FP4.1 - Impact of adjuvant chemotherapy on the 5 Year Overall Survival for non-metastatic colon cancer patients in Bulgaria - a population wide based observational study

Abstract Aim Colon cancer patients who receive adjuvant chemotherapy later in life have lower survival rates. NCCN guidelines recommend the use of adjuvant chemotherapy for patients with non-metastatic colon cancer. Our study's objective was to examine how adjuvant chemotherapy affected the 5-year overall survival (OS) of patients diagnosed with non-metastatic colon cancer in Bulgaria. Methodology This is a retrospective population-wide observational analysis of 8968 cases that was reported as colorectal cancer (CRC) in the Bulgarian National Cancer Registry (BNCR) from 2015 to 2016. The mean and median ages of patients with right colon (RCC) and left colon (LCC) were examined. An analysis was conducted to determine the effect of adjuvant chemotherapy on the 5-year overall survival for non-metastatic colon cancer. To estimate the statistical significance, chi-squared tests, ANOVA, and the Kaplan-Meier curve with log rank were employed. Results In comparison to LCC, RCC had a higher mean age at diagnosis of 68.9 versus 67.41 (p-Value=<0.001). For RCC and LCC, the corresponding median ages at diagnosis were 69 and 68. The 5-year OS for patients with non-metastatic colon cancer who received adjuvant chemotherapy was higher than for patients who did not (67.8% vs. 59%, respectively, p-Value=0.007), according to our study. Adjuvant chemotherapy was given to slightly more than 30% of patients. Conclusion The 5-Year OS for patients with non-metastatic colon cancer is improved by adjuvant chemotherapy, and Bulgaria should follow NCCN guidelines. The implementation of a systematic screening program can be advantageous for Bulgaria as well.