Endoscopic semiotics and diagnostics of rectal neuroendocrine tumors

Aim. To evaluate the role of endoscopic techniques in the diagnosis of neuroendocrine tumors of the rectum, as well as to determine the features and symptoms characteristic of these tumors.

Methods. An analysis of patients diagnosed with R-NETs examined at the N.N. Blokhin NationalMedical Research Center of Oncology over the past year and a half was conducted. The followingdata were established: the average size of the formations, their most common localization, theaverage proliferation index and the preferred method of treatment.

Results. The average follow-up period was 25 months. The median age was 47,5 years. All patientsunderwent colonoscopy using clarifying diagnostic techniques. In 57% of cases, tumors were localized in the middle ampullary section of the rectum, in 32% in the lower ampullary section, andin 11% in the upper ampullary section. The average size of the formations was 9 mm.According tothe results of histological examination, type 1 according to the WHO classification was identified in73% of cases, and type 2 in 27% of cases. All patients underwent surgical treatment. There wereno signs of disease progression at the time of evaluation of the results.

Conclusion. According to the latest data, there is currently no single tactic for managing patients with neuroendocrine tumors, and the existing diagnostic and treatment plan is a multidisciplinary comprehensive approach. The choice of an adequate volume of surgical intervention depends on the correct endoscopic assessment of the tumor, which allows suspecting the neuroendocrine nature of the formation before its removal. The widespread introduction of colonoscopy as a screening method allows increasing the detection rate of such rare formations as neuroendocrine tumors of the colon, as well as increasing the awareness of endoscopists in recognizing neuroendocrine tumors of the rectum.

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