Evaluation and monitoring of peripheral nerve function

The peripheral nervous system may be involved in several pathological events in patients with cancer and, in some cases, the evaluation and monitoring of nerve damage can be difficult. The target of drug-induced neurotoxicity is mostly dependent on the type and distribution of each substance that can act predominantly on the nerve fibers (axon or myelin) or on the neuronal body (dorsal root ganglia, primary sensory neurons, or, very occasionally, motor neurons). Accordingly, the clinical features of drug-induced neuropathies are also dependent on the type of agent involved, inducing exclusively sensory or sensorimotor neuropathies, with or without autonomic impairment and pain. Neurotoxic antineoplastic agents represent a major clinical problem given their widespread use, the potential severity of their toxicity, and the obvious reluctance of oncologists to change effective schedules of treatment despite the occurrence of side-effects. In view of the above, it is clear that chemotherapy-induced peripheral neurotoxicity should be assessed carefully and reliably. The most suitable tool for assessing and monitoring the neurotoxic effect of antineoplastic agents should be clinically relevant, fast and easy to use, reliable and reproducible, specific and sensitive to severity changes, formally validated, and universally accepted, and patients should be highly compliant with its items. The major advantages and limitations of the different methods used to evaluate and monitor peripheral nerve function in patients with cancer are discussed, with particular reference to the features of chemotherapy-induced peripheral neurotoxicity.