ABSTRACT
To evaluate the relationship between p27Kip1 low expression in breast cancer and its prognostic implication in breast carcinoma patients. Methods All data that were associated with the study of the relationship between p27Kip1 and the prognosis for breast cancer was pooled from Cochrane library, PubMed, Embase and Medlinebase. The outcome was measured using the risk ratio (RR). Data pooling was performed by RevMan 4. 2. Results 6457 patients from 20 studies were included in this meta-analysis. RR estimate of overall survival (OS) for patients with low level p27Kip1 was 2.07 [1.66,2.60] (P<0.01). For disease free survival (DFS), the pooled RR was 1.27 [1.10,1.47] (P<0.05). The combined RR estimate of relapse free survival (RFS) for patients with low level of p27Kip1 was 1.49 [0.92, 2.42] (P >0.05). In patients with lymph node negative breast carcinoma, the combined RR for OS and RFS were 1.98 [1.34,2.91] (P <0.01) and 1.28 [0.45,3.65] (P > 0.05), respectively. Among the patients with lymph node positive breast carcinoma, the combined RR for OS and RFS was 1.92 [1.31, 2.82] (P=0.0009) and 1.35 [0.96,1.89] (P>0.05) respectively. Conclusions Low level of p27Kip1 appears to be an independent prognostic factor to OS and DFS of breast cancer patients but not to RFS. Additional studies with large patient number and widely accepted practical methods are required to derive the precise prognostic significance of p27Kip1 expression in breast cancer patients.