Dosing oxaliplatin in a haemodialysis patient with metastatic rectum cancer monitored by free platinum concentrations.

Dosing oxaliplatin in a haemodialysis patient monitored by free platinum concentrations was effective, safe and feasible in clinical practice. Further research is needed to determine the best pharmacokinetic parameter or combination of parameters and corresponding target values to further optimize the oxaliplatin dose for the individual haemodialysis patient.

A 77-year-old haemodialysis patient with metastatic rectum cancer was treated with FOLFOX and bevacizumab (oxaliplatin 70 mg/m² , folinic acid 200 mg/m² , 5-FU 340 mg/m² bolus and 2040 mg/m² continuous infusion during 44 hours and bevacizumab 5 mg/kg) every three weeks. Haemodialysis started immediately after infusion of oxaliplatin. The oxaliplatin dose was monitored by measuring free platinum ultrafiltrate concentrations. The AUC_0-50 of free platinum plasma ultrafiltrate after cycles 1-3, respectively, was 24.3, 24.7 and 25.8 μg*h/mL. The C_max was, respectively, 1.3, 1.3 and 2.2 μg/mL. There was no accumulation of free platinum detectable. The patient experienced no toxicity, and after 3 cycles, the CT scan showed a decrease in the liver metastases after which hemihepatectomy and metastasectomy were performed without any complications. A CT scan 6 months after the surgery showed no new liver metastases. However, lymphatic metastasis was diagnosed for which palliative treatment was started.

Oxaliplatin in combination with fluorouracil and folinic acid is one of the preferred chemotherapeutic options in the treatment of metastatic rectum cancer. However, oxaliplatin is contraindicated in patients with a creatinine clearance <30 mL/min and dosing guidelines in patients on haemodialysis have not been established.