Inflammation-related proteins as biomarkers of treatment-related behavioral symptoms: A longitudinal study of breast cancer patients and age-matched controls

•Breast cancer patients and controls assessed pre-treatment to 2 years post-treatment.•Measured were 7 symptoms, 4 markers including Tumor Necrosis Factor (TNF)-receptor.•After breast cancer treatment, all 4 inflammatory markers increase transiently.•Post-treatment, worsened physical functioning and pain persist through 2 years.•These worsened symptoms coincide with TNF-receptor increases, a potential candidate biomarker.