Endocrine Abstracts

Adrenocortical cancer (ACC) is a tumor of the adrenal cortex, clinical manifestations, recurrence, and progression potential are determined by its biological characteristics. Morphological diagnosis of tumors of the adrenal glands in some cases presents significant difficulties. According to the WHO classification of tumors of the endocrine organs (4th revision, 2017), in addition to the classical one, myxoid, sarcomatoid and oncocytic histological variants of ACC are distinguished. According to a number of studies, the oncocytic variant is characterized by a less aggressive clinical course. In our work, we present a clinical case of combined treatment of two-component hormonally active (hypercorticism and virilization) adrenocortical carcinoma. After radical surgical treatment, histological examination was verified a polyclonal adrenocortical carcinoma, represented by two components different in cellular composition and architecture. Most of the tumor is of classical structure (Weiss score 4), the second component is an oncocytic variant of ACC (2 major and 2 minor Lin-Weiss-Bisciglia criteria). An immunohistochemical (IHC) study of the oncocytic component of tumor revealed expression of subtype somatostatin 2 receptors (SSTR2), KI67 index was 21%. There was no expression SSTR2 in classical component, the Ki67 proliferation index was 10%. Chromogranin A expression was absent in both tumor components. Invasion of periadrenal adipose tissue, Ki67 10% or more in both tumor components, positive expression of SSTR2 served as the basis for starting adjuvant drug treatment with mitotane in combination with long-acting somatostatin analogs. There was no progression of the disease during 30 months of patient monitoring. To date, mitotane remains the only drug for the treatment of ACC with proven efficacy. A number of targeted drugs interacting with specific tumor receptors have been proposed, but their use is limited a low efficiency. Recently, reports have been published on the expression of SSTR in tumor tissue, as well as on the effect of synthetic somatostatin analogs on the growth of ACC cell lines. A feature of this clinical case is the development of polyclonal adrenocortical carcinoma, with different functional activity, histostructure, proliferation index and receptor status of its components, which suggests a different malignant potential of tumor components and emphasizes the need for accurate morphological verification of adrenocortical tumors for individualization of treatment. The progression-free period more than 30 months after radical surgical treatment gives grounds for the use of somatostatin analogs in the drug treatment of ACC, but its effectiveness requires further study and evaluation.