Can Breast Cancer Subtypes Determine Its Stage?
The subclassification and staging of breast cancer are two independent yet interrelated concepts. Subclassification categorizes breast cancer based on molecular pathological characteristics, while staging reflects the tumor's size, degree of spread, and overall progression within the body. Combining these two can provide crucial insights for treatment planning. Below, we explain the differences and relationships between subclassification and staging from their respective perspectives and introduce clinical management strategies for breast cancer.
Breast cancer subclassification, based on the molecular properties of tumor tissue, is a key means of assessing disease conditions and guiding personalized treatment. Common subclassification methods include: Hormone receptor-positive/HER2-negative subtypes, Luminal A and Luminal B: Often sensitive to hormone therapy with better prognosis. HER2-positive subtype: Can improve efficacy through targeted drug therapy like trastuzumab. Triple-negative breast cancer: Highly malignant but more sensitive to chemotherapy. Subclassification is determined through immunohistochemical tests for indicators such as ER, PR, HER2, closely related to the biological characteristics of the tumor within the patient.
Breast cancer staging is based on the TNM staging system: T - Tumor size: Assesses the size and invasion depth of the primary tumor, with early-stage T1 being under 2 cm. N - Lymph node status: Determines whether cancer cells have invaded lymph nodes. M - Metastasis: Whether the cancer has spread to distant organs such as bones, lungs, or liver. Staging typically ranges from 0 to IV, with I-II considered early stages, III as locally advanced, and IV indicating distant metastasis.
While subclassification and staging are independent, their combined analysis more effectively predicts breast cancer progression and prognosis: Under the same stage, different subclassifications such as Luminal A and triple-negative breast cancer may have vastly different prognoses. Some patients with low-stage I-II disease may require more aggressive treatment due to their triple-negative subclassification, while some high-stage patients may adopt hormone therapy primarily due to their Luminal A subclassification.
Pharmacological Treatment: Hormone receptor-positive types recommend endocrine therapy like tamoxifen or anastrozole; HER2-positive types suggest trastuzumab combined with chemotherapy; triple-negative breast cancer relies on conventional chemotherapy. Surgical Treatment: Early-stage patients can choose mastectomy or breast-conserving surgery, while III-IV stages may require surgery after neoadjuvant therapy. Adjuvant Radiotherapy and Chemotherapy: Post-surgery, radiotherapy can be used based on staging to control recurrence risk; chemotherapy is suitable for later stages or high-malignancy subclassifications. Although breast cancer subclassification does not directly determine staging, combining it with staging aids in developing more precise treatment plans. Breast cancer diagnosis requires professional medical guidance, with individualized treatment plans selected based on subclassification and staging to improve patient quality of life and survival rates.
