Surgical Approach as a Mediator of Rural-Urban Disparity after Colon Cancer Resection

Abstract

Background: Rural populations experience higher colon cancer (CC) mortality than urban populations, and rural patients may have more complications after resection. Reoperations due to complications after CC resection among rural and urban patients are not clear, and factors mediating disparities in rural-urban postoperative outcomes have not been examined.

Study design: Using the Surveillance, Epidemiology, and End Results Program-Medicare database, individuals with CC who underwent surgical resection were compared via multivariable logistic regression to determine the association of rurality with postoperative complications and reoperations at 30, 60, and 90 days. A 4-way effect decomposition (mediation analysis) assessed how surgical approach (open vs minimally invasive surgery [MIS]) mediated the relationship between rurality and complication risk. Survival was assessed at 30 days, 90 days, and 1 year.

Results: Among 33,183 patients, rural patients (n = 5,938; 18%) had lower Charlson Comorbidity Indices (p < 0.0001) and presented less emergently (p = 0.0307); stage did not differ from urban patients. Rural patients underwent more postdischarge reoperations (p = 0.0007) and had higher odds of surgical site infection (SSI; odds ratio [OR] 1.31, 95% CI 1.13 to 1.52) and anastomotic leak (OR 1.19, 95% CI 1.07 to 1.33). Rural individuals were less likely to undergo MIS (OR 0.67, 95% CI 0.63 to 0.72); MIS was associated with lower odds of SSI (OR 0.58, 95% CI 0.51 to 0.67) and leak (OR 0.57, 95% CI 0.52 to 0.63). Surgical approach mediated 29% of the overall complication risk, 18% of the SSI risk, and 28% of the anastomotic leak risk for rural patients. Finally, survival was lower among rural patients (30 days: p = 0.0313; 90 days: p = 0.0195; 1 year: p = 0.0063).

Conclusions: Surgical approach mediated one-third of the complication risk experienced by rural patients, who had higher odds of complications, more postdischarge reoperations, and lower odds of accessing MIS. Expanding rural MIS colectomy practices may be one way to achieve more geographically equitable outcomes.