Sequential, Noninvasive, Neurosensory Monitoring During Chemotherapy: Clinical Consequences of Identifying Neuropathy

A significant proportion of patients experience symptoms of sensory nerve damage from chemotherapy known as chemotherapy-induced peripheral neuropathy (CIPN). CIPN is a major dose-limiting toxicity of many chemotherapeutic regimens. Early detection and quantification of CIPN is a significant challenge. It is hypothesized that noninvasive, nonpainful, pressure-specified sensory device (PSSD) will be a sensitive and specific tool for measuring CIPN. If CIPN can be detected early, then oncology might alter the drug regimen. Additionally, it is known that more than 33% of diabetics with neuropathy have a chronic nerve entrapment, as determined by a positive Tinel sign. If CIPN persisted after chemotherapy stopped, then presence of a peripheral nerve entrapment could be evaluated.

A prospective cohort of patients receiving chemotherapy were referred by their oncologist. During the administration of their intravenous (IV) chemotherapy, the patient had PSSD testing of the index, little finger, and finger and big toe pulp. Quality-of-life outcome instruments QLQ-CIPN20, and the Michigan Neuropathy Symptom Score Instrument were administered. Each patient was evaluated for the presence of a Tinel sign at known sites of nerve entrapment. Inclusion criteria were patients receiving neurotoxic chemotherapy (Vincristine, Taxol, or Cisplatin).

Thirteen patients were enrolled. There were no complications from neurosensory testing. The PSSD was 80% sensitive and 100% specific identifying symptomatic neuropathy, p < 0.014, chi square and p < 0.05 using the Fisher's exact test. PSSD testing became abnormal prior to the patient becoming symptomatic and prior to the presence of a positive Tinel sign.

Noninvasive and nonpainful neurosensory testing is feasible to do during chemotherapy IV infusion. This can identify changes in peripheral nerve function that correlate with a patient's symptoms and therefore might be used by the oncologist to alter the patient's chemotherapy dosage and limiting chemotherapy toxicity.