A systematic review and meta-analysis on the effects of metformin on survival outcomes and risk in women with cervical cancer

Abstract

Objective: A systematic review and meta-analysis was conducted to quantitatively assess the effects of metformin on both the treatment and risk of cervical cancer in women. Materials and Methods: A search was conducted in a number of databases including CNKI, VIP, Wanfang Digital Journal Full-text Database, PubMed, Cochrane, and Web of Science. In accordance with inclusion and exclusion criteria screening in the literature, Newcastle-Ottawa scale and RevMan 5.3 software were employed to perform the meta-analysis. Results: A total of five studies taken from four articles involving 149,742 participants were finally included in meta-analysis,two random clinical trials (RCTs) and three retrospective cohort studies. Evaluation of metformin usage in two of the studies did not show significant association with five-year overall survival (OS) of patients receiving adjuvant whole-pelvic radiation therapy (WPRT) as a primary therapy compared to those . not using metformin (RR = 1.08, 95% CI 1.00-1.18, p = 0.06). In the three other studies metformin use was associated with a significant reduction in cervical cancer risk in diabetes mellitus patients (RR = 0.60, 95% CI 0.44-0.82, p = 0.001). Conclusion: Merformin use is associated with a reduction in cervical cancer risk in patients with diabetes mellitus, but is not associated with five-year OS of patients receiving WPRT. Further studies are required to confirm survival outcomes for use of metformin in cervical cancer.