Laparoscopic enucleation of macronodules in a patient with ACTH-independent macronodular adrenal hyperplasia 7 years after unilateral adrenalectomy: consideration of operative procedure

Clinical, pathophysiologic, genetic and therapeutic progress in Primary Bilateral Macronodular Adrenal Hyperplasia

Patients with primary bilateral macronodular adrenal hyperplasia (PBMAH) usually present bilateral benign adrenocortical macronodules at imaging and variable levels of cortisol excess. PBMAH is a rare cause of primary overt Cushing's syndrome, but may represent up to one third of bilateral adrenal incidentalomas with evidence of cortisol excess. The increased steroidogenesis in PBMAH is often regulated by various G-protein coupled receptors aberrantly expressed in PBMAH tissues; some receptor ligands are ectopically produced in PBMAH tissues creating aberrant autocrine/paracrine regulation of steroidogenesis. The bilateral nature of PBMAH and familial aggregation, led to the identification of germline heterozygous inactivating mutations of the ARMC5 gene, in 20-25% of the apparent sporadic cases and more frequently in familial cases; ARMC5 mutations/pathogenic variants can be associated with meningiomas. More recently, combined germline mutations/pathogenic variants and somatic events inactivating the KDM1A gene were specifically identified in patients affected by GIP-dependent PBMAH. Functional studies demonstrated that inactivation of KDM1A leads to GIP-receptor (GIPR) overexpression and over or down-regulation of other GPCRs. Genetic analysis is now available for early detection of family members of index cases with PBMAH carrying identified germline pathogenic variants. Detailed biochemical, imaging, and co-morbidities assessment of the nature and severity of PBMAH is essential for its management. Treatment is reserved for patients with overt or mild cortisol/aldosterone or other steroid excesses taking in account co-morbidities. It previously relied on bilateral adrenalectomy; however recent studies tend to favor unilateral adrenalectomy, or less frequently, medical treatment with cortisol synthesis inhibitors or specific blockers of aberrant GPCR.

Laparoscopic Subcutaneous Transposition of a Pedicled Adrenal for ACTH-Independent Bilateral Macronodular Adrenal Hyperplasia

BACKGROUND AND PURPOSE

Bilateral adrenalectomy or unilateral adrenalectomy and contralateral partial adrenalectomy are indicated for the treatment of ACTH-independent macronodular adrenal hyperplasia. Independent of the surgical procedure, the prognosis is poor. This article discusses a new treatment method and its efficacy for treating nodular adrenal hyperplasia.

METHODS

We performed a retrospective review of the medical records of 12 patients operated on between January 2008 and October 2014 at the First Affiliated Hospital of Zhengzhou University. All patients were treated by laparoscopic subcutaneous transposition of a pedicled adrenal. We performed postoperative monitoring of patients, including clinical symptoms and 24-hour levels of serum-free and urinary-free cortisol.

RESULTS

All 12 patients were pathologically confirmed to have nodular adrenal hyperplasia and were followed for an average of 45.5 months (range 24-60 months). The clinical symptoms of all patients disappeared, and the 24-hour plasma-free cortisol and urinary-free cortisol levels were within the normal range.

CONCLUSIONS

Laparoscopic subcutaneous transposition of a pedicled adrenal is a new and effective method for treating bilateral macronodular adrenal hyperplasia and can achieve long-term remission of Cushing's syndrome.

Comparison of Retroperitoneoscopic and Transperitoneal Laparoscopic Adrenalectomy for Right-Sided Benign Tumors: A Single-Institute Experience

<b><i>Introduction:</i></b> There is a lack of data regarding the appropriateness of transperitoneal and retroperitoneal approaches for right-sided laparoscopic adrenalectomy. The aim of this study was to determine whether there is any difference between right-sided transperitoneal laparoscopic adrenalectomy (TLA) and retroperitoneal laparoscopic adrenalectomy (RLA). <b><i>Material and Methods:</i></b> Our surgery database was reviewed to identify patients who underwent right-sided laparoscopic adrenalectomy with a retroperitoneal or transperitoneal approach since 2000. Fifty-five patients were enrolled (31 RLA and 24 TLA). Patient characteristics, as well as operative and perioperative details, were compared between the two groups. <b><i>Results:</i></b> There was no difference in patient characteristics between the groups. There was a statistically significant difference (p = 0.02) in blood loss (31.7 ± 16.4 vs. 56.9 ± 65.5 ml) between RLA and TLA when the patient's BMI was >26. There was no significant difference in operative time, conversion to open surgery, length of hospitalization, or time to oral intake between the groups. <b><i>Conclusions:</i></b> Right-sided laparoscopic adrenalectomy can be performed safely and effectively via either RLA or TLA. Surgeons can adopt either approach with confidence depending on their preference if they are familiar with that approach.

Marked cortisol production by intracrine ACTH in GIP-treated cultured adrenal cells in which the GIP receptor was exogenously introduced

The ectopic expression of the glucose-dependent insulinotropic polypeptide receptor (GIPR) in the human adrenal gland causes significant hypercortisolemia after ingestion of each meal and leads to Cushing’s syndrome, implying that human GIPR activation is capable of robustly activating adrenal glucocorticoid secretion. In this study, we transiently transfected the human GIPR expression vector into cultured human adrenocortical carcinoma cells (H295R) and treated them with GIP to examine the direct link between GIPR activation and steroidogenesis. Using quantitative RT-PCR assay, we examined gene expression of steroidogenic related proteins, and carried out immunofluorescence analysis to prove that forced GIPR overexpression directly promotes production of steroidogenic enzymes CYP17A1 and CYP21A2 at the single cell level. Immunofluorescence showed that the transfection efficiency of the GIPR gene in H295R cells was approximately 5%, and GIP stimulation enhanced CYP21A2 and CYP17A1 expression in GIPR-introduced H295R cells (H295R-GIPR). Interestingly, these steroidogenic enzymes were also expressed in the GIPR (–) cells adjacent to the GIPR (+) cells. The mRNA levels of a cholesterol transport protein required for all steroidogenesis, StAR, and steroidogenic enzymes, HSD3β2, CYP11A1, CYP21A2, and CYP17A1 increased 1.2-2.1-fold in GIP-stimulated H295R-GIPR cells. These changes were reflected in the culture medium in which 1.5-fold increase in the cortisol concentration was confirmed. Furthermore, the levels of adenocorticotropic hormone (ACTH) receptor and ACTH precursor proopiomelanocortin (POMC) mRNA were upregulated 2- and 1.5-fold, respectively. Immunofluorescence showed that ACTH expression was detected in GIP-stimulated H295R-GIPR cells. An ACTH-receptor antagonist significantly inhibited steroidogenic gene expression and cortisol production. Immunostaining for both CYP17A1 and CYP21A2 was attenuated in cells treated with ACTH receptor antagonists as well as with POMC siRNA. These results demonstrated that GIPR activation promoted production and release of ACTH, and that steroidogenesis is activated by endogenously secreted ACTH following GIP administration, at least in part, in H295R cells.