Non-tumor sparing bilateral adrenalectomy for bilateral aldosterone-producing adenomas; AVS-based approach

Presentation Number: SAT-66
Date of Presentation: June 15th, 2013

Ryo Morimoto*1, Masataka Kudo1, Yoshitsugu Iwakura1, Ken Matsuda1, Yoshikiyo Ono1, Masahiro Nedzu2, Kazumasa Seiji1, Kei Takase1, Yoichi Arai1, Yasuhiro Nakamura1, Hironobu Sasano1, Sadayoshi Ito1 and Fumitoshi Satoh1
1Tohoku University Hospital, Sendai, Japan, 2Tohoku University Hospital

Abstract

Background: Primary aldosteronism (PA) due to bilateral aldosterone-producing adenomas is considered to be one of surgically curable subtypes. Bilateral adrenal tumors detected by computed tomography scan in patiens with PA should be functionally differentiated between 'aldosterone-producing adenoma (APA)' and clinically non-functioning adenoma. We therefore performed adrenal venous sampling (AVS) to show aldosterone hypersecretion from drainage veins of 'APA' and suppressed secretion of aldosterone from non-tumor adrenal drainers, which makes it possible to preoperative diagnosis of bilateral APA, but not bilateral hyperplasia with clinically non-functioning bilateral adenomas.

Clinical case: Three patients (two males) were referred to investigate PA with bilateral adrenal nodules. Mean age and blood pressure were 50+/-1.53 years and 151.3/96.7 mmHg, respectively with anti-hypertensive medication. Mean baseline aldosterone and plasma renin activity (PRA) were 14.3 ng/dl and 0.40 ng/ml/h, respectively, and captopril challenge tests showed mean ARR of 67.6 ng/dl per ng/ml/h, while 1mg overnight dexamethasone suppression tests confirmed no autonomous secretion of cortisol in all cases. CT showed bilateral adrenal nodules with mean size of 10.7 mm of right and 8.0 mm of left. In AVS, we defined hypersecretion of aldosterone as higher aldosterone/cortisol ratio obtained from tumor drainer than that from peripheral vein, while we regarded lower aldosterone/cortisol ratio obtained from non-tumor drainer as suppressed secretion of aldosterone from attached non-tumor adrenal tissues. AVS of the three cases showed hypersecretion of aldosterone from each tumor drainer and suppressed aldosterone secretion from non-tumor drainer, which seemed consistent with clinical diagnosis of bilateral APA. Based on both AVS and CT findings, non-tumor adrenal sparing bilateral adrenalectomy was performed, and histopathological diagnosis was confirmed. Postoperative evaluation showed mean aldostereone and PRA were 3.67 and 0.75, respectively and temporary replacement of glucocorticoid was withdrawn in all cases with mean duration of 249 days. After surgery, hypertension was so improved that one patient became free from medication and the others reduced the number of anti-hypertensives to one each.

Conclusion: Bilateral APA could be preoperatively differentiated from bilateral hyperplasia with bilateral adrenal nodules by AVS with specific sampling from drainers of both APA and non-tumor attached adrenal tissue.

 

Nothing to Disclose: RM, MK, YI, KM, YO, MN, KS, KT, YA, YN, HS, SI, FS