Purpose: The prognostic significance of the Wilms' tumor suppressor gene(WT1) mRNA expression was evaluated in patients with invasive breast cancer.
Experimental design: WT1 mRNA expression in tumor tissues (n = 99) was examined by a quantitative, real-time PCR assay.
Results: No significant association was observed between WT1 mRNA levels and clinicopathological parameters such as menopausal status, tumor size, lymph node status, histological grade, and estrogen receptor status. Five-year disease-free survival rate of patients with high WT1 mRNA levels (62.6%) was significantly (P < 0.05) poorer than those with low WT1 mRNA levels (77.2%). Lymph node metastasis (P < 0.05), high histological grade (P < 0.01), and estrogen receptor negativity (P < 0.05) were also significantly associated with poor prognosis, respectively. Multivariate analysis revealed that WT1 mRNA levels were a significant prognostic factor, independent of the other conventional prognostic factors.
Conclusions: These results suggest that measurement of WT1 mRNA levels in tumor tissues might be useful as a new prognostic factor in breast cancer patients.