Chemotherapy-induced neuropathy: A comprehensive survey

Chemotherapy induced peripheral neuropathy (CIPN) is a potentially dose limiting side effect of commonly used chemotherapeutic agents like taxanes, vinca-alkaloids, platinum compounds, bortezomib and thalidomide. Supposed pathogenetic mechanisms of CIPN are axonopathy through dying back axon damage and neuronopathy in which the cell bodies of the dorsal root ganglia are involved. The exact pathophysiology however is not clear and different underlying mechanisms have been proposed for different classes of anti-cancer drugs. Sensory symptoms, like pain, numbness and tingling are most common, but motor weakness, autonomic dysfunction and even cranial nerve involvement may occur. CIPN can be painful and/or disabling, causing significant loss of functional abilities and decreasing quality of life. This can lead to dose reductions, discontinuation of treatment and may thus, ultimately, affect survival. Risk factors for CIPN include dose per cycle, cumulative dose, treatment schedule, duration of infusion, administration of other chemotherapeutics, comorbidity and pre-existing peripheral neuropathy. The exploration of polymorphisms in genes associated with incidence or severity of neuropathy might result in identifying individuals being at higher risk of neurotoxicity. An update on genes possibly associated with CIPN is given. CIPN may be reversible or be more or less permanent. Many preventive and treatment strategies have been explored, without significant efficacy up till now. In this review we describe the different drug-related characteristics of CIPN, pharmacogenomic studies, neurophysiological findings, treatment and outcome, and neuroprotective strategies.