Hu JJ, et al. - Researchers examined high-sensitivity C-reactive protein (hsCRP) as an inflammatory biomarker in radiotherapy (RT)-induced skin toxicities in breast cancer. This is the first large prospective study addressing this topic. They found a significantly higher risk of grade 4+ skin toxicity in nonobese patients with elevated RT-related change in hsCRP levels. The outcomes may help to predict RT responses and guide decision making.

Methods

• Between 2011 and 2013, researchers prospectively assessed skin toxicities in 1,000 patients with breast cancer who underwent RT, via the National Cancer Institute–funded Wake Forest University Community Clinical Oncology Program Research Base.
• They assessed RT-induced skin toxicities, using pre- and post-RT plasma hsCRP levels and Oncology Nursing Society skin toxicity criteria (0 to 6).
• They determined the links between hsCRP and RT-induced skin toxicities by applying multivariable logistic regression analyses after adjusting for potential confounders.

Results

• A total of 623 white, 280 African American, 64 Asian/Pacific Islander, and 33 other race patients were included; 24% of the patients were Hispanic, and 47% were obese.
• RT-induced grade 3+ and 4+ skin toxicities were detected in nearly 42% and 15% of patients, respectively.
• Findings revealed significantly varied hsCRP levels by race and body mass index, but not by ethnicity.
• In multivariable analysis, grade 4+ skin toxicity was found to be significantly related to obesity (odds ratio [OR], 2.17; 95% CI, 1.41 to 3.34], post-RT hsCRP ≥ 4.11 mg/L (OR, 1.61; 95% CI, 1.07 to 2.44), and both factors combined (OR, 3.65; 95% CI, 2.18 to 6.14).
• Nonobese patients had a significant association of above-median post-RT hsCRP (OR, 1.93; 95% CI, 1.03 to 3.63), and change in hsCRP (OR, 2.80; 95% CI, 1.42 to 5.54) with grade 4+ skin toxicity.