Picture of the month. Multiple endocrine neoplasia 2B syndrome

Painful Hip Leading to the Diagnosis of MEN 2B Syndrome

Context. MEN 2B syndrome is characterized by the presence of medullary thyroid cancer, pheochromocytoma, mucosal neuromas, marfanoid features, and skeletal abnormalities like kyphoscoliosis, joint laxity, pes cavus, and slipped capital femoral epiphysis (SCFE) in a minority; we present the case of a young female who was brought to medical attention due to painful hip because of SCFE. Case Report. A 16-year-old female presented to orthopedics out-patient department (OPD) with complaints of pain around the left hip and walking with a limp for the last two months. MRI of hip confirmed the presence of SCFE of the left hip. General examination detected thyroid swelling which was found to be a medullary thyroid cancer and imaging of abdomen confirmed the presence of bilateral pheochromocytoma, also present were neuromas of tongue and lips. Thus, a diagnosis of MEN 2B syndrome was made. Conclusion. SCFE can sometimes be the presenting feature of MEN 2B syndrome. Physicians should keep this in mind as it can lead to early diagnosis of a potentially lethal illness.

Multiple Endocrine Neoplasia Type 2B: Early Diagnosis by Multiple Mucosal Neuroma and Its DNA Analysis

Multiple endocrine neoplasia type 2B (MEN 2B) is a rare disease caused by germline mutations in the RET proto-oncogene and is transmitted in an autosomal dominant fashion. It is characterized by medullary thyroid carcinoma, pheochromocytoma and mucosal neuroma developing in the tongue, lip, intestinal tract, palate etc. Among these neoplasias, mucosal neuroma generally develops from early childhood. Therefore, early detection and proper treatment can minimize the disease course. Here we describe a 9-year-old male who presented with multiple verrucous papules and nodules on his lips, tongue and gingiva that were there since birth. Histologic findings of his lips and tongue showed well-defined nerve bundles and DNA analysis revealed a M918T mutation at codon 918 of the RET oncogene. He was diagnosed early as having MEN 2B according to his genetic and phenotypic features.

Early diagnosis of multiple endocrine neoplasia type 2B: a challenge for physicians

BACKGROUND

The hereditary form of medullary thyroid carcinoma may occur isolated as a familial medullary thyroid carcinoma (FMTC) or as part of Multiple Endocrine Neoplasia 2A (MEN2A) and 2B (MEN2B). MEN2B is a rare syndrome, its phenotype may usually, but not always, be noted by the physician. In the infant none of the MEN2B characteristics are present, except by early gastrointestinal dysfunction caused by intestinal neuromas. When available, genetic analysis confirms the diagnosis and guides pre-operative evaluation and extent of surgery. Here we report four cases of MEN2B in which the late diagnosis had a significant impact in clinical evolution and, potentially, in overall survival.

CASE REPORT

We report four cases, 2 men and 2 women, with differences in their phenotypes and with a late diagnosis. The first case has a history of severe gastrointestinal obstruction requiring a surgery intervention two days after his birth. The second told had nodules in the oral mucosa and constipation since childhood. The third case referred a history of constipation from birth until 5 months of life. The fourth has had a history of chronic constipation since childhood.

DISCUSSION

New concepts have emerged since the RET oncogene was identified in 1993 as the responsible gene for hereditary medullary thyroid carcinoma. The majority of MEN2B individuals have M918T mutation in the exon 16 of RET, with a few cases having a mutation A883F or the association of V804M with E805K, Y806C or S904C mutations. The consensus classifies the RET mutation in codon 918 as of highest risk and recommends total thyroidectomy and central lymph node dissection until 6 months after birth. A fast and precise diagnosis is essential to reach these goals. The identification of early manifestations such as intestinal ganglioneuromatosis and oral mucosal neuromas should prompt the physician to initiate an investigation for multiple endocrine neoplasia type 2B.

CONCLUSION

The diagnosis of MEN2B is very important to allow appropriate investigation of associated diseases and to allow counseling and appropriate screening of relatives for a RET mutation. Even patients with MEN2B, which often have typical physical features, may not be properly recognized and be followed as a sporadic case. Based on this, all suspicious cases of multiple endocrine neoplasia should undergo a molecular genetic test.

Oral manifestations of systemic disease

Most systemic diseases can affect the oral cavity. Some oral changes are nonspecific, whereas others directly lead to the diagnosis of a particular disorder. A systems approach is used here to catalog these oral changes. In some instances it is difficult to separate the oral manifestations of pharmacotherapy for a particular disease from that entity. The oral manifestations of pharmacotherapy are presented for selected disease processes. This article introduces the most common oral manifestations of systemic disease.