Chemotherapy-induced peripheral neuropathy

Chemotherapy-induced peripheral neuropathy (CIPN) is a nerve-damaging side effect of antineoplastic agents in the common cancer treatment, chemotherapy. CIPN afflicts between 30% and 40% of patients undergoing chemotherapy. Antineoplastic agents in chemotherapy are designed to eliminate rapidly dividing cancer cells, but they can also damage healthy structures, including the peripheral nervous system. CIPN involves various symptoms such as tingling, pain, and numbness in the hands and feet. These symptoms can impair activities of daily living, such as typing or dressing, reduce balance, and increase risk of falls and hospitalizations. They can also give cause to reduce or discontinue chemotherapy. Researchers have conducted clinical trials and studies to uncover the various symptoms, causes, pathogenesis, diagnoses, risk factors, and treatments of CIPN. CIPN symptoms manifest themselves as deficits in sensory, motor, and/or autonomic functions of varying intensity, and they can significantly reduce a patient's functional quality of life. Sensory symptoms affecting the hands and feet generally develop first. Sensory side effects are caused when nerves in the most distal parts of the limbs are damaged. Patients may experience numbness, tingling, altered touch sensation, gait and balance disturbances, burning pain, thermal allodynia or hyperalgesia, impaired vibration sense, extreme temperature sensitivity, paresthesia, and/or dysesthesia as part of sensory damage. On the other hand, motor symptoms are less frequently seen as sensory symptoms. Motor symptoms of CIPN can include cramping, distal weakness, difficulty handling small objects, and impaired movements. In severe cases, motor symptoms can lead to complete immobilization and severe disability. Finally, autonomic symptoms usually involve orthostatic hypotension, constipation, and altered urinary function. A patient experiencing CIPN symptoms may have difficulty performing daily functionalities like walking, dressing themselves, writing, typing, and other activities related to the hands and feet.