Early-onset colorectal cancer: 2-year analyses of Georgian cancer registry.

Abstract

e15645 Background: Incidence of early onset colorectal cancer (EOCRC) is rising. Young patients (age < 50) are often diagnosed with stage IV and aggressive disease. Younger age in stage 3 CRC is negatively prognostic and associated with higher relapse rates and risk of death. Colorectal cancer screening is operating in Georgia since 2011 but referral is low. Incidence and characteristics of EOCRC have not been studied in Georgia. Methods: Data from Georgian cancer registry including 2022-2023 years were reviewed: these includes prospectively collected number of cases, age, sex, location, stage, pathology, grade, treatment. The study aimed to investigate clinicopathologic characteristics, treatment approaches, survival rates of EOCRC compared to Late onset colorectal cancer (LOCRC) (age > 50). Results: A total of 751 patients with CRC were identified. 59 (8%) were < 50 (median age 45). Left sided colon cancer was more common than right sided in both groups (37%vs27% in EOCRC; 62%vs27% in LOCRC). Stage III - IV was most frequent in both groups - stage III 44% in EOCRC vs 33% in LOCRC, stage IV 19% vs 24%. ( p value 0.0214). Adenocarcinomas (ADK) were 74% in EOCRC vs 75% in LOCRC. Rate of mucinous ADK was higher in EOCRC 10% vs 3% (p value 0.001). In both groups 20% were undefined carcinomas and 5% - rare histologies. Young adults with stage II/III rectal cancer had more radiation therapy (RT) (70% vs 19% for stage II; 62% vs 34% for stage III) and with stage II/III colon cancer had more chemotherapy (CT) than elderly (84% vs 41% for stage II; 69% vs 45% for stage III). Median survival was undefined for most comparisons except for EOCRC in Stage IV (24 months) HR- 0.66 (CI - 0.25 - 1.71 p-value 0.08). Data on molecular characteristics, recurrence, cause of death is not included in registry. Conclusions: This study showed that in Georgia patients with EOCRC have higher rates of mucinous ADK. Stage III is most common in EOCRC. Young patients with early-stage rectal cancer have more RT, those with early-stage colon cancer have more CT compared to elderly. Survival data is immature but median survival for stage IV EOCRC is low. Although with limitations this is the first evaluation of EOCRC from the Georgian cancer registry with potential to inform if incidence trends and patients characteristics follow the same patterns as Western countries.