Background: This is a single-center, prospective, observational study aiming to determine the effects of unidentified renal insufficiency (URI) on the safety and efficacy of chemotherapy for metastatic colorectal cancer (mCRC) patients.
Patients and methods: mCRC patients with normal serum creatinine and who were treated with CapeOx as the first-line therapy were included. Creatinine clearance (CrCL) was estimated using the Cockcroft-Gault formula. URI was characterized by a CrCL of less than 60 ml/min. Logistic regression was used to assess the effects of URI on toxicities and response rates. Kaplan-Meier curve was used to evaluate the effect of URI on survival.
Results: A total of 143 patients were enrolled, of whom 34.9 % had URI. Compared with the control group, the URI group had longer toxicity durations and developed significantly more grade 1 to 2 toxicities after adjusting for age, gender, and body mass index. The toxicities include cytopenia (76 vs. 61 %, OR = 1.86, 95 % CI = 0.39-2.53, P < 0.001), diarrhea (34 vs. 29 %, OR = 3.76, 95 % CI = 0.95-6.53, P = 0.007), stomatitis (10 vs. 6 %, OR = 2.81, 95 % CI = 1.10-4.28, P = 0.002), and hand-foot syndrome (18 vs. 11 %, OR = 2.56, 95 % CI = 0.86-5.41, P = 0.045). The response rate and time to progression were significantly lower in the URI group than in the control group (4.5 vs. 5.5 months, HR = 1.57, 95 % CI = 1.09-2.25, P = 0.015), whereas the overall survival rates of the two groups were similar.
Conclusion: In conclusion, URI can increase the toxicity and decrease the TTP of CapeOx-treated mCRC patients. Renal function screening via CrCL estimation is required for all mCRC patients before initial chemotherapy.