Establishment of nedaplatin safety dose formula based on renal function for combination chemotherapy with nedaplatin and 5-fluorouracil in patients with esophageal cancer.

ABSTRACT

BACKGROUND: It is known that the area under the plasma concentration curve of nedaplatin (AUCNDP) is associated with the relative reduction ratio of platelets and that the AUCNDP is based on nedaplatin dose normalized by creatinine clearance (CrCL) (AUCdose/CrCL). Based on these relationships, in this retrospective study, we aimed to determine the unestablished doseNDP safe for patients with impaired renal function who received an initial combination chemotherapy with nedaplatin and 5-fluorouracil. METHODS: We performed a retrospective cohort analysis of consecutive patients with esophageal cancer who received an initial combination chemotherapy with ≤ 90 mg m-2 day-1 of nedaplatin on day 1 and 800 mg m-2 day-1 of 5-fluorouracil on days 1-5. AUCdose/CrCL was estimated using the formula, 3.2134 × doseNDP/CrCL + 4.4185. Data obtained during the first 28 days following nedaplatin administration were analyzed to compare AUCdose/CrCL between the patients with and without grade ≥ 3 thrombocytopenia. Receiver-operating characteristic (ROC) curve analysis was performed to determine the optimal AUCdose/CrCL cutoff value. RESULTS: Of the 136 patients included in this study, 8 (5.9%) presented with grade ≥ 3 thrombocytopenia. There were statistically significant differences in the AUCdose/CrCL between the patients with and those without grade ≥ 3 thrombocytopenia (11.79 vs. 10.09 µg h-1 mL-1; P = 0.00828). We found that the appropriate cutoff value for the AUCdose/CrCL using the ROC curve was 10.945 µg h-1 mL-1. CONCLUSIONS: Our results indicate that safe doseNDP should be estimated to satisfy the following formula DoseNDP (mg) < CrCL × 2.031.