Abstract:

Objective

To investigate the clinicopathological characteristics of ER(-)/PR(+) breast cancer and patients'prognosis.

Methods

We retrospectively analyzed the clinicopathological data of 762 breast cancer patients in the Affiliated Cancer Hospital of Zhengzhou University between January 2005 and December 2008. According to their ER and PR status, they were divided into three groups: ER(-)/PR(+) group (n=179), ER(-)/PR(-) group (n = 300), and ER(+)/PR(+) group (n = 283). Clinicopathological parameters including age, menstruation, tumor size, histological grade, lymphatic or vascular invasion, lymph node status, HER-2 status and histological grade were evaluated. The numeration data including age,menstruation, lymphatic or vascular invasion, HER-2 status and histological type were compared among groups using χ² test, Pairwise comparison was conducted using χ² segmentation. The ranked data including tumor size and histological grade were compared using Kruskal-Wallis H test. Kaplan-Meier method was used for survival analysis and log-rank test was used for group comparison.

Results

The proportion of the patients＜50 years was 56.4%(101/179)in ER(-)/PR(+) group, 62.7%(188/300)in ER(-)/PR(-)group and 35.0%(99/283)in ER(+)/PR(+) group, indicating a significant difference (χ²=47.497, P＜0.001). The onset age in ER(-)/PR(+) group were significantly younger than that in ER(+)/PR(+) group (χ²=20.535,P＜0.017) while there was no significant difference between ER(-)/PR(-) group and ER(-)/PR(+)group(χ²=1.825,P＞0.017). There was a significant difference in histological grade among three groups(χ² =30.362,P＜0.001). ER(-)/PR(+) group had a higher histological grade compared with ER(+)/PR(+)group (P=0.017) while no significant difference was found between ER(-)/PR(+) group and ER(-)/PR(-)group (P=0.126).There was a significant difference in HER-2 expression among three groups (χ²=56.518,P＜0.001),and HER-2 positive rate in ER(-)/PR(+) group was significantly higher than that in the other two groups(χ²=6.298,51.044,both P＜0.017). The patients were followed up for median 62 months (17-94 months). The 5-year DFS was 44%,40% and 74% in ER(-)/PR(+) group, ER(-)/PR(-)group and ER(+)/PR(+) group, respectively, and the 5-year OS was 87%, 77% and 95% in ER(-)/PR(+) group,ER(-)/PR(-)group and ER(+)/PR(+) group, respectively. The 5-year DFS and OS both presented significant differences (the 5-year DFS:χ²=95.269, P＜0.001; the 5-year OS: χ²=45.768, P＜0.001). The 5-year DFS and OS in ER(-)/PR(+) group were significantly lower than those in ER(+)/PR(+) group(χ²=56.276, P＜0.001; χ² =17.454, P＜0.001), while no significant difference was noted in the 5-year DFS between ER(-)/PR(+) group and ER(-)/PR(-) group (χ²=3.010,P=0.083), and the 5-year OS in ER(-)/PR(+) group was higher than that in ER(-)/PR(-) group(χ² = 5.549, P = 0.018).

Conclusions

ER(-)/PR(+) breast cancer has young age of onset,advanced histological grade and high rate of HER-2 positive. It has clinicopathological characteristics and prognosis similar to ER(-)/PR(-) tumor,but stronger invasion and worse prognosis compared with ER(+)/PR(+) tumor, which requires further research.

Key words: Breast neoplasms, Receptors, estrogen, Receptors, progesterone, Immunohistochemistry