EP673 - Nationwide Trends in Mortality and Morbidity After Colorectal Cancer Surgery in Korea: A Population-Based Analysis Using National Health Data (2007–2017)

Purpose/Background: Understanding long-term surgical outcomes in colorectal cancer (CRC) is essential for improving perioperative care and national cancer strategies. This study aimed to describe nationwide trends in postoperative mortality and morbidity among Korean patients undergoing colorectal cancer surgery using a population-based database.

Methods/Interventions: We analyzed nationwide claims data from the Korean National Health Insurance Service (2007-2017), including 214,407 patients with colorectal cancer (ICD-10 C18-C20) who underwent surgery. The main outcomes were 1- and 5-year postoperative mortality after the first colorectal resection, with age-standardized mortality calculated using the 2010 Korean standard population. Surgical procedures were classified as standard or extended colectomy, local excision, sphincter-preserving, and sphincter-sacrificing rectal resection. Mortality rates were estimated for specific procedure types, particularly for major procedures. In addition, total postoperative complications and postoperative bleeding were analyzed in relevant procedure groups.

Results/Outcomes: The overall 1-year mortality gradually decreased from 7.5% in 2007 to 7.3% in 2017, while 5-year mortality declined from 27.9% to 26.6% during the same period. Mortality was strongly associated with age: 1-year mortality increased from 3.9% among patients in their 60s to 15.5% in those aged ≥80 years, and 5-year mortality reached 45.4% in the oldest group. Age-standardized mortality showed a U-shaped pattern in both sexes, with the lowest rates among patients aged 50-60 years. Across procedure types, extended colectomy and sphincter-sacrificing rectal resection showed the highest 1-year mortality (up to 26% and 17%, respectively), whereas local excision consistently demonstrated the lowest ( < 1%). Despite stable national surgical volume, age-standardized mortality modestly declined across most procedures.

Conclusion/Discussion: This large, population-based analysis provides a comprehensive overview of colorectal cancer surgical outcomes in Korea. Although national postoperative mortality has gradually improved, elderly patients and those undergoing extensive resections remain at high risk.

The age-standardized mortality rate according to each surgery type
(A) 1-year overall mortality, (B) 5-year overall mortality. SC-standard colectomy, EC-Extended colectomy, LE-Local excision of rectal tumor, RP-Rectal resection (Sphincter preserving), RC-Rectal resection (Sphincter sacrificing)


The age-standardized mortality rate according to age group
(A) 1-year mortality rate, (B) 5-year mortality rate.