For the first time, the prognostic value of heavy metals for recurrence-free survival in patients with CRC (using a regression model) was assessed: with chromium content (regression coefficient – 22.3) and zinc content (regression coefficient – 0.5), р<0,05; i.e., with an increase in the blood of patients with chromium and a decrease in zinc, there is a lower recurrence-free survival. Scientific data on the accumulation of heavy metals in patients with CRC tumour in correlation with unaffected tumour tissue of the colon and in the blood are the following: the zinc content in the tumour is 1.85 times higher than in unaffected tumour process of the colon (р<0,05). In patients with colorectal cancer, the content of chromium is 9 times, lead 8.6 times, cadmium 3.8 times, zinc 1.8 times and copper 1.5 times higher in the tumour than in the blood (р<0,001). It was determined that in patients with colorectal cancer in the unaffected colon, the content of chromium is 28.7 times, lead 2.8 times and cadmium 3.2 times higher than in the colon of healthy people (р˂0,001). Scientific data on the correlation of heavy metal content in the tumour-free colon of patients with colorectal cancer and healthy people are the following – chromium 28.7 times, lead 2.77 times and cadmium 3.2 times higher than in the colon of healthy people (р<0,001). Scientific data have been refined, which allowed developing additional prognostic factors for patients with CRC stage II, i.e. the determination of the content of chromium and zinc in the blood of patients with CRC by building a regression model (regression coefficient for chromium – 22.3 and for zinc – 0.5). Practical significance of the results. Additional prognostic factors in patients with colon cancer have been supplemented (determination of chromium and zinc in the blood of patients with colorectal cancer) to individualize the treatment of stage II colorectal cancer. An algorithm of diagnostic and treatment recommendations in patients with stage II CRC in addition to the generally accepted adverse prognostic factors according to NCCN recommendations (the degree of tumour differentiation, lymphatic and perineural invasion, the number of examined lymph nodes, intestinal obstruction and localized perforation) to determine additionally the level of chromium and zinc in the blood. For patients with high-risk CRC, chemotherapy is recommended if blood chromium levels are higher than 0.06 μg/g; and for low-risk patients, adjuvant chemotherapy is recommended if chromium levels are higher than 0.06 μg/g and zinc levels are less than 4.4 μg/g. Key words: colorectal cancer, heavy metals, adjuvant treatment of colon cancer, prognostic factors in colorectal cancer, chemotherapeutic treatment of colorectal cancer. Branch – medicine.
