Pre-RT pain was more prevalent in patients with AA or HW race/ethnicity, BMI ≥ 30 kg/m2, HER2-positive tumor, received trastuzumab alone or taxane+trastuzumab, received ALND, or pre-RT CRP ≥ 10 mg/L, compared to their respective comparison groups. The gene discussed is CRP; the disease is neoplasm.