Associations between apparent diffusion coefficient (ADC) and KI 67 in different tumors: a meta-analysis. Part 2: ADC(min)

The purpose of this part of the meta-analysis was to summarize data regarding associations between minimum apparent diffusion coefficient (ADC(min)) and KI 67 in different tumors. MEDLINE library was screened for associations between ADC(min) and KI 67 in different tumors up to April 2017. Overall, 23 studies with 944 patients were identified. Associations between ADC and KI 67 were analyzed by Spearman's correlation coefficient. The pooled correlation coefficient between ADC(min) and KI 67 for all included tumors was ρ = -0.47. In detail, the correlation coefficients for separate tumors were as follows: cerebral lymphoma: ρ = –0.61 (95% CI = [–0.82; –0.41]); cervical cancer: ρ = –0.56 (95% CI = [–0.68;–0.43]); pituitary adenoma: ρ = –0.55 (95% CI = [–1.31; 0.22]); glioma: ρ = –0.40 (95% CI = [–0.55; –0.24]); breast cancer: ρ = –0.37 (95% CI = [–0.74; –0.01]); meningioma, ρ = –0.15 (95% CI = [–0.38; 0.07]).