared to non-APA lesions (P < 0.0001).
• Optimal thresholds for SUV_max, LCR, and LLR were established, providing high sensitivity and specificity for APA prediction.

Conclusions:

• ⁶⁸Ga-pentixafor PET/CT is a valuable non-invasive tool for detecting APA in patients with primary aldosteronism.
• The imaging technique aids in differentiating APA from other adrenal pathologies, potentially improving diagnostic accuracy and patient management.