Recurrent Pheochromocytoma, as Component of Multiple Endocrine Neoplasia

Background: Pheochromocytoma is a rare neuroendocrine tumor from the adrenal medulla’s chromaffin cells that secrete catecholamines. The mainstay of treatment is surgery. Although rare, it has a recurrence rate of 6.5-16.5% even after adequate surgical removal with a notable increase in prevalence among genetic syndromes, extra-adrenal tumors, larger tumor size, and younger age of diagnosis. Case: A 23-year-old Filipino male with no known familial disease presented with episodic headache, palpitations, diaphoresis, and resistant hypertension. Two masses in the left adrenal gland, with the larger one measuring 6.0cm x 5.0cm x 3.0cm, were surgically removed. Histologic examination revealed pheochromocytoma. Post-operatively, there was the normalization of urinary metanephrines and the resolution of the signs and symptoms. He was lost to follow-up and returned five years later with an abdominal ultrasound demonstrating a right adrenal mass. He had no accompanying signs and symptoms; the physical examination was unremarkable. On workup, biochemical testing revealed two 24-hour urinary metanephrine levels were markedly elevated, 14.49 and 19.97 (NV:0-1mg/24 hours). Calcitonin: 644 (NV:0-18pg/ml) and carcinoembryonic antigen (CEA): 23.52 (NV:<5ng/ml) were also elevated. Mild hypercalcemia was noted with elevated intact PTH 101.74 (NV:0-65pg/ml). Parathyroid scintigraphy was normal. The neck ultrasound showed multiple bilateral thyroid nodules, with the largest measuring 1.2cmx0.9cm (TIRADS IV). The abdominal CT scan showed two well-defined, homogenous right adrenal masses, with the largest measuring 6.3cm x 5.6cm x 7.4cm. He underwent right adrenalectomy, and histopathology showed pheochromocytoma with Pheochromocytoma of the Adrenal Scale Score (PASS) of 3. One month later, he underwent total thyroidectomy with neck dissection and inferior parathyroid gland resection. Histopathology confirmed medullary thyroid cancer with nodal metastasis and parathyroid adenoma. The patient recovered well without complications. Biochemical tests normalized eight weeks post-surgery. The presence of synchronous recurrent pheochromocytoma, medullary thyroid cancer (MTC), and primary hyperparathyroidism is consistent with multiple endocrine neoplasia 2A (MEN2A) syndrome. Conclusion: Lifelong follow-up is essential in patients treated for pheochromocytoma despite the complete removal of the adrenal masses due to recurrence risk. Recurrence should likewise raise the suspicion of MEN2, a genetic syndrome. In addition, the pheochromocytoma has malignant characteristics, and the MTC has metastases to the cervical lymph nodes. Early detection and prompt intervention are essential for the treatment of the disease.