Molecular classification of breast cancer

Breast cancer is a common female tumor. With the application of molecular biology technology and the continuous improvement of medical level, great progress has been made in the treatment of breast cancer. The classification of breast cancer helps to correctly diagnose breast cancer and guide the selection of treatment methods and the prognosis of the disease. In the "St. Gallen Consensus" published in the "Annals of Oncology", the expert group divided breast cancer into four subtypes: Luminal A, Luminal B, H, and triple-negative.

1) Luminal A type: Luminal A breast cancer is sensitive to endocrine therapy but insensitive to chemotherapy. Generally, targeted therapy is not required. It is estrogen receptor (ER) and/or progesterone receptor (PR) positive, with Ki67 <14%, and human epidermal growth factor receptor (HER2) negative.

2) Luminal B type: Luminal B breast cancer is more responsive to chemotherapy than Luminal A type, but relatively less sensitive to endocrine therapy. Patients with HER2-positive disease should also consider anti-HER2 targeted therapy, ER and/or PR-positive disease, and Ki67>14% or HER2-positive disease.

3) Type H: Patients with type H breast cancer have negative ER and PR and positive HER2 expression, and generally need to consider chemotherapy and targeted therapy.

4) Triple negative: Patients with triple negative breast cancer have negative ER, PR and HER2 expressions. For such patients, chemotherapy is the only effective systemic treatment.

Tips:Ki67

Ki67 is a nuclear antigen associated with proliferating cells. Its function is closely related to mitosis and is indispensable in cell proliferation, but its exact mechanism is still unclear. Ki67 is often used as an antigen to mark the state of cell proliferation. A positive result indicates that cancer cells are actively proliferating.