The impact of kidney function on colorectal cancer patients with localized and regional diseases: An observational study from Taiwan

BACKGROUND: Impaired kidney function is associated with different diseases. However, its impact on colorectal cancer has not been clarified. In order to understand the effect of preoperative kidney function on the outcome of patients with cancer, we analyzed colorectal cancer patients with localized or regional diseases. MATERIALS AND METHODS: In total, 3731 stage I to III colorectal cancer (CRC) patients were analyzed in Chang Gung Memorial Hospital. Modification of Diet in Renal Disease (MDRD) formula was used for estimated glomerular filtration rate (eGFR). Receiver operating characteristic (ROC) analysis for kidney function cut-off value; Chi-square method, independent t test, or analysis of variance (ANOVA) method for clinicopathological factors; KaplanuMeier method for disease-free survival (DFS); Cox proportional hazard model for multivariate analysis. RESULTS: Among colon cancer patients, low eGFR (MDRD <70) was associated with more male patients, T2 stage, patients without adjuvant chemotherapy, and patients with elevated creatinine level. Low eGFR is a significant risk factor only for stage III colon cancer (hazard ratio 1.70, 95% CI: 1.28u2.26; P < 0.001). Furthermore, postoperative adjuvant chemotherapy did not significantly increase 5-year DFS for both high and low eGFR groups in stage II patients (5 yrs DFS, 94.8% vs. 84.1%, P = 0.098 for high eGFR subgroup; and 75.0% vs. 75.8%, P = 0.379 for low eGFR subgroup). However, significant improvement of 5-yrs DFS after chemotherapy was found in low eGFR stage III colon cancer patients (64.7% vs. 39.4%, P < 0.001 for low eGFR subgroup). In contrast, no significant DFS difference was caused by chemotherapy for high eGFR stage III subgroup (70.5% vs. 63.9%, P = 0.110). CONCLUSIONS: Although low eGFR is an independent risk factor for stage III colon cancer. However, the adjuvant chemotherapy impacts on stage III colon cancer patients differently according to eGFR status.