Serine-threonine inhibitors, such as vemurafenib, are being used increasingly in cancer treatment, and the toxicity and therapeutic benefit need to be balanced carefully both before and during treatment.
A patient with metastatic melanoma and end stage renal failure who was on peritoneal dialysis was treated with the serine-threonine kinase inhibitor, vemurafenib. After 5 months of treatment, a substantial response to vemurafenib was observed using imaging, but when he developed a prolonged QTc interval (common toxicity criteria (CTC) grade 3), treatment was interrupted. Vemurafenib was restarted at a reduced dose when the QTc interval returned to normal. The patient has had a significant response to vemurafenib and continued on treatment for 12 months after beginning the therapy.
This is the first reported case of end stage renal failure in a patient who is taking vemurafenib. Although the patient developed QTc prolongation, it appears to be asymptomatic, and was managed with dose reduction. This case highlights the need for closer QTc monitoring at the start and during treatment.
