Endocrine Abstracts

JOINT3530

Introduction: Composite pheochromocytoma (CP) is an exceptionally rare tumor (3% of the cases of pheochromocytomas) derived from neural crest cells. It is characterized by the coexistence of a chromaffin cell tumor and another tumor of neuronal origin, most commonly a ganglioneuroma, which arises from autonomic ganglion cells of the nervous system. The majority of diagnoses occur between the third and fifth decades.

Case Report: A 53-year-old woman, medicated with a combined oral contraceptive, presented with an incidental left adrenal mass identified on abdominal magnetic resonance imaging (MRI) performed for study of Hepatic focal nodular hyperplasia. Her family history was positive for melanoma (mother) and prostate cancer (father). The patient was referred to the endocrinology department for further investigation. She reported episodic palpitations and excessive sweating. Arterial hypertension was not observed. MRI demonstrated an expansive lesion at the left adrenal limb junction, measuring 28x24 mm, with necrotic areas and solid components, displaying T2 hyperintensity displayed, T1 hypointensity and progressive contrast uptake, particularly avid at the periphery during the arterial phase, suggestive of pheochromocytoma. Biochemical evaluation revealed elevated plasma metanephrines (163 pg/ml normal <90 pg/ml), elevated urinary total metanephrines (1154 µg/day; normal <320), including urinary metanephrines (646 µg/day; normal <320), urinary normetanephrines (392 µg/day; normal <390) and normal chromogranin (2.6 ng/mL, normal <100ng/mL). Staging with 123I-MIBG scintigraphy showed intense radiopharmaceutical uptake at the lesion site, with no evidence of distant lesions. The patient underwent laparoscopic left adrenalectomy with perioperative alpha-blockade (doxazosin), without complications. Histopathological analysis revealed a composite pheochromocytoma with ganglioneuroma, with complete surgical excision. Genetic testing did not identify any mutations associated with pheochromocytoma-related syndromes. The patient showed improvement in symptoms, with normalization of metanephrines 4 weeks after surgery.

Discussion/conclusion: CPs are rare entities requiring multidisciplinary management. Adrenalectomy is the gold standard treatment. There are cases of CPs with a malignant neurogenic component, however, CPs with ganglioneuroma component usually have an indolent behavior. Careful histopathological examination is essential. Genetic testing may provide insights into potential hereditary syndromes linked to composite adrenal tumors.