Multiple endocrine neoplasia type 2B with hyperparathyroidism: A case report and literature review

Abstract MEN2B is characterized by medullary thyroid carcinoma (MTC), pheochromocytoma (PHEO) and without hyperparathyroidism, over 95% of which patients have mutations in codon M918T (at exon 16). Early diagnosis of MEN2B has important implications for the treatment and prognosis of the disease, as thyroidectomy has the potential to cure patients. In this case, the patient was a 31-year-old man presented with low back pain as the initial and primary symptom. In addition to MTC and PHEO, the examination showed that he also had hyperparathyroidism, which led to the misjudgment of MEN typing at first. We finally diagnosed this patient as MEN2B based on the results of genetic testing. After the operation and treatment, the patient recovered well. Early diagnosis is the key to the MEN2B treatment. Whether MEN2A and MEN2B can be distinguished by the presence of parathyroidism still needs more researches to verify. RET gene detection plays an important role in the diagnosis and prognosis of MEN2B and surgery is the first choice for the treatment of MEN2B.