91P - Adjuvant therapy for high-risk stage II or stage III colon adenocarcinoma: A propensity score-matched, nationwide, population-based cohort study

Background

To estimate the optimal adjuvant chemotherapy in patients with high-risk stage II and III colon adenocarcinoma, we use a propensity score-matched (PSM), nationwide, population-based cohort study to estimate different adjuvant treatments in high-risk stage II or stage III colon adenocarcinoma.

Methods

We minimized the confounding effects with PSM of sex, age, pathologic stages, tumor locations, total cycles of chemotherapy, and Charlson comorbidity index in various adjuvant treatments outcomes in patients with high-risk stage II and III resctable colon adenocarcinoma from the Taiwan Cancer Registry database by dividing them as follows: group 1, those undergoing surgery alone; group 2, those undergoing adjuvant fluoropyrimidine alone; group 3, those receiving adjuvant oxaliplatin, fluoropyrimidine, and leucovorin (FOLFOX) and group 4 those receiving adjuvant folinic acid, fluorouracil, irinotecan (FOFIRIL).

Results

In both univariate and multivariate Cox regression analyses, adjusted HRs (aHRs) derived for mortality and 95% confidence intervals (CIs), reported as aHR (95% CI), derived for surgery alone, adjuvant fluoropyrimidine alone, and adjuvant FOLFIRI groups compared with the adjuvant FOLFOX group were 1.55 (1.32-1.82), 1.22 (1.05-1.43), and 2.97 (2.43-3.63), respectively. After stratified subgroup analysis, at high-risk stage II, the aHR (95% CI) derived for mortality was 0.52 (0.30-0.89) for the adjuvant fluoropyrimidine alone group compared with the group 3.

Conclusions

Adjuvant fluoropyrimidine alone were more suitable for patients with high-risk stage II colon adenocarcinoma rather than other adjuvant chemotherapy regimens. Adjuvant FOLFOX could be the optimal regimen for patients with pathologic stage III colon adenocarcinoma whatever elderly, sex, or tumor locations.

Clinical trial identification

Editorial acknowledgement

Legal entity responsible for the study

The authors.

Funding

Has not received any funding.

Disclosure

All authors have declared no conflicts of interest.