There was significant heterogeneity in the results of the intervention period subgroup analysis (91.3%, 99.5%, 98.0%, 60.7%), suggesting that the effect of exercise on IL-6, CRP, TNF-α, and IL-10 levels in breast cancer patients with different intervention periods is likely to be a source of heterogeneity in the included studies. This evidence concerns the gene CRP and breast carcinoma.