Ki 67 Expression as a Factor Predicting Recurrence of Ductal Carcinoma In Situ of the Breast: A Systematic Review and Meta Analysis
Background: Ki 67 is a marker of proliferating cells; in this meta analysis we aimed to examine whether Ki 67 expression can predict recurrence rates of breast ductal carcinoma in situ (DCIS) Materials and Methods: This systematic review and meta analysis was performed according to the Preferred Reporting Items for Systematic Reviews and Meta Analyses guidelines. Eligible articles were sought in MEDLINE up to April 30, 2017. Random effects (DerSimonian Laird) models were used for the calculation of pooled relative risk (RR) estimates; meta regression analysis was also performed. Separate analyses were performed according to Ki 67 expression cutoff levels, invasiveness of recurrence, and adjustment of studies. Results: Ten eligible cohort studies were synthesized; a significant association between Ki 67 expression and DCIS recurrence was noted for the Ki 67 cutoff at 10% (RR 1.66; 95% confidence interval [CI] 1.14 2.42) as well as the Ki 67 cutoff at 14% (RR 1.67; 95% CI, 1.01 2.77) Subanalysis on unadjusted (RR 1.48; 95% CI, 1.06 2.07) and adjusted studies (RR 2.19; 95% CI, 1.42 3.38) replicated the statistically significant findings. Ki 67 expression predicted the risk of invasive (RR 1.53; 95% CI, 1.14 2.06) and noninvasive (RR 1.59; 95% CI, 1.19 2.13) recurrence. Conclusion: This meta analysis highlights Ki 67 expression as a predictor of DCIS recurrence; nevertheless, additional adjusted studies, with adequate follow up periods, stemming from various world regions seem to be needed on this topic.
Clinical breast cancer