Extensive investigation of neuroendocrine tumors (NETs) has only started in recent years. The increased attention to this issue is due to the more frequent detection of NETs as a result of diagnostic methods improvement.The limited effectiveness of chemotherapy for well-differentiated advanced metastatic NETs of gastrointestinal tract (GIT) and pancreas demonstrates the need for development of the new and more effective treatment options.Recent studies on specific biological features of NETs have led to the development of the new targeted therapies which take into account high vascularization and overexpression of specific growth factors and related tyrosine kinase receptors. Thus, studying the mTOR TSC2, PTEN and PIK3CA signaling pathways opens up the new opportunities in the treatment of gastrointestinal or pancreatic NETs, especially in case of inoperable or metastatic tumors. Targeted therapy, which specifically inhibits growth factor receptors and related signaling pathways, is a promising approach to drug therapy for patients with gastrointestinal or pancreatic NETs.This review summarizes the state of the art and prospects for using targeted therapy, and describes clinical studies in the treatment of gastrointestinal and pancreatic NETs.

Background: Neuroendocrine tumors (NETs) are one of the most poorly studied neoplasms today. At the same time, the interrelation between hereditary mutations in genes of the repair system of DNA and NETs is not well-studied.Our aim was to carry out an analysis of the occurrence of mutations in genes of the repair system of DNA in patients with NETs.

The incidence of neuroendocrine tumors has significantly increased over the last years.The purpose of the study was to analyze treatment outcomes in patients with pancreatic endocrine tumors (PETs) with regard to histopathologic diagnosis.Material and Methods. The clinical records of 1077 patients with pancreatic tumors were retrospectively analyzed. Fifty patients were diagnosed with PET. Treatment outcomes were assessed with regard to tumor differentiation grade, tumor stage, extent of surgery and drug therapy.Results. The most common histological grade was G1. Patients with G1 tumors had the best 1-and 3-year survival rates regardless of tumor stage. Factors influencing prognosis in patients with PETs were: radical surgery, Ki67 expression level, histological grade (G1–3), tumor stage at diagnosis.

Рост заболеваемости нейроэндокринными опухолями увеличивает интерес к изучению генетического ландшафта новообразований. В большей степени нейроэндокринные опухоли (НЭО) исследованы в контексте наследственных генетических синдромов, включая гены, такие как MEN1, VHL, TSC1 / TSC2, NF1 и CDKN1B. Взаимосвязь между наследственными (генеративными) мутациями в генах системы репараций ДНК и нейроэндокринными опухолями на сегодня практически не изучена.В условиях ГАУЗ «Республиканский клинический онкологический диспансер Министерства здравоохранения Республики Татарстан имени профессора М. З. Сигала» был изучен молекулярный профиль пациентов с диагнозом «нейроэндокринная опухоль» в зависимости от наследственного анамнеза. В проведенном исследовании у каждого четвертого пациента обнаруживались патогенные мутации. У 33 % пациентов при наличии наследственного анамнеза выявлены патогенные, либо условно-патогенные мутации