Objective To study the clinical and prognostic value of CK19 mRNA-positive circulating tumor cells in early breast cancer patients. Methods We analyzed the peripheral blood in 50 patients with early breast cancer after surgery and before the initiation of any adjuvant treatment for the presence of CK19 mRNA-positive circulating tumor cells using a nest reverse polymerase chain reaction assay. All patients were followed up. Results CK19 mRNA-positive cells were detected in 40.0 %(20/50) of patients with early breast cancer, 12.5 %(3/24) of patients with breast benign lesions, but 5 %(1/20) in healthy individuals (P =0.017,P =0.004); 11 to 20 of them relapsed during the follow-up period (P =0.002). There was no significant association between the detection of CK19 mRNA-positive cell and the patients' menstrual status, tumor stage, tumor size, etc (P ＞0.05). Detection of peripheral-blood CK19 mRNA-positive cells was associated with reduced median relapse-free interval in early breast cancer patients (P =0.007). Conclusion CK19 mRNA is one of the molecular markers for the detection of circulating tumor cells in early breast cancer. Detection of peripheral blood CK19 mRNA-positive cells might be an important predictive value as a marker of relapse in early breast cancer patients.

Objective To explore the relationship between MspⅠpolymorphism of CYP1A1 gene and susceptibility to breast cancer in Yi nationality in Yunnan province. Methods The gene polymorphism of restriction enzyme of 3′-terminal of CYP1A1 was detected by PCR-RFLP in 60 healthy Yi women , 51 Yi women with breast cancer, 235 healthy Han women, and 250 Han women with breast cancer. Results The distribution frequency of CYP1A1-MspⅠgenotypes was significantly higher in Yi women with breast cancer (51.0%) than in the healthy Yi women (33.3%) (P < 0.05), an the allele C had a higher frequency in women with breast cancer than in healthy controls (P < 0.05). Significant differences of frequencies were found in genotypes TT, TC and CC between women with breast cancer and healthy controls (P < 0.05). The risks of TC and CC for breast cancer were 1.19 and 1.95 folds respectively to TT genotype. But as compared with Yi women , the distribution frequency of CYP1A1-MspⅠ genotypes did not differ between Han women with breast cancer and in the healthy control (P > 0.05), and there were no differences in three genotype frequencies (P > 0.05). Conclusions Gene polymorphism of CYP1A1 genotypes may be associated with the risk of breast cancer in Yi nationality but not in Han nationality in Yunnan. The mutation of CYP1A1 gene may increase the incidence of breast cancer in Yi nationality.