An increase of serum levels of NGF was observed in patients receiving PT and TX compounds developing painful CIPN one month after finishing chemotherapy.

Chemotherapy-induced peripheral neuropathy (CIPN) is clinically introduced as loss of motor, sensory or autonomic functions due to chemotherapy. One of the significant symptoms among these patients arise is neuropathic pain which can be evaluated with the help of serum markers like Nerve growth factor (NGF).  NGF is trophic to small sensory fibers and manages nociception as well.

Velasco R and colleagues conducted a single-center prospective observational study to evaluate changes in intraepidermal nerve fiber density (IEFND) in skin biopsies and NGF levels of patients having cancer and receiving neurotoxic chemotherapy. The CIPN was ranked through nerve conduction studies, National Common Institute-Common Toxicity Criteria for Adverse Events scale and Total Neuropathy Score©, The European Organization for Research and CIPN20 questionnaire were used to define levels of neuropathic pain. Patients taken for studies were assessed both before and after chemotherapy delivery. A total of 13 patients out of 60 with neuropathic pain with burning pain in the hands (n=9) and the feet (n=12). The neuropathic pain is considerably related to the change of NGF. The patients with painless or no CIPN exhibited lower NGF (2.5±1.4 pg/mL) than patients having painful CIPN (8.7±11.9 pg/mL) after the treatment (P=0.016). On the other side, patients with painless or no CIPN exhibited significant loss of IEFND (8.37±4.82) as compared to patients (6.16±3.86) with painful CIPN (P=0.12). No association between NGF and IEFND was noticed. The study reflects that the patients receiving platinum or taxane and having painful CIPN have increase NGF rates. This result might become a possible biomarker of the neuropathic pain existence and severeness.

Further Long-term comprehensive studies are required to identify NGF relation with neurological outcomes to propose new modalities for neuropathic pain due to CIPN.