Competing nomograms help in the selection of elderly patients with colon cancer for adjuvant chemotherapy

Purpose The extent to which ≥ 70 year patients with colon cancer benefit from adjuvant chemotherapy in the presence of competing risks remains controversial. Methods 18,937 patients ≥ 70 years with high-risk stage II and stage III colon cancer were retrospectively reviewed from SEER database. Propensity score matching (PSM) was used to adjust for potential baseline confounding. The nomograms were developed based on the competing model to describe the individual probability of colon cancer-specific death (CCSD) and non-CCSD. The subpopulation treatment-effect pattern plot (STEPP) was used to estimate the treatment-effect heterogeneity. Results In the high-risk stage II subgroup, compared to the non-recipients, the hazard ratios (HR) of overall mortality for recipients were 0.83 ( P = 0.001). The subdistribution hazard ratio (SHR) of CCSD for receipts was 1.22 ( P = 0.021). The SHR of non-CCSD was 0.63 ( P