Abstract：Abstract: Objective To investigate clinical features and prognosis of breast cancer patients with type-2 diabetes mellitus in
mainland China. Methods A systematic search of Cochrane library, Pubmed, EMBASE, CNKI, Wanfang and VIP from 2000 to 2014
was conducted. Case control studies combined with clinical features and prognosis of breast cancer patients with type 2 diabetes
mellitus in mainland China were collected. RevMan 5.2 was used to synthesize literature data. Fixed-effect or random effects model
was adopted according to heterogeneity. Results 14 studies met the inclusion criteria, including 3711 cases of patients (study group
1106 cases, 2605 cases in the control group). Diabetes was positively associated with later clinical stage (III-IV) and T stage (T3-
T
4), higher recurrence rate and mortality rate 1.77 (95%CI=1.37-2.3, P<0.0001), 1.57 (95%CI=1.19-2.08, P=0.001), 1.93 (95%
CI=1.56-2.39, P<0.00001), 1.64 (95%CI=1.18-2.28, P=0.03). The mean difference (mean difference, MD) for average age was
3.47 (95%CI=2.64-4.29, P=0.001) between the two groups. There were no statistical differences between other clinical features.
Conclusions Our findings strongly support a relationship between diabetes and older age, later clinical stage and T stage, higher
recurrence and mortality rate, and worse prognosis in breast cancer patients.
2015, Vol. 2 
