Study to Evaluate the Use of Capecitabine in Monotherapy and in Combination With Oxaliplatin in Elderly Patients as Adjuvant Chemotherapy for Locally Advanced Colorectal Cancer.

Inclusion Criteria: 1. Age 70 years and older; 2. Obtaining informed consent to participate in the study; 3. Morphologically confirmed diagnosis of colorectal cancer; 4. Stage III colorectal cancer; 5. Underwent radical surgical intervention for primary colorectal tumor; 6. ECOG score of 0 - I; 7. Life expectancy of more than 6 months; 8. No history of systemic drug therapy for CRC; 9. Adequate liver, kidney and bone marrow function; 10. Absence of severe uncontrolled concomitant chronic diseases and acute illnesses. Exclusion Criteria: 1. Having previously received any systemic therapy for CRC; 2. Time after surgical treatment of more than 12 weeks; 3. Stage I-II and IV disease; 4. Confirmed dihydropyrimidine dehydrogenase deficiency in blood by PCR (alteration of alleles c.\[190511G \> A\], c.\[1679T \>G\],\[2846A \> T\], \[1129-5923C \>G\], \[c.1236 G\>A(HapB3)\]); 5. Severe uncontrolled comorbid chronic diseases or acute illnesses; 6. Presence of a second malignancy (except for previously cured malignancies); 7. Any condition that, in the opinion of the physician, would interfere with the study procedures.