Abstract | BACKGROUND: Molecular classification of breast cancer is an important prognostic factor. The distribution of molecular subtypes of breast cancer and their prognostic value has not been well documented in Asians. METHODS: A total of 2,791 breast cancer patients recruited for a population-based cohort study were evaluated for molecular subtypes of breast cancer by immunohistochemical assays. Data on clinicopathological characteristics were confirmed by centralized pathology review. The average follow-up of the patients was 53.4 months. Overall and disease-free survival by molecular subtypes of breast cancer were evaluated. RESULTS: The prevalence of the luminal A, luminal B, human epidermal growth factor receptor 2 (HER2), and triple-negative subtypes were 48.6%, 16.7%, 13.7%, and 12.9%, respectively. The luminal A subtype was more likely to be diagnosed in older women (P = 0.03) and had a stronger correlation with favorable clinicopathological factors (smaller tumor size, lower histologic grade, and earlier TNM stage) than the triple-negative or HER2 subtypes. Women with triple-negative breast cancer had a higher frequency of family history of breast cancer than women with other subtypes (P = 0.048). The 5-year overall/disease-free survival percentages for the luminal A, luminal B, HER2, and triple-negative subtypes were 92.9%/88.6%, 88.6%/85.1%, 83.2%/79.1%, and 80.7%/76.0%, respectively. A similar pattern was observed in multivariate analyses. Immunotherapy was associated with improved overall and disease-free survival for luminal A breast cancer, but reduced disease-free survival (HR = 2.21, 95% CI, 1.09-4.48) for the HER2 subtype of breast cancer. CONCLUSIONS: The triple-negative and HER2 subtypes were associated with poorer outcomes compared with the luminal A subtype among these Chinese women. The HER2 subtype was more prevalent in this Chinese population compared with Western populations, suggesting the importance of standardized HER2 detection and anti-HER2 therapy to potentially benefit a high proportion of breast cancer patients in China.
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Authors | Yinghao Su, Ying Zheng, Wei Zheng, Kai Gu, Zhi Chen, Guoliang Li, Qiuyin Cai, Wei Lu, Xiao Ou Shu |
Journal | BMC cancer
(BMC Cancer)
Vol. 11
Pg. 292
(Jul 12 2011)
ISSN: 1471-2407 [Electronic] England |
PMID | 21749714
(Publication Type: Journal Article, Research Support, N.I.H., Extramural, Research Support, U.S. Gov't, Non-P.H.S., Research Support, U.S. Gov't, P.H.S.)
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Chemical References |
- Receptors, Estrogen
- Receptors, Progesterone
- Receptor, ErbB-2
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Topics |
- Adult
- Age Distribution
- Aged
- Asian People
- Breast Neoplasms
(classification, ethnology, metabolism)
- China
- Cohort Studies
- Disease-Free Survival
- Female
- Humans
- Immunohistochemistry
(statistics & numerical data)
- Middle Aged
- Multivariate Analysis
- Predictive Value of Tests
- Prognosis
- Proportional Hazards Models
- Receptor, ErbB-2
(metabolism)
- Receptors, Estrogen
(metabolism)
- Receptors, Progesterone
(metabolism)
- Tissue Array Analysis
(statistics & numerical data)
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