Endocrine Abstracts

Neuroendocrine neoplasias (NENs) are a heterogeneous group of tumors that differ in appearance, growth patterns, and clinical symptoms and develop from neuroendocrine cells and, accordingly, unusually similar cytological characteristics. Pheochromocytoma is considered as not epithelial type of NENs. We would like to present a clinical case of pheochromocytoma with difficulties in laboratory diagnosis and morphological verification. Female patient P., 60 years old, for 10 years, she was observed by a cardiologist with arterial hypertension (Grade 3) and chronic heart failure (NYHA Clase III), antihypertensive therapy with 3 standard preparations has been repeatedly adjusted without sufficient clinical response. On treatment, patient had blood pressure up to 200/100 mm Hg accompanied by sweating, episodes of flushes of heat to the face. CT of the abdominal organs incidentally detected a left adrenal tumor size 46×41×45 mm (native density +14+52 HU). Daily urine: normetanephrine 471 mg/day (30–440), metanephrine 60 mg/day (30–440); chromogranin A 23.6 nmol/l (0.54–3). Laparoscopic left adrenalectomy was performed. According to the histological examination of the adrenal tumor, predominantly formed from the structure of a solid and alveolar with the presence of an angiomatous component of large cystic dilated vessels, from small monomorphic tumors cells with a narrow cytoplasm and a rounded nucleus, which in structure most of all resemble the structure of neuroendocrine tumors of the small intestine, "typical carcinoids". The minor component of the structure, characteristic of "classical" pheochromocytomas, was formed from alveolar structures from larger cells with abundant light cytoplasm, with nuclear and cellular polymorphism. When a tumor is detected, invasion of vessels into the tumor and local invasion of capsules. Considering the fact that the tumor has a non-specific structure for pheochromocytes, differential diagnosis was carried out between pheochromocytoma and metastases of intestinal NET or other localizations. Immunohistochemical detection of chromogranin A expression foci, a higher density in areas of a “typical” pheochromocytoma, as well as synaptophysin and CD56, revealed focal uneven expression of vimentin, as well as focal serotonin expression mainly in areas of a “carcinoid structure”. There is no expression of pan-cytokeratin, TFF-1, CDX-2. The average Ki67 2-8% (max 11%).

Conclusion: Pheochromocytoma of the adrenal gland "carcinoid-like" structure. After operation, the patient noted the normalization of blood pressure without preparations. This clinical case demonstrates the diversity of the clinical course and histological picture. Based on this, to establish an accurate diagnosis, we need detailed approach with a mandatory Immunohistochemical study to determine further tactics of treatment and monitoring.