Abstract PO2-11-10: Can chemotherapy-induced peripheral neuropathy be predicted? Implications for future prevention and treatment of this side-effect
Authors: Maity Alisha , Metz Nolan , Fleck Kathryn , Ali Zonera , Shevade Aarthi , Ghaneie Arezoo , Wallon Margaretha 
Published: May 2024

Abstract
Background: The pain and sensory abnormalities associated with chemotherapy-induced peripheral neuropathy (CIPN) may persist for months or even years after chemotherapy. CIPN has a negative impact on routine activities, functions, and behaviors in the domestic, work, and social lives of cancer patients, adversely affecting the quality of their survivorship.
CIPN is a major adverse effect of taxanes and other agents, possibly requiring dose-reduction or early termination of treatment. Taxane-based regimens are first-line treatment in both early-stage and metastatic breast cancer and therefore place numerous women at risk for developing CIPN. Regrettably, taxane-induced neurotoxicity can be arduous to predict, and there are no preventive or curative treatments currently available.
Our work aims to assess a predictive tool for identification of patients at high risk of developing neuropathy and the progression of symptoms towards chronic CIPN.
We hypothesized that oxidative stress might be a triggering event for the development of CIPN and that changes in glutathione recycling can identify patients at high risk for developing prolonged and severe CIPN. This hypothesis is based on reports in the literature proposing that CIPN is triggered by damage to the myelin sheath, which protects nerves from damage, by drug-induced free radicals in and around the nerves. Damage to myelin, a lipid- and protein rich sheath, by lipid peroxidation can result in loss of signal transmission, false signaling, or signal overload. Prolonged exposure to elevated levels of free radicals might result in structural changes to the nerves.
Methods: Cancer patients seeking treatment at the Lankenau Medical Center Cancer center were asked to participate in our Institutional Review Board approved study of adverse effects. In this on-going study, the cohort (Ntotal =352) includes 104 breast cancer patients that are predominantly Caucasian with 14.9% African American. The median age is 56 (range 26 – 82) and 60.9% were treated with a taxane-based regimen. Nearly half the breast cancer group were diagnosed with Stage I disease. All consented patients donated a tube of blood prior to each treatment and filled out the Rotterdam Symptom Checklist (RSCL). Blood samples were analyzed for glutathione recycling using the ChemoTox assay (MNT™ Test, MYNARI Biomedical) and lipid peroxidation using a thiobarbituric acid reactive substances (TBARS) test (Cayman Chemical). All samples were analyzed in duplicate, and results analyzed using GraphPad Prism 8.4.3.
Results: Preliminary results from the first 83 breast cancer patients showed African American patients reported a higher rate of NCCN grade 2 and 3 CIPN while Caucasians reported a higher rate of severe, long-lasting CIPN. Our results showed that patients who reported CIPN at later cycles had diminished glutathione recycling capacity already after the first treatment. Drop in recycling capacity had an inverse relationship with lipid peroxidation and grade of CIPN. Both decreased recycling capacity and increase in lipid oxidation were apparent already after the first treatment in patients that reported CIPN after cycle 6-8 or after completion of treatment
Discussion: There are many proposed mechanisms for the development of CIPN. One mechanism that is shared by both most agents is damage induced by free radicals released following chemotherapy. We show that patients with reduced ability to neutralize free radicals have elevated and prolonged lipid peroxidation. Both processes precede the development of CIPN by several treatment cycles. Therefore, this test could identify patients that might benefit from other regimens rather than a taxane-based therapy. The test could also aid in the identification of patients for preventive therapy once such agents become available.
Citation Format: Alisha Maity, Nolan Metz, Kathryn Fleck, Zonera Ali, Aarthi Shevade, Arezoo Ghaneie, Margaretha Wallon. Can chemotherapy-induced peripheral neuropathy be predicted? Implications for future prevention and treatment of this side-effect [abstract]. In: Proceedings of the 2023 San Antonio Breast Cancer Symposium; 2023 Dec 5-9; San Antonio, TX. Philadelphia (PA): AACR; Cancer Res 2024;84(9 Suppl):Abstract nr PO2-11-10.