Objective: To compare the 3-year disease-free survival (DFS) of stage II and III colorectal cancer (CRC) patients receiving oxaliplatin (Ox)-based and fluoropyrimidine (FP)-based chemotherapy as the adjuvant chemotherapy. The outcomes of patients with rectal cancer and stage IV CRC patients receiving palliative chemotherapy were determined. The sidedness as a prognostic factor of survival in patients with stage III colon cancer was evaluated.

Materials and Methods: A retrospective analysis of CRC patients attending Vajira Hospital between January 1, 2010 and December 31, 2014 was performed.

Results: There were 523 participants. The median follow-up was 68.9 months. One hundred-eighty-one colon cancer patients (both stage II and III) had received adjuvant chemotherapy. Adjuvant Ox-based chemotherapy (n=93, 3-year DFS 66.3%, 95% CI 54.77 to 75.46) was not superior to FP (n=88, 64.2%, 95% CI 51.49 to 74.36), p=0.567. Among patients with rectal cancer, adjuvant post-operative Ox-based regimen was not superior to FP. Adjuvant radiotherapy led to insignificant benefits in terms of DFS and overall survival (OS). Most of the rectal cancer had distant sites of recurrences. Patients with stage III right-sided colon cancer had a trend towards worse OS compared to the left-sided ones.

Conclusion: In the real-world clinical practice, the outcomes of CRC treatment may be inferior to the pivotal clinical trials.

Keywords: Colorectal cancer, Adjuvant, Oxaliplatin

Received 18 Feb 2019 | Revised 8 Aug 2019 | Accepted 13 Aug 2019