The tumor cured, but what about the patient?

Abstract

Polyneuropathy is defined as a simultaneous malfunction of several peripheral nerves, which could be a toxic side effect of cancer therapy; however, this is reported to occur rarely and difficult to confirm. The purpose of the study was to introduce, at the first time, the calorimetry in the diagnosis of neuropathy in an experimental animal model. The study was inspired by the forensic investigation of a 53-year-old cancer survivor female patient, in whom the development of polyneuropathy could be caused by cyclophosphamide therapy. Adult guinea pigs were injected intraperitoneally with the dose of cyclophosphamide, comparable to the human dosage. Animals were euthanized, then nerve and muscle samples were analyzed using a SETARAM Micro calorimeter. Denaturation temperatures were measured and the calorimetric enthalpies were calculated based on the areas under thermal absorption curves. Thermal denaturations of the samples were decreased and the calorimetric enthalpies were increased depending on the doses of cyclophosphamide. The nerves were more sensitive to chemotherapy as compared to the muscles. It is concluded that toxic effects of cyclophosphamide on peripheral nerves and muscles can be measured and analysed by calorimetry, and that the effect was dose dependent.