PROGNOSTIC SIGNIFICANCE OF THE E-CADHERIN EXPRESSION LEVEL IN PRIMARY TUMORS OF THE COLON IN PATIENTS WITH METASTATIC COLORECTAL CANCER, RECEIVED NEW CHEMOTHERAPY REGIMEN BASED ON TRIPLE COMBINATION: IRINOTECAN+OXALIPLATIN+CONTINUOUS-INFUSION 5-FLUOROURACIL AS A FIRST-LINE TREATMENT

Background. The use of clinical and morphological characteristics is not enough to predict the prognosis of the disease in patients with metastatic colorectal cancer (mCRC). Aggressiveness of the tumor process can be significantly different in patients with similar clinical and morphological signs of the disease. It is assumed that these differences are due to the molecular biological features of the tumor and are additional factors predicting the survival of patients. Objective. Evaluation of the prognostic significance of the e-cadherin expression level in the primary tumors of the colon in mCRC patients who received a new chemotherapy regimen (CT) based on the triple combination: irin otecan+oxaliplatin+continuous-infusion 5-fluorouracil as 1st line treatment. Methods. The study included mCRC patients who received a new CT regimen based on the triple combination: irinotecan+oxaliplatin+continuous-infusion 5-fluorouracil as the first-line treatment. The evaluation of immediate and long-term results of treatment was carried out. In the tissue of the primary tumor of the colon (biopsic or surgical material) obtained before the start of the first-line therapy, the expression level of molecular-biological marker e-cadherin was estimated using immunohistochemical method. The obtained data on the e-cadherin expression were compared with immediate and long-term results of treatment. Results. In 18 of the 20 patients included in the study the immunohistochemical method was used to analyze the expression of e-cadherin in the tissue of the primary colon tumor, the Association of this marker with the prognosis of the disease, was analyzed. When analyzing the effect of e-cadherin expression in the tumor on the time-to-progression (TTP) in mCRC patients against the background of the first-line CT using a triple combination, it was found that high expression of this marker is a favorable factor predicting an increase in the TTP: median TTP in patients with overexpression e-cadherin of the tumor was significantly higher than in patients with low/no e-cadherin expression - 12.1±3.23 vs. 7.8 months. When analyzing the effect of e-cadherin expression in the tumor on the overall survival (OS) in mCRC patients, a statistically significant increase in OS was observed in the group of patients with overexpression e-cadherin (with median follow-up period 17.3 months, median OS was not achieved [75% of patients are alive], mean OS - 27, 85±3,23 months) compared with the group of patients with low/no e-cadherin expression of the tumor (median OS - 9.0 months). Conclusion. E-cadherin overexpression in the primary tumor tissue is a factor for favorable prognosis of TTP and OS in mCRC patients who received a triple combination CT as the first- line treatment. This marker can already be used today in real clinical practice for individual prognosis of the disease course in mCRC patients.

metastatic colorectal cancer, e-cadherin, 1st line treatmenT, chemotherapy, molecular-biological markers