Background: Oxaliplatin-based adjuvant chemotherapy has been applied as standard treatment for high risk stages II and III colon cancer in many countries. There was no comprehensive report of oxaliplatin use in Indonesia. This research aimed to evaluate the short-term survival of patients with colon cancer treated with such strategy and the prognostic factors.
Methods: Medical records of patients with colon cancer receiving oxaliplatin-containing adjuvant chemotherapy were retrospectively reviewed. Demography, clinicopathological, and treatment data were collected. Two-year overall survival (OS) and disease-free survival (DFS) were calculated using Kaplan-Meier method and survival predictors were estimated using Cox proportional hazard models.
Results: Data of 81 patients had been included with a median follow-up of 25.2 months. The estimated OS and DFS at 2 years were 75.8% and 72.7%. In multivariate analyses, the Eastern Cooperative Oncology Group (ECOG) 2 performance status [hazard ratio (HR) =2.967; 95% confidence interval (CI), 1.265 to 6.957; P=0.012], T4 stage (HR =2.669; 95% CI, 1.087 to 6.557; P=0.032), and less cycles of chemotherapy administration (HR =3.280; 95% CI, 1.333 to 8.070; P=0.010) were significant independent factors for an increased risk of death. Cases with moderately to poorly differentiated tumors had significantly worse DFS compared with those with well differentiated tumors (HR =3.503; 95% CI, 1.403 to 8.744; P=0.007).
Conclusions: Colon cancer patients receiving oxaliplatin-based adjuvant regimens in our clinical practice had 2-year OS rate of 75.8% and 2-year DFS rate of 72.7%. ECOG 2 performance status, T4 stage, and less cycles of chemotherapy administration significantly predicted a poor OS and moderately to poorly histological grade significantly predicted a poor DFS.
Keywords: Oxaliplatin; adjuvant chemotherapy; colon cancer; short-term survival.