Incidental Detection of Synchronous Medullary Thyroid Carcinoma, Pheochromocytoma and Parathyroid Adenoma Leading to Diagnosis of Multiple Endocrine Neoplasia Type 2A

Introduction: Multiple endocrine neoplasia type 2 (MEN2) is an autosomal dominant neoplastic syndrome with an estimated prevalence of 1 per 30,000 in the general population. MEN2 is subclassified into two subtypes: 2A (MEN2A) and 2B (MEN2B). MEN2A is a rare disease and the affected patients are generally asymptomatic. Cutaneous lichen amyloidosis is an early clinical marker. The morbidity and mortality in these patients are mainly due to medullary thyroid carcinoma, therefore proper clinical workup is warranted for proper surgical intervention.
Case Description: We report a case of sporadic MEN2A with no family history of any thyroid or adrenal tumors. She presented with neck mass and complaints of sweating, breathlessness, tremors and impending doom. Contrast enhanced computed tomography revealed a well-defined smoothly marginated, heterogenous enhancing mass in left lobe of thyroid gland. The patient also had a maculopapular rash on upper back suggestive of cutaneous lichen amyloidosis. A finding of a solid necrotic mass in left suprarenal location of size 6x5x4.5 cm likely of left adrenal origin was also noted. The laboratory parameters including serum calcitonin, plasma metanephrines and parathyroid hormone levels were elevated. TC^99m Sestamibi scan revealed a left inferior parathyroid adenoma near lower pole of left thyroid lobe. She underwent left adrenalectomy and total thyroidectomy with central neck dissection one month apart. Histopathological examination confirmed the presence of synchronous medullary thyroid carcinoma (MTC), pheochromocytoma and parathyroid adenoma.
Conclusion: This case report highlights the importance of recognizing the clinical manifestations of MEN2A. Early diagnosis with proper and complete workup allows for timely and proper intervention and decrease the morbidity and mortality associated with MEN2A due to MTC.