CXCR4 and neoplasm: There was no association of CXCR4 expression with tumor stage (OR 1.32, 95% CI 0.65–2.68, P = 0.438, I2 = 0) or distant metastasis (OR 1.93, 95% CI 0.56–6.72, P = 0.301, I2 = 61.4) in the non-Asian group.