High Risk Stage 2 and Stage 3 Colon Cancer, Predictors of Recurrence and Effect of Adjuvant Therapy in a Nonselected Population.

Patients with stage 2 and stage 3 colon cancer often are treated with adjuvant chemotherapy. However, patients seen in daily practice have more comorbidity than those enrolled in clinical trials. This study aims to evaluate prognostic factors for recurrence and to ascertain the benefit of adjuvant chemotherapy on recurrence-free survival (RFS) of patients in a nonselected population. Furthermore, the impact of relative dose intensity (RDI) of adjuvant therapy on RFS is examined. Chart review was performed for 243 consecutive patients diagnosed and treated at a single center for stage 2 and stage 3 colon cancer from 2002 to 2008. Adjuvant chemotherapy was administered to 66 patients. Median overall survival (OS) was 5.84 years and median RFS was 5.37 years. For stage 2 disease, patients treated with or without adjuvant therapy had a median RFS of 5.49 and 5.73, respectively (p = ns). For stage 3 disease, median RFS rates were 5.08 and 1.19, respectively (p = 0.084). Overall RDI of oxaliplatin based chemotherapy higher than median was associated with increased RFS (p = 0.045). In conclusion, adjuvant therapy did not significantly increase recurrence-free survival. This could be the result of comorbidity in patients. Relative dose intensity of oxaliplatin based therapy is associated with RFS.