Changes in plasma IL-1, TNF- and IL-4 levels are involved in chemotherapy-related cognitive impairment in early-stage breast cancer patients

To investigate changes in cytokine (IL-1 beta, TNF-alpha and IL-4) levels before and after chemotherapy and their correlation with cognitive impairment in early-stage breast cancer (BC) patients, the 190 BC patients enrolled in this study were divided into two groups: a before chemotherapy group (BCG) and an after chemotherapy group (ACG). The BCG was also divided into two subgroups according to the cognitive assessment results: one group with normal cognition (CNG) and one group with impaired cognition (CIG). Plasma cytokine levels (IL-1 beta, TNF-alpha, and IL-4) were evaluated in all patients. The mini-mental state examination (MMSE), prospective and retrospective memory questionnaire (PRMQ), and functional assessment of cancer therapy-cognitive function version 3 (FACT-Cog, version 3) were used to evaluate patients' self-perceived cognitive impairments. Furthermore, their quality of life (QOL) was evaluated. Plasma IL-1 beta, TNF-alpha and IL-4 levels were higher in the ACG than in the BCG (Z = -3.089, -2.458 and -1.987; P = 0.002, 0.014, and 0.047; respectively). Moreover, plasma IL-1 beta, TNF-alpha and IL-4 levels were higher in the CIG than in the CNG (Z = -4.353, -3.383 and -2.522; P = 0.000, 0.001 and 0.012; respectively). Furthermore, a correlation was noted between cognition (MMSE, retrospective memory (RM), prospective memory (PM), and FACT-Cog scores) and QOL in BC patients (r = -0.790, 0.852, 0.847 and 0.937, respectively), and a correlation was observed between cognition and cytokine levels (IL-1 beta, TNF-alpha, and IL-4) in BC patients (r = -0.681, -0.572 and -0.626; respectively). The present results indicated that changes in cytokine levels may occur in BC patients with chemotherapyrelated cognitive impairment (CRCI). We also found that CRCI was associated with QOL after chemotherapy in BC patients. This study provides a theoretical basis for the improvement of QOL in BC patients.