Outcome and long-term follow-up of adrenal lesions in multiple endocrine neoplasia type 1

Adrenocortical tumors and hereditary syndromes

INTRODUCTION

Adrenocortical tumors (ACTs) are frequently encountered in clinical practice. They vary in clinical and biological characteristics from nonfunctional to life threatening hormone excess, from benign to highly aggressive malignant tumors. Most ACTs appear to be benign and nonfunctioning. It has been controversial how these apparently benign and nonfunctioning tumors should be monitored. Over the past few decades, significant advances have been made in understanding the regulation of growth and tumorigenesis in adrenocortical cells. Defining the molecular pathomechanisms in inherited tumor syndromes led to the expansion of research to sporadic ACTs. Distinct molecular signatures have been identified in sporadic ACTs and a potential genomic classification of ACT has been proposed.

AREAS COVERED

In this review, we discuss the various adrenocortical pathologies associated with hereditary syndromes with special focus on their molecular pathomechanisms, the understanding of which is important in the era of precision medicine.

EXPERT OPINION

Identifying the molecular pathomechanisms of the adrenocortical tumorigenesis in inherited syndromes has led to the understanding of the alterations in different signaling pathways that help explain the wide variations in the biology and behavior of ACTs.

Beyond the three P's: adrenal involvement in MEN1

Adrenal lesions (ALs) are often detected in patients with multiple endocrine neoplasia type 1 (MEN1). However, they are not well described in MEN1, making their clinical management unclear. This study examined the prevalence and outcomes of ALs found in MEN1. We performed a retrospective chart review of patients diagnosed with MEN1 from 1990 to 2021. ALs were diagnosed using abdominal or thoracic imaging and classified as being unilateral or bilateral, having single or multiple nodules, and as having diffuse enlargement or not. Measurable nodular lesions were analyzed for their size and growth over time. Patients' clinical and radiographic characteristics were collected. We identified 382 patients with MEN1, 89 (23.3%) of whom had ALs. The mean age at detection was 47 ± 11.9 years. We documented 101 measurable nodular lesions (mean size, 17.5 mm; range, 3-123 mm). Twenty-seven nodules (26.7%) were smaller than 1 cm. Watchful waiting was indicated in 79 (78.2%) patients, of whom 28 (35.4%) had growing lesions. Functional lesions were diagnosed in 6 (15.8%) of 38 that had functional work-up (diagnoses: pheochromocytoma (n = 2), adrenocorticotropic hormone-dependent hypercortisolism (n = 2), hyperandrogenism (n = 1), hyperaldosteronism (n = 1)); surgery was indicated for 5 (83.3%; n = 12 nodules), 2 of whom had bilateral, diffuse adrenal enlargement. Two patients were diagnosed with adrenocortical carcinoma and two with neoplasms of uncertain malignant potential. Radiographic or clinical progression of ALs is uncommon. Malignancy should be suspected on the basis of a lesion's growth rate and size. A baseline hormonal work-up is recommended, and no further biochemical work-up is suggested when the initial assessment shows nonfunctioning lesions.

Clinical and molecular features of four Brazilian families with multiple endocrine neoplasia type 1

Objective

Multiple endocrine neoplasia type 1 (MEN1) is an autosomal dominant syndrome characterized by its clinical variability and complexity in diagnosis and treatment. We performed both clinical and molecular descriptions of four families with MEN1 in a follow-up at a tertiary center in Brasília.

Methods

From a preliminary review of approximately 500 medical records of patients with pituitary neuroendocrine tumor (PitNET) from the database of the Neuroendocrinology Outpatient Clinic of the University Hospital of Brasília, a total of 135 patients met the criteria of at least two affected family members. From this cohort, we have identified 34 families: only four with a phenotype of MEN1 and the other 30 families with the phenotype of familial isolated pituitary adenoma (FIPA). Eleven patients with a clinical diagnosis of MEN1 from these four families were selected.

Results

Variants in MEN1 gene were identified in all families. One individual from each family underwent genetic testing using targeted high-throughput sequencing (HTS). All patients had primary hyperparathyroidism (PHPT), and the second most common manifestation was PitNET. One individual had well-differentiated liposarcoma, which has been previously reported in a single case of MEN1. Three variants previously described in the database and a novel variant in exon 2 have been found.

Conclusions

The study allowed the genotypic and phenotypic characterization of families with MEN1 in a follow-up at a tertiary center in Brasília.

Overview of the 2022 WHO Classification of Adrenal Cortical Tumors

The new WHO classification of adrenal cortical proliferations reflects translational advances in the fields of endocrine pathology, oncology and molecular biology. By adopting a question-answer framework, this review highlights advances in knowledge of histological features, ancillary studies, and associated genetic findings that increase the understanding of the adrenal cortex pathologies that are now reflected in the 2022 WHO classification. The pathological correlates of adrenal cortical proliferations include diffuse adrenal cortical hyperplasia, adrenal cortical nodular disease, adrenal cortical adenomas and adrenal cortical carcinomas. Understanding germline susceptibility and the clonal-neoplastic nature of individual adrenal cortical nodules in primary bilateral macronodular adrenal cortical disease, and recognition of the clonal-neoplastic nature of incidentally discovered non-functional subcentimeter benign adrenal cortical nodules has led to redefining the spectrum of adrenal cortical nodular disease. As a consequence, the most significant nomenclature change in the field of adrenal cortical pathology involves the refined classification of adrenal cortical nodular disease which now includes (a) sporadic nodular adrenocortical disease, (b) bilateral micronodular adrenal cortical disease, and (c) bilateral macronodular adrenal cortical disease (formerly known primary bilateral macronodular adrenal cortical hyperplasia). This group of clinicopathological entities are reflected in functional adrenal cortical pathologies. Aldosterone producing cortical lesions can be unifocal or multifocal, and may be bilateral with no imaging-detected nodule(s). Furthermore, not all grossly or radiologically identified adrenal cortical lesions may be the source of aldosterone excess. For this reason, the new WHO classification endorses the nomenclature of the HISTALDO classification which uses CYP11B2 immunohistochemistry to identify functional sites of aldosterone production to help predict the risk of bilateral disease in primary aldosteronism. Adrenal cortical carcinomas are subtyped based on their morphological features to include conventional, oncocytic, myxoid, and sarcomatoid subtypes. Although the classic histopathologic criteria for diagnosing adrenal cortical carcinomas have not changed, the 2022 WHO classification underscores the diagnostic and prognostic impact of angioinvasion (vascular invasion) in these tumors. Microscopic angioinvasion is defined as tumor cells invading through a vessel wall and forming a thrombus/fibrin-tumor complex or intravascular tumor cells admixed with platelet thrombus/fibrin. In addition to well-established Weiss and modified Weiss scoring systems, the new WHO classification also expands on the use of other multiparameter diagnostic algorithms (reticulin algorithm, Lin-Weiss-Bisceglia system, and Helsinki scoring system) to assist the workup of adrenal cortical neoplasms in adults. Accordingly, conventional carcinomas can be assessed using all multiparameter diagnostic schemes, whereas oncocytic neoplasms can be assessed using the Lin-Weiss-Bisceglia system, reticulin algorithm and Helsinki scoring system. Pediatric adrenal cortical neoplasms are assessed using the Wieneke system. Most adult adrenal cortical carcinomas show > 5 mitoses per 10 mm² and > 5% Ki67. The 2022 WHO classification places an emphasis on an accurate assessment of tumor proliferation rate using both the mitotic count (mitoses per 10 mm²) and Ki67 labeling index which play an essential role in the dynamic risk stratification of affected patients. Low grade carcinomas have mitotic rate of ≤ 20 mitoses per 10 mm², whereas high-grade carcinomas show > 20 mitoses per 10 mm². Ki67-based tumor grading has not been endorsed in the new WHO classification, since the proliferation indices are continuous variables rather than being static thresholds in tumor biology. This new WHO classification emphasizes the role of diagnostic and predictive biomarkers in the workup of adrenal cortical neoplasms. Confirmation of the adrenal cortical origin of a tumor remains a critical requirement when dealing with non-functional lesions in the adrenal gland which may be mistaken for a primary adrenal cortical neoplasm. While SF1 is the most reliable biomarker in the confirmation of adrenal cortical origin, paranuclear IGF2 expression is a useful biomarker in the distinction of malignancy in adrenal cortical neoplasms. In addition to adrenal myelolipoma, the new classification of adrenal cortical tumors has introduced new sections including adrenal ectopia, based on the potential role of such ectopic tissue as a possible source of neoplastic proliferations as well as a potential mimicker of metastatic disease. Adrenal cysts are also discussed in the new classification as they may simulate primary cystic adrenal neoplasms or even adrenal cortical carcinomas in the setting of an adrenal pseudocyst.

A MEN1 Patient Presenting With Multiple Parathyroid Adenomas and Transient Hypercortisolism: A Case Report and Literature Review

BACKGROUND

Multiple endocrine neoplasia type 1 (MEN1) is a hereditary endocrine syndrome caused by mutations in MEN1 tumor suppressor gene.

CASE PRESENTATION

A 53-year-old Chinese female was admitted to Division of Endocrinology, Tongji Hospital, for hypercalcemic crisis. Increased level of parathyroid hormone (PTH) was confirmed by laboratory tests, and imaging examination showed multiple parathyroid adenomas. Based on gene analysis, the patient was diagnosed as MEN1 associated hyperparathyroidism (HPT) by gene analysis with c.1378C>T (p.Arg460Ter) mutation in MEN1 gene. Her condition was complicated by transient hypercortisolism, mammary mass and uterine leiomyoma. After subtotal parathyroidectomy, PTH and serum calcium levels returned to normal.

CONCLUSION

HPT with multiple parathyroid adenomas is an indication of MEN1 gene mutation. Serum cortisol and its circadian rhythm can be abnormal in the presence of hypercalcemia and high PTH. These parameters can return to normal after parathyroidectomy.

A novel nonsense mutation in ARMC5 causes primary bilateral macronodular adrenocortical hyperplasia

BACKGROUND

Primary bilateral macronodular adrenocortical hyperplasia (PBMAH) is a rare form of adrenal Cushing's syndrome. The slowly progressing expansion of bilateral adrenal tissues usually persists for dozens of years, leading to delayed onset with severe conditions due to chronic mild hypercortisolism. About 20-50% cases were found to be caused by inactivating mutation of armadillo repeat-containing protein 5 (ARMC5) gene.

CASE PRESENTATION

A 51-year-old man was admitted for severe diabetes mellitus, resistant hypertension, centripedal obesity and edema. PBMAH was diagnosed after determination of adrenocorticotropic hormone and cortisol levels, dexamethasone suppression tests and abdominal contrast-enhanced CT scanning. The metabolic disorders of the patient remarkably improved after sequentially bilateral laparoscopic adrenalectomy combined with hormone replacement. Sanger sequencing showed germline nonsense mutation of ARMC5 c.967C>T (p.Gln323Ter). The second somatic missense mutation of ARMC5 was detected in one out of two resected nodules, reflecting the second-hit model of tumorigenesis. Routine genetic testing in his apparently healthy offspring showed one of two daughters and one son harbored the germline mutation.

CONCLUSIONS

In conclusion, our case report highlight the importance of genetic testing in the molecular diagnosis of PBMAH. Genetic screening in related family members will find out asymptomatic variant carriers to guide life-long follow-up.