A recent study published in Diagnostics reported that surveillance, careful review of the family history, pathology, and genetic counseling are the critical factors for a successful diagnosis of multiple endocrine neoplasia type 2A (MEN2A).

The study analyzed the case of a 49-year-old male patient diagnosed with MEN2A syndrome and adrenal pheochromocytoma (PHEO) at 31 years of age. His elder sister was diagnosed with left adrenal PHEO and right thyroid follicular carcinoma at 28 years of age and left thyroid medullary thyroid carcinoma (MTC) at 45 years of age.

Read more about medullary thyroid cancer therapies

She was misdiagnosed earlier due to limited medical records. The patient’s father also had surgeries for PHEO and MTC at 42 years of age, and he used to have intermittent hypertension, dizziness, cardiac palpitation, epileptic seizure, etc.

Multiple Endocrine Neoplasia 2A is an autosomal dominant inherited disorder that affects the endocrine system. It is caused by germline mutations in the RET proto-oncogene, leading to the development of tumors in the thyroid gland, adrenal medulla, and parathyroid glands. Due to its hereditary nature, screening for MEN2A mutations in at-risk families is of utmost importance for early detection and management.

“Because of the metachronous onset of the disease and lack of digital medical records in the past, the syndrome was not found until a recent fine needle aspiration of an MTC-metastasized lymph node from the son,” the authors highlighted.

Results revealed the wrong diagnosis of thyroid follicular carcinoma instead of MTC, suggesting that the patient’s elder sister had both MTC and PHEO in 17 years duration. Additionally, the misdiagnosis was not recognized earlier since her first medical record in the early 1990s was not digitalized and disconnected from her second record until it was manually discovered.

Furthermore, the MEN2A syndrome was missed because of the metachronous onset of the disease, which was misdiagnosed as thyroid adenoma or follicular carcinoma in the patient and her sister. These results suggested that high suspicion was a critical starting point in disease diagnosis. Moreover, a thorough review of past medical records and molecular screening was crucial to the right diagnosis.

Additional molecular analysis through targeted sequencing revealed a RET germline mutation in the family consisting of the three members with the disease onset and 1 granddaughter who didn’t show any symptoms during the testing period. Despite the familiar nature of this syndrome, it can still be misdiagnosed due to its rarity and long disease onset.


Chen L, Zhang JX, Liu DG, et al. Familial case of multiple endocrine neoplasia 2A: from morphology to genetic alterations penetration in three generations of a family. Diagnostics 2023. Published online March 2, 2023.