The disease burden of breast cancer in China is growing, and its proportion contributed to the global burden is increasing accordingly. The western countries have achieved reduction of mortality and slow growth of incidence, while the breast cancer incidence and mortality rates have been increasing constantly with lower survival rates in China. The remarkable characteristics of breast cancer burden in China is the disparities of the current status and time trends of incidence, mortality and survival between urban and rural area. The breast cancer disease distributions and time trends in China and the differential from the developed countries are described, which may be benefit to draw the international experience on prevention, early detection, medical care and survival management. Assessment of the existing evidence, elaboration of the prevention, control strategies in consideration of Chinese social-economic and culture situation would be beneficial to rise to the future challenge.
Asian Continental Ancestry Group ; Breast Neoplasms ; China ; Humans ; Incidence ; Survival Rate

OBJECTIVESTo analyze the survival of breast cancer molecular subtypes and to examine the effect of therapy on the long-term prognosis of different subtypes.

METHODSThis study included 3 586 breast cancer patients with estrogen receptor (ER), progesterone receptor (PR) and human epidermal growth factor receptor-2 (HER2) information in Shanghai Breast Cancer Survival Study, a population-based prospective cohort study established in 2002. Molecular subtypes, based on immunohistochemistry were categorized as follows: Luminal A, Luminal B, HER2, and triple-negative subtype. Characteristics and clinical data were collected through questionnaires and medical records at baseline survey and sequential follow-up surveys. Survival rates of different molecular subtypes were analyzed and compared with Log-rank tests. Multiple Cox regression models were used to evaluate the effect of therapy on long-term prognosis of different molecular subtypes.

RESULTSAmong the 3 586 cases, Luminal A, Luminal B, HER2 and triple-negative breast cancer subtypes accounted for 54.5%, 16.6%, 13.9%, and 14.9%, respectively. With a median follow-up of 10.3 years (ranging 0.6 to 12.8 years), the 10-year overall survival (OS) rates for the four subtypes were 82.7% (95% CI: 80.9% to 84.4%), 77.7% (95% CI: 74.1% to 80.8%), 76.3% (95% CI: 72.3% to 79.8%), and 74.8% (95% CI: 70.9% to 78.3%), respectively. The 10-year disease to free survival (DFS) rates were 79.0% (95% CI: 76.7% to 81.0%), 76.0% (95% CI: 71.9% to 79.5%), 73.6% (95% CI: 68.9% to 77.7%), and 74.5% (95% CI: 69.4% to 78.9%), respectively. Significant difference in survival among four subtypes was observed (Log-rank test, P<0.01). Multivariate Cox regression indicated that hormonal therapy can significantly reduce the long-term risk of total mortality and recurrence breast cancer specific mortality among Luminal A subtype patients. Adjuvant chemotherapy could improve the long-term prognosis of triple-negative breast cancer. No benefit from radiotherapy was observed for four subtypes of breast cancer in terms of long-term prognosis.

CONCLUSIONSMolecular subtypes based on ER/PR/HER2 could provide important information to predict breast cancer prognosis. The hormonal status was an important basis for individualized therapy and precision medicine.

Breast Neoplasms ; Chemotherapy, Adjuvant ; Cohort Studies ; Disease-Free Survival ; Humans ; Immunohistochemistry ; Prognosis ; Proportional Hazards Models ; Prospective Studies ; Receptor, ErbB-2 ; Receptors, Estrogen ; Receptors, Progesterone ; Survival Rate ; Triple Negative Breast Neoplasms