BackgroundThe recent staging manual upstages Node-negative tumor-deposit positive colorectal cancer (CRC) from N0 to N1c category, while the development of tumor-deposit presence is poorly understood. Meanwhile, Kras mutation is associated with progression of CRC, but its link to tumor-deposit status is unclear.
MethodThis retrospective cohort study included the patients with incidental CRC diagnosed during 2010-2014 in the National Cancer Database and recorded statuses of Kras and tumor deposit. We conducted multivariable logistic regression and Cox regression analyses to investigate the factors associated with tumor-deposit status and overall-survival, respectively.
ResultsA total of 48,200 CRC patients with Kras status were included in the study (25,407 [52.7%] men, 25,648[46.8%] <65 years old, 18 381 [38.1%] with Kras mutation). Adjusted for microsatellite instability, age, pathologic stage and tumor grade, Kras mutation (versus wild-type) was associated with tumor-deposit presence (n=15,229, odds ratio=1.11, 95% CI 1.02 to 1.20). Kras mutation was also independently linked to a worse overall survival of CRC patients regardless of tumor-deposit status (n=8,110, adjusted Hazard ratio=1.40, 95% CI 1.09 to 1.79 for CRC with tumor deposits, and n=2,618, adjusted HR=1.63, 95% CI 1.16 to 2.28 for CRC without), but a better survival in CRC with no known/applicable tumor-deposit status (n=457, adjusted Hazard ratio =0.32, 95% CI 0.11 to 0.95).
ConclusionKras mutation is independently associated with tumor-deposit presence, and a worse overall survival of CRC with or without tumor-deposit. Therefore, it may play a role in the development of tumor deposits and serve as a target for CRC treatment.
