Abstract 3279: Circulating inflammatory biomarker C-reactive protein and radiotherapy-related pain in breast cancer patients

Abstract

Abstract Background: Breast cancer is the most frequently diagnosed cancer and the second leading cause of cancer death in American women. Post-surgery adjuvant radiotherapy (RT) significantly improves clinical outcomes. However, many patients develop treatment-related pain that negatively impacts quality of life. Methods: We evaluated an inflammatory biomarker, C-reactive protein (CRP) in RT-associated pain in a prospective study of 366 breast cancer patients (64% Hispanic whites, 20% African Americans, 16% non-Hispanic whites) undergoing RT. In each patient, we measured pre- and post-RT plasma CRP levels using a highly-sensitive ELISA kit. Pain score was assessed at pre- and post-RT as the mean of four pain severity items (i.e., pain at its worst, least, average, and now) from the Brief Pain Inventory. Pain scores of 4-10 were considered clinically-relevant pain. Association between pain and CRP levels was evaluated using logistic regression models after adjusting for potential confounders. Results: Overall, 16% patients at pre-RT and 31% patients at post-RT had pain. In multivariable analyses, RT-related pain score change >4 was significantly associated with CRP change >1 mg/L (OR=3.24, 95%CI=1.33, 7.88), age <50 (OR=3.27, 95%CI=1.20, 8.92), and 3+ comorbidity conditions (OR=5.91, 95%CI=1.33, 26.82). Conclusion: This is the first study to suggest that increased inflammatory biomarker, CRP level was associated with RT-related pain. Impact: Future larger studies are warranted to validate our findings and facilitate the discovery and development of anti-inflammatory agents to protect patients from RT-related pain and improve quality of life in breast cancer patients undergoing RT. Citation Format: Eunkyung Lee, Omar L. Nelson, Carolina Puyana, Cristiane Takita, Jean L. Wright, Wei Zhao, Isildinha M. Reis, Rick Lin, Jennifer J. Hu. Circulating inflammatory biomarker C-reactive protein and radiotherapy-related pain in breast cancer patients [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2017; 2017 Apr 1-5; Washington, DC. Philadelphia (PA): AACR; Cancer Res 2017;77(13 Suppl):Abstract nr 3279. doi:10.1158/1538-7445.AM2017-3279