Ulcerative Colitis Related Colorectal Cancer Admissions—Insights From National Cancer Database

BACKGROUND: Ulcerative colitis is associated with higher risk of colorectal cancer. Crude annual incidence of colorectal is estimated around 0.06-0.16%. However, there is relative paucity of colorectal cancer related admissions in Ulcerative colitis on a national level. As such, we set out to determine the proportion of CRC-related hospital admissions in Ulcerative colitis along with outcomes over the last five years.

METHODS: This was a retrospective study utilizing the 2008-2014 National Inpatient Database Cohort for all principal discharges of Colorectal cancer in patients utilizing ICD 9 CM codes. Primary outcomes were the trends of colorectal cancer related admissions and trends in surgery related to colorectal cancer in patients with Ulcerative Colitis. Secondary outcomes were mortality, impact on healthcare utilization in terms of length of stay. These were then adjusted for confounders utilizing multivariate and Poisson regression analysis. All statistics were performed utilizing STATA software.

RESULTS: A total of 564,372 patients were admitted to a hospital with a principal diagnosis of CRC and captured by the NIS database. Out of these, 0.25% (1,459) of these admissions were related to UC. Although the number of hospitalized CRC patients decreased from 2010 to 2014 (114,038 to 110,475; P value = 0.002), the proportion of discharges with Ulcerative colitis related CRC have not changed significantly (0.25% in 2010 to 0.29% in 2014; P > 0.05). There was a similar trend for colorectal surgeries performed during the time period (overall 0.32%). There was significant difference in CRC related admissions with UC as compared to general population. UC related CRC was noticed in younger patients (61.31 years vs 67.17 years; P < 0.001). UC related CRC admissions were more likely males (60% vs 52%; P = 0.002). There has been no significant difference in ethnicity or regional admissions. UC related CRC was less likely to be associated with liver metastasis (4.65% vs 12.6%, P < 0.001) and lung metastasis (3.4% vs 3.8%; P = 0.001). CRC related admissions with UC were more likely to undergo colorectal surgery during the admission (75% vs 60%, P < 0.001). Similarly, the mortality in UC related CRC is significantly lower as compared to general population (0.65% vs 2.34%; P < 0.001). The healthcare utilization in terms of length of stay has been similar in both the cohorts.

CONCLUSION(S): There was a steady decrease in the number of hospitalized patients with colorectal cancer during the last several years, primarily attributable to a decrease in the older than 50 years age patients with colorectal cancer patients. This indirectly relates to the impact of colon cancer screening in the population above 50 years of age. However, UC related with CRC admissions have not witnessed the same decline over the last five years. Low frequency of liver and lung metastases indirectly indicate impact of surveillance in identifying cancer in early stage.