Breast cancer in young women of Chinese Han population: A retrospective study of patients under 25 years.

BACKGROUND: Breast cancer has aggressive clinical and pathological features in younger women and is characterized by poorer prognosis than in older women. However, data on women <25 years are limited.

OBJECTIVE: The aim of the present study was to evaluate the different pathological characteristics and prognostic factors in Chinese women with breast cancer <25 years at the time of diagnosis.

METHODS: This retrospective study included 94 patients (aged <25) of Chinese Han population with operable breast cancer at the National Cancer Center/Cancer Hospital, Chinese Academy of Medical Sciences between January 1, 2000 and September 30, 2015. Univariate and multivariate Cox regression analysis were performed. The median follow-up duration was 64 months (range, 11-200 months).

RESULTS: The HER2-positive and triple-negative groups had a higher T (P=0.002) and N stage than the luminal A group (P=0.014). The 5-year overall survival (OS) was 90.4%, and the disease-free survival (DFS) was 74.5%. The 5-year DFS varied among the four groups were 94.1 vs. 76.9 vs. 45.5 vs. 66.7%, respectively; P=0.009. Multivariate analysis showed that only estrogen receptor (ER) status was a significant predictor of OS and DFS [Hazard ratio (HR)=5.3, 95% confidence interval (CI)=1.11-25.27, P=0.036; HR=2.712, 95%CI=1.27-5.80, P=0.01).

CONCLUSION: HER2-positive and triple-negative breast cancer are more likely to have poor prognosis in patients<25years. Hence, ER status may be identified as an independent prognostic factor for predicting young women with breast cancer.