METHOD FOR PREDICTING THE ONCOLOGICAL EFFECTIVENESS OF CYTOREDUCTIVE OPERATIONS IN PATIENTS WITH STAGE IV COLON CANCER WITH UNRESECTABLE LIVER METASTASES

FIELD: medicine.SUBSTANCE: invention relates to medicine, namely oncology, and can be used to predict the oncological effectiveness of cytoreductive operations in patients with stage IV colon cancer with unresectable liver metastases. An immunohistochemical assessment of the proliferative activity of cancer stem cells and the expression level of the CXCR4 chemokine receptor is carried out. After colon adenocarcinoma biopsy, preparations are made for immunohistochemical examination using appropriate antibodies, which are studied using light microscopy. The expression of the CXCR4 chemokine receptor is estimated as the proportion of positive cells per 500 counted and interpreted as follows: low less than 30%, average from 30 to 70%, high 70-100%. The study of the proliferative activity of cancer stem cells is carried out using the method for double immunohistochemical staining using rabbit monoclonal antibodies to aldehyde dehydrogenase and mouse antibodies to protein Ki-67, from which a mixture is prepared in a ratio of 1:1, after which the resulting cocktail is applied to the test samples. Stem proliferating cancer cells are identified by their characteristic color: a brown nucleus against a bright pink cytoplasm, then their share in the general population is determined. In cases when it exceeds 50%, the proliferative activity of stem cancer cells is estimated as high, at a value of 10-50% as average, and at a value of this indicator of less than 10% as low. The score of the results obtained is estimated as follows: low, medium and high levels of CXCR4 expression and proliferative activity of stem cancer cells are estimated as 1, 2 and 3 points, respectively. The points received are summed up, after which the final interpretation of the results is made. The sum of points equal to 6 is regarded as a predictor of an unfavorable prognosis of cytoreductive operations in patients with stage IV colon cancer with unresectable liver metastases. The sum of points 4-5 is interpreted as an intermediate forecast. The sum of points 3 or less is regarded as a factor for a good forecast.EFFECT: method makes it possible to choose surgical tactics taking into account the molecular biological properties of the tumor by immunohistochemical assessment of the proliferative activity of cancer stem cells and the expression level of the receptor for CXCR4 chemokines, which makes it possible to assess the potential of tumor aggressiveness and increase the effectiveness of surgical