Multiple endocrine neoplasia type 2: clinical manifestations and management

Multiple endocrine neoplasia type 2: A reveiw

Multiple endocrine neoplasias are rare hereditary syndromes some of them with malignant potential. Multiple endocrine neoplasia type 2 (MEN 2) is an autosomal dominant hereditary cancer syndrome due to germline variants in the REarranged during Transfection (RET) proto-oncogene. There are two distinct clinical entities: MEN 2A and MEN 2B. MEN 2A is associated with medullary thyroid carcinoma (MTC), phaeochromocytoma, primary hyperparathyroidism, cutaneous lichen amyloidosis and Hirschprung's disease and MEN 2B with MTC, phaeochromocytoma, ganglioneuromatosis of the aerodigestive tract, musculoskeletal and ophthalmologic abnormalities. Germline RET variants causing MEN 2 result in gain-of-function; since the discovery of the genetic variants a thorough search for genotype-phenotype associations began in order to understand the high variability both between families and within family members. These studies have successfully led to improved risk classification of prognosis in relation to the genotype, thus improving the management of the patients by thorough genetic counseling. The present review summarizes the recent developments in the knowledge of these hereditary syndromes as well as the impact on clinical management, including genetic counseling, of both individual patients and families. It furthermore points to future directions of research for better clarification of timing of treatments of the various manifestations of the syndromes in order to improve survival and morbidity in these patients.

3P's of Wermer/MEN1 Syndrome on 68Ga-DOTANOC PET/CT Scan

Wermer/MEN1 syndrome is composed of the triad of pancreatic, pituitary, and parathyroid (3P's) tumors. We describe the Ga-DOTANOC PET/CT findings of a 43-year-old man, which revealed the classic 3P's of MEN1 syndrome with somatostatin receptor expression. The patient further underwent surgery for parathyroid lesions, which were suggestive of adenomas.

Primary hyperparathyroidism as first manifestation in multiple endocrine neoplasia type 2A: an international multicenter study

OBJECTIVE

Multiple endocrine neoplasia type 2A (MEN 2A) is a rare syndrome caused by RET germline mutations and has been associated with primary hyperparathyroidism (PHPT) in up to 30% of cases. Recommendations on RET screening in patients with apparently sporadic PHPT are unclear. We aimed to estimate the prevalence of cases presenting with PHPT as first manifestation among MEN 2A index cases and to characterize the former cases.

DESIGN AND METHODS

An international retrospective multicenter study of 1085 MEN 2A index cases. Experts from MEN 2 centers all over the world were invited to participate. A total of 19 centers in 17 different countries provided registry data of index cases followed from 1974 to 2017.

RESULTS

Ten cases presented with PHPT as their first manifestation of MEN 2A, yielding a prevalence of 0.9% (95% CI: 0.4-1.6). 9/10 cases were diagnosed with medullary thyroid carcinoma (MTC) in relation to parathyroid surgery and 1/10 was diagnosed 15 years after parathyroid surgery. 7/9 cases with full TNM data were node-positive at MTC diagnosis.

CONCLUSIONS

Our data suggest that the prevalence of MEN 2A index cases that present with PHPT as their first manifestation is very low. The majority of index cases presenting with PHPT as first manifestation have synchronous MTC and are often node-positive. Thus, our observations suggest that not performing RET mutation analysis in patients with apparently sporadic PHPT would result in an extremely low false-negative rate, if no other MEN 2A component, specifically MTC, are found during work-up or resection of PHPT.

Overview of Genetically Determined Diseases/Multiple Endocrine Neoplasia Syndromes Predisposing to Endocrine Tumors

In this chapter, we present an overview of multiple endocrine neoplasia syndromes including their most important clinical and molecular features. Multiple endocrine neoplasia type 1 and 2 syndromes (MEN1 and MEN2) are discussed in detail. Syndromes that are presented in other chapters are only briefly mentioned. We discuss the relevance of germline gene alterations in apparently sporadic endocrine tumors, e.g., medullary thyroid cancer, primary hyperparathyroidism, and neuroendocrine tumors. McCune-Albright syndrome that only exists in non-hereditary, sporadic forms is also discussed in detail, as tumors of several endocrine organs can develop in the same individual.

Quality of life in multiple endocrine neoplasia type 2A compared with normative and disease populations

BACKGROUND

Patient-reported outcomes are measured in chronic disease states to inform intervention and management decisions while minimizing negative outcomes. We hypothesized that health-related quality of life in patients with multiple endocrine neoplasia type 2A would be worse than the general US population but similar to other chronic diseases.

METHODS

Adults ≥18 years with multiple endocrine neoplasia type 2A were recruited to complete the Patient-Reported Outcomes Measurement Information System 29-item questionnaire (n = 45). Scores based on the Patient-Reported Outcomes Measurement Information System T-score metric were compared with the general US population and with cohorts with low back pain, cancer, congestive heart failure, chronic obstructive pulmonary disease, major depressive disorder, rheumatoid arthritis, neuroendocrine tumors, primary hyperparathyroidism, and MEN1.

RESULTS

Compared with US normative data, multiple endocrine neoplasia type 2A patients reported worse anxiety (58.2 ± 12.0, P < .0001), depression (55.4 ± 12.0, P < .01), fatigue (61.4 ± 10.8, P < .0001), pain interference (54.0 ± 11.5, P < .05), and sleep disturbance (56.9 ± 2.7, P < .001), as well as significantly lower physical functioning (45.7 ± 9.3, P < .01) and ability to participate in social roles (46.4 ± 9.7, P < .05). Multiple endocrine neoplasia type 2A patients reported greater fatigue than patients with cancer (P < .0001), chronic obstructive pulmonary disease (P = .01), rheumatoid arthritis (P = .0002), neuroendocrine tumors (P = .0007), and primary hyperparathyroidism (P < .0001) but higher physical functioning compared with patients with rheumatoid arthritis (P = .02), low back pain, congestive heart failure, and chronic obstructive pulmonary disease (P < .0001).

CONCLUSIONS

This study is the first to use the Patient-Reported Outcomes Measurement Information System to compare patient-reported outcomes between multiple endocrine neoplasia type 2A and other chronic conditions. Individuals with multiple endocrine neoplasia type 2A reported worse health-related quality of life in all 7 domains compared with US normative data. Multiple endocrine neoplasia type 2A patients reported greater fatigue but greater physical function compared with several other conditions. Prospective longitudinal evaluation of patient-reported outcomes in multiple endocrine neoplasia type 2A should be conducted to identify treatments associated with the highest health-related quality of life.

Multiple Endocrine Neoplasia Type 2B Unmasked by 18 F-FDG PET/CT and 131 I-MIBG SPECT/CT

F-FDG PET/CT was performed to detect an occult malignancy in a 26-year-old woman with complicated medical history which included paroxysmal hypertension and significantly elevated tumor marker. The images revealed lesions in the thyroid, lymph nodes, and bilateral adrenal glands. Further I-MIBG SPECT/CT revealed intense activity in the lesion in the left adrenal gland, which was consistent with pheochromocytoma. The pathology examination after subsequent neck biopsy demonstrated medullary thyroid carcinoma. A diagnosis of multiple endocrine neoplasia type 2B was eventually made.

Accuracy of 68Ga DOTANOC PET/CT Imaging in Patients With Multiple Endocrine Neoplasia Syndromes

OBJECTIVE

The aim of this study was to evaluate the role of ⁶⁸Ga DOTANOC PET/CT imaging in patients with multiple endocrine neoplasia (MEN) syndromes.

PATIENTS AND METHODS

Data of 33 patients (age, 33.5 [13.8] years; male 14/female 19) with MEN syndromes (MEN 1, 9; MEN 2A, 19; MEN 2B, 5) who underwent 41 ⁶⁸Ga DOTANOC PET/CT studies were retrospectively analyzed. Twenty PET/CTs were done for staging and 21 for restating. PET/CT images were evaluated in consensus by 2 nuclear medicine physicians, qualitatively and semiquantitatively (SUV(max)). A combination of histopathology, clinical, and biomarker follow-up was taken as reference standard.

RESULTS

Of the total 41 ⁶⁸Ga DOTANOC PET/CTs, 34 were interpreted as positive for neuroendocrine tumors (NETs) and 7 as negative. The patientwise sensitivity of PET/CT was 94% (95% confidence interval [CI], 80-99), specificity was 71% (95% CI, 29-96), positive predictive value was 94% (95% CI, 80-99), negative predictive value was 71% (95% CI, 29-96), and accuracy was 90%. A total of 74 disease sites were demonstrated on PET/CT, including 41 primary NETs (pancreas, 10; stomach, 2; pheochromocytoma, 10; medullary thyroid carcinoma, 19), 31 metastatic sites (lymph node, 15; liver, 10; bone, 4; lung, 1; breast, 1), and 2 parathyroid adenomas. Lesionwise sensitivity, positive predictive value, and accuracy of PET/CT were 93%, 96%, and 90% overall, 89%, 95%, and 85% for primary tumors, and 100%, 97%, and 97% for metastasis, respectively. Among primary tumors, the SUV(max) of medullary thyroid carcinoma was significantly lower than gastro pancreatic NETs (P = 0.003) and pheochromocytomas (P = 0.003). No site-specific difference was seen in SUV(max) of metastatic lesions.

CONCLUSIONS

⁶⁸Ga DOTANOC PET/CT shows high diagnostic accuracy in MEN syndrome and can demonstrate both primary and metastatic NETs in these patients.

Pheochromocytoma in an 8-year-old patient with multiple endocrine neoplasia type 2A: implications for screening

Childhood pheochromocytoma in the setting of multiple endocrine neoplasia type 2 (MEN2) remains rare and has not been reported under the age of 12. We present an 8-year-old female with known MEN 2A, C634Y RET mutation, diagnosed with a 6 cm pheochromocytoma requiring laparoscopic adrenalectomy. Given this patient's age at diagnosis, screening guidelines should recommend annual screening beginning at age 8 for patients with MEN 2B or MEN 2A codons 630 or 634 RET mutations.

Integrated DNA-based/biochemical screening for early diagnosis of multiple endocrine neoplasia type 2A (MEN2A)

Multiple endocrine neoplasia type 2A (MEN2A), a subtype of MEN2, is characterized by medullary thyroid cancer, pheochromocytoma, and primary hyperparathyroidism. A Han Chinese pedigree with MEN2A was investigated following confirmation of the proband's diagnosis by pathological findings and DNA/biochemical screening. DNA samples from 4 other family members were collected and exon 5, 8, 10, 11, 13, 16 and 18 of the RET proto-oncogene were sequenced and then analyzed. A missense mutation of TGG (Trp) to TGC (Cys) at codon 634 (the classic MEN2A mutation) in exon 11 of the RET gene was detected in 3 family members, including the proband. Sequencing data were compared with the human gene mutation database. Elevated serum calcitonin level was detected initially; medullary thyroid carcinoma was revealed in the 3 cases and adrenal pheochromocytoma was also found in the proband. Elective operations were successfully performed on the adrenal and thyroid glands because of pheochromocytoma and medullary thyroid carcinoma. Our case study confirms that integrated DNA-based/biochemical screening is crucial for early diagnosis of MEN2A and is helpful in the screening of their relatives. In addition, DNA-based screening may occasionally uncover a previously unknown RET sequence.

Multiple endocrine neoplasia type 2A

Multiple endocrine neoplasia type 2A (MEN 2A) is an autosomal dominant inherited cancer syndrome that expresses nonendocrine and endocrine tumors. Here, we describe a 42-year-old man with an initial presentation of low back pain and hypertension. Clinical assessments revealed pheochromocytoma, medullary thyroid carcinoma with bone metastasis, and parathyroid hyperplasia. MEN 2A was diagnosed, and a family history of pheochromocytoma was traced. Surgical resection of the pheochromocytoma of the adrenal gland resulted in a cure of the patient's hypertension. He received systemic chemotherapy with the "MAID" regimen (mesna, doxorubicin, ifosfamide, and dacarbazine) over three cycles of 3 weeks each, and showed a partial response.

The genetic counselor: an important surgical ally in the optimal care of the cancer patient

Genetic counselors and surgeons both have important roles in the care of patients with hereditary cancer predisposition syndromes. Surgeons have the initial responsibility to identify and refer high-risk patients. Genetic counselors' specialized skill sets are then used in the risk assessment and genetic evaluation of such patients and their at-risk family members, and this may be performed in multiple settings. As discussed in this article, these roles and the processes of genetic counseling and genetic testing may be enhanced through multiple surgeon and genetic counselor collaborations. Continued medical management of patients and families with hereditary cancer predisposition syndromes becomes the responsibility of patients and their multiple health care providers. Box 7 provides a list of resources to assist in finding a local genetic counselor. Because there are various opportunities for surgeons and genetic counselors to collaborate, the authors urge surgeons to recognize the importance of, identify, and work in partnership with a local genetic counselor because that relationship sets the stage for optimal care of the cancer patient.