Favorable surgical outcomes of aldosterone-producing adenoma based on lateralization by CT imaging and hypokalemia: a non-AVS-based strategy

Abstract

Purpose: To test the efficacy of a strategy based on CT imaging and clinical characteristics on lateralizing origin of excess aldosterone secretion in primary aldosteronism.

Patients and methods: Consecutive patients with diagnosed primary hyperaldosteronism from June 2006 to July 2012 in our center underwent adrenal surgeries without pre-operational adrenal venous sampling (AVS) if all the three criteria were met: (1) round- or oval-shaped occupational lesion of low density after contrast enhancement with diameter >1 cm on CT scan was located in one adrenal gland; (2) unequivocally normal contralateral adrenal gland; (3) serum potassium level lower than 3.5 mmol/L. Subjects who had received operation were taken into analysis and follow-ups.

Results: One hundred and twenty-five patients fulfilled the criteria and were recruited into our research. One hundred and twenty-two operated patients (97.6%) experienced complete resolution of hypokalemia as well as resolution or improvement in hypertension with reduction in antihypertensive medication, while 3 patients (2.4%) failed to obtain normal kalemia and continued on spironolactone therapy. At a median of 65-month (range 21-93) follow-up of these 122 subjects, 27 patients dropped out (22.1%). The 95 responding patients reported no episodes of paralysis or confirmed hypokalemia or any supplementation of potassium. Multivariate linear correlation analysis showed that plasma potassium level was correlated inversely with tumor diameter (r = -0.258, 95% CI -0.076, -0.514, p = 0.037) and basal plasma aldosterone level (r = -0.251, 95% CI -0.040, -0.464, p = 0.042).

Conclusions: Most patients with typical unilateral adrenal macroadenomas, normal contralateral glands and hypokalemia could attain favorable surgical therapeutic outcomes without pre-operational AVS lateralization.

Keywords: Adrenal venous sampling; Aldosterone-producing adenoma; Computed tomography; Lateralization; Outcome; Primary aldosteronism.