Endocrine Abstracts

Background: Pheochromocytomas and paragangliomas (PPGLs) are rare neuroendocrine tumors characterized by a high degree of variability and unpredictability. Coexistence of PPGLs and adrenocortical adenomas is an uncommon occurrence that can further complicate the clinical course.

Objective: We describe the diagnostic and management challenges of a patient with a history of surgically removed pheochromocytoma, presenting with symptoms of catecholamine excess, following a prolonged period of clinical remission.

Case Report: A 52 yo. female patient was admitted to our hospital for surgical cure of a left adrenal mass. She reports a history of right adrenal pheochromocytoma, excised 15 years before and resulting in clinical and biochemical remission. 15 months prior to presentation she started experiencing paroxysms of arterial hypertension, occurring every other day, accompanied by headache, palpitations, tremor, nausea and emesis. Abdominal CT showed a 3/2 cm left adrenal adenoma, while biochemical screening revealed elevated plasma normetanephrines (6x upper normal limit), along with normal metanephrines and chromogranin A. Renin-to-aldosterone ratio and cortisol diurnal variation were unaltered, but ACTH values were slightly decreased. Postoperatively, the patient was initially stable and exhibited normalized blood pressure under high-dose corticoid treatment, but on the 3^rd day, as corticoid dosage was decreased, she developed an acute adrenal crisis. In spite of the initial suspicion of adrenal pheochromocytoma, histopathological and immunohistochemical examinations described an adrenocortical adenoma. Unsurprisingly, normetanephrines failed to normalize postoperatively; metanephrines and chromogranin A also became marginally elevated and symptoms reoccurred. MRI examination of the head and neck was negative. Interestingly, the patient now also described lumbosacral warmth accompanying the paroxysms. Octreoscan was performed, but revealed no areas of high uptake. Conversely, a metabolically active sacral lesion was described on PET-CT. MRI confirmed the presence of an osteolytic lesion (1.8/1.4/1.1 cm) in that area and described an additional similar adjacent lesion. These were interpreted as possible metastases of a malignant PPGL. Neurosurgical intervention was performed and a histopathological diagnosis of grade I WHO paraganglioma was established. The patient exhibited clinical remission postoperatively, along with the decline of all tumoral markers. However, 6 months later, in spite of imagistic regression of the sacral lesions and lack of symptoms, both metanephrines and normetanephrines showed an upward tendency.

Conclusion: Long-term follow-up is mandatory in PPGLs, as clinical recurrence is possible even after prolonged periods of remission. Genetic testing can aid the diagnosis and management and should be ideally performed in all cases of recurrent/aggressive PPGLs.