[Surgical treatment of pheochromocytoma].

This review article contains a summary of modern aspects of preoperative preparation, surgical treatment, and follow-up of patients with adrenal pheochromocytomas. The main component of preoperative preparation is the use of alpha-blockers. The need to prescribe them to all patients is increasingly disputed, especially for patients without severe hypertension. An increasing number of publications demonstrate positive results of treatment without the use of alpha-blockers, advocating an individual approach and the use of the drug according to certain indications. Minimally invasive endoscopic techniques of adrenalectomy have become widespread in surgical treatment. They are represented by laparoscopic and retroperitonescopic technic, including using their single-port modifications. The earliest possible intersection of the central vein in the past was considered the most important aspect of adrenalectomy for pheochromocytoma, currently, due to the development of surgical techniques and anesthesiological manuals, this has ceased to be a mandatory rule of successful surgery. Despite the significant influence of the intersection of this vessel on intraoperative hemodynamics, surgical tactics with its later intersection have their own justifications and do not lead to a deterioration in treatment results. The standard volume of surgical intervention for pheochromocytomas is total adrenalectomy, however, in the presence of hereditary syndromes, such as multiple endocrine neoplasia type 2 syndrome, neurofibomatosis type 1, von Hippel-Lindau syndrome, it is possible to perform cortical-sparing adrenalectomy.

[Corticotropin-producing pheochromocytoma in multiple endocrine neoplasia type 1].

A clinical case of a man 66 y.o. who was diagnosed with hormone-inactive pituitary macroadenoma complicated by corneal erosion and partial atrophy of the optic nerve of the left eye due to exophthalmos. The increase in prolactin level was regarded due to a «stalk-effect¼. The patient underwent a transnasal pituitary adenomectomy with subsequent regression of symptoms. After 4 years, against the background of a new coronavirus infection, increasing general weakness, headaches, a crisis increase in blood pressure and tachycardia attacks appeared. Computed tomography (CT) accidentally revealed an adrenal incidentaloma, in laboratory tests - hypercortisolism, elevated ACTH levels, hypokalemia, hyperglycemia, increased levels of metanephrine and normetanephrine. The patient developed acute steroid psychosis, after which an adrenalectomy with a tumor was performed, a pheochromocytoma was histologically confirmed. After surgery, there was a regression of symptoms, the development of adrenal insufficiency with reduced levels of ACTH and cortisol. Upon further examination, a polynodose euthyroid goiter was established, the biopsy of the nodes - Hashimoto's thyroiditis (Bethesda II). Meanwhile, primary hyperparathyroidism was detected. According to ultrasound, scintigraphy with Ts99m-Technetril and CT revealed an increase of left parathyroid gland. A bilateral revision of the neck, removal of the right upper and left upper parathyroid adenomas were performed. In the postoperative period, the levels of calcium and parathyroid hormone were normalized. Given the presence of a combination of multiple tumors of the endocrine system (primary hyperparathyroidism, corticotropin-producing pheochromocytoma, hormone-inactive pituitary macroadenoma, polynodose euthyroid goiter), the MEN1 syndrome was clinically established. The study of 2 and 10 exons of the MEN1 gene revealed no mutations, which does not exclude the presence of a hereditary syndrome. The patient continues observation. In the available literature in Russian and English languages the case of ACTH pheochromocytoma as part of the MEN type 1 syndrome have not been found. Therefore, we consider the presented case to be the first one.

[Metastatic risk factors in pheochromocytoma/paraganglioma].

Currently, all pheochromocytoma/paraganglioma (PPGLs) are considered malignant due to metastatic potential. Consequently, PPGLs are divided into «metastatic¼ and «non-metastatic¼. Metastatic PPGLs can be with synchronous metastasis (metastases appear simultaneously with the identified primary tumor) or metachronous (metastases develop after removal of the primary tumor). The term metastatic PPGLs is not used in the presence of tumor invasion into surrounding organs and tissues, without the presence of distant metastases of lymphogenic or hematogenic origin. It is generally believed that about 10% of pheochromocytomas and about 40% of sympathetic paragangliomas have metastatic potential. On average, the prevalence of PPGLs with the presence of metastases is 15-20%. Risk factors for metastatic PPGLs are widely discussed in the literature, the most significant of which are groups of clinical, morphological and genetic characteristics. The review presents a discussion of such risk factors for metastatic PPGLs as age, localization and type of hormonal secretion of the tumor, the size and growth pattern of the adrenal lesion, the presence of necrosis and invasion into the vessels, the tumor capsule surrounding adipose tissue, high cellular and mitotic activity, Ki-67 index, expression of chromogranin B and S100 protein, the presence of genetic mutations of three main clusters (pseudohypoxia, kinase signaling and Wnt signaling).Over the past two decades, a number of authors have proposed various predictor factors and scales for assessing a probability of metastatic PPGLs. The review contains detailed description and comparison of sensitivity and specificity of such predictor scales as PASS, GAPP, M-GAPP, ASES and COPPS.

[Comparison of the effectiveness of various methods for determining the level of metanephrines in the diagnosis of pheochromocytomas].

BACKGROUND: Pheochromocytoma (PHEO) is a tumor from the chromaffin tissue of the adrenal medulla, capable of hyperproduction of catecholamines. The increased production of hormones by the tumor leads to catecholamine crises, which have a pathological effect on all organs and systems. In the primary diagnosis of pheochromocytomas, it is important to determine the level of the metabolite of catecholamines - metanephrines. Currently, in clinical practice, various methods are used to determine the level of this metabolite: in blood plasma or in urine, total or only free form, fractionated analysis or unfractionated. AIM: Comparison of the effectiveness of various methods for determining the level of metanephrines for the diagnosis of pheochromocytomas. MATERIALS AND METHODS: A retrospective single-center cohort study was conducted on a sample of patients who were initially operated on for adrenal neoplasm at the Pirogov St. Petersburg State University High Medical Technology Clinic from November 2007 to December 2022 and who passed analysis to determine the level of blood or urine metanephrins before surgical treatment. The results of tests for metanephrine and tumor size were evaluated. RESULTS: 1088 patients with adrenal neoplasms who underwent surgical treatment were examined, of which 348 had histologically confirmed the presence of pheochromocytoma. Four types of metanephrine assays were compared: free fractionated plasma metanephrines (232 patients), unfractionated daily urine metanephrines (431 patients), fractionated total daily urine metanephrines (427 patients) and fractionated free daily urine metanephrines (178 patients). The greatest sensitivity was demonstrated by the analysis of free fractionated plasma methanephrines (95.4%). Unlike others, the sensitivity of this analysis did not decrease in the group of patients with small pheochromocytomas (3 cm or less). The greatest specificity was demonstrated by the analysis of unfractionated metanephrines in daily urine (97.8%), with the lowest sensitivity among all tests (67.6%). The study of fractionated total daily urine metanephrins showed good results of sensitivity and specificity, only slightly inferior to the best indicators, and the analysis of free daily urine metanephrins demonstrated unexpectedly low efficiency. There is a positive correlation between the level of metanephrine in the blood and the size of the tumor. CONCLUSION: Based on the data obtained, the preferred assays for the primary diagnosis of pheochromocytoma can be considered the determination of fractionated free plasma metanephrines and fractionated total daily urine metanephrines, which is consistent with relevant clinical recommendations. It was found that the size of the tumor correlates with the severity of an increase in the level of metanephrins determined by any of the described methods.