Clinical and immunohistochemical characteristics of pheochromocytomas

BACKGROUND. Currently, pheochromocytomas are classified as malignant tumors (WHO 2017), which means that special postoperative tactics are required for patients with different risks of pheochromocytoma aggressiveness.AIM. Assess the predictors of malignant potential of pheochromocytomas using the GAPP and PASS scales.MATERIALS AND METHODS. From 2016 to 2021, 24 patients diagnosed with pheochromocytoma, age from 18 to 81 years (median 50.4+-3.3), were hospitalized at the Primorsky Regional Center for Diabetes and Endocrine Diseases, 21 of them were women and 3 were men. Hormone producing adenoma in the right adrenal gland was found in 13 patients (54.2%), on the left in 8 (33.3%) cases, bilateral pheochromocytoma — in 3 (12.5%) cases. Clinical manifestation: a sharp increase in systolic blood pressure of more than 200 mmHg accompanied by crises, tachycardia was detected in 14 patients, the rest of the clinical symptoms were nonspecific: persistent arterial hypertension, as well as general weakness. The sizes of the revealed formations varied from — 1.1x1.6x1.6 cm to — 7.7x10.6x8.5 cm. (median 37+-1.2). The diagnosis was confirmed by standard examinations. All patients underwent unilateral adrenalectomy at the Surgery Center of the FEFU Medical Center, using two main methods: retroperitoneoscopy and laparoscopy. After the operation, histological and immunohistochemical studies were performed. The analysis of immunohistochemical studies was carried out. The expression of Ki67, Chromogranin A, Synaptophysin was determined. Since it is currently impossible to absolutely accurately determine the malignant potential of pheochromocytomas, the PASS and GAPP scores have been introduced into clinical practice. A retrospective analysis of the cytological material of patients operated on in 2020 and 2021 was carried out.RESULTS. According to the PASS scale, more than 4 points were detected in 7 out of 10 patients. GAPP scores ranged from 0 to 2 in 3 out of 10 people; 3-6 points for 5; more than 7 points in 2 patients. At the same time, the results of the calculation on both scales in 100% of cases correspond to each other, which makes it possible to identify patients with moderate and high malignant potential.CONCLUSION. The results obtained confirm the need to use additional tools in clinical practice to determine the prognosis in a particular patient, which means it will allow developing an algorithm for dispensary observation, the timing of the follow-up examination.