There are many patients who love to ask their doctors questions such as.
”Doctor, is my disease serious?”
”Doctor, is my disease early or late?”
In fact, breast cancer cannot be described only by “serious” or “early/late” stage. In the family of breast cancer, there are not only early/late stages of breast cancer, but also histological grading of pathology, and molecular typing of breast cancer. The prognosis of breast cancer often requires a combination of all this information to make a comprehensive judgment, and the treatment of breast cancer also requires a combination of all this information to make accurate decisions. So, today we will learn what is the staging, grading and staging of breast cancer.
Staging of Breast Cancer
Breast cancer staging takes into account three basic factors: tumor size, the presence of lymph node metastasis, and whether the cancer has spread to other sites. Tumor size is represented by T, lymph node status is represented by N, and whether there is distant metastasis is represented by M. The specific meanings are represented as follows.
T0: primary cancer not detected
Tis: Carcinoma in situ
T1: tumor length and diameter ≤2cm
T2: tumor length diameter >2cm, ≤5cm
T3: tumor length diameter >5cm
T4: regardless of tumor size, tumor invades chest wall or skin
N0: No enlarged lymph nodes in the ipsilateral axilla
N1: 1-3 lymph nodes metastasis in the ipsilateral axilla
N2: ≥4 lymph nodes metastasis in the ipsilateral axilla
N3: ipsilateral axilla with ≥10 lymph node metastases or ipsilateral internal breast lymph node metastases
M0: no distant metastasis
M1: with distant metastasis
The combination of the three makes up the staging of breast cancer, as follows.
Stage 0: TisN0M0
Stage I: T1N0M0
Stage IIa: T0N1M0, T1N1M0, T2N0M0
Stage IIb: T2N1M0, T3N0M0
Phase IIIa: T0N2M0, T1N2M0, T2N2M0, T3N1M0, T3N2M0
Stage IIIb: T4N0M0, T4N1M0, T4N2M0
Stage IIIC: any T, N3M0
Stage IV: any T, any N, M1
The commonly referred to early stage breast cancer refers to stage 0, stage I, stage IIa, stage IIb; stage IIIa, stage IIIb, stage IIIc are usually called locally advanced; stage IV is really advanced.
Histological grading of breast cancer
The degree of differentiation of breast cancer is closely related to the prognosis. Histological grading in pathology is assessed from three aspects: the degree of glandular duct formation, the polymorphism of the nucleus, and the nuclear division count. Specific grading criteria are as follows.
Glandular duct formation: 1) the presence of most obvious glandular ducts is scored as 1; 2) the presence of moderately differentiated glandular ducts is scored as 2; 3) the cells show solid lamellar or striated growth is scored as 3.
Nucleus polymorphism: 1) 1 point for consistent nucleus size, shape and chromatin; 2) 2 points for moderate nucleus irregularity; 3) 3 points for obvious nucleus polymorphism.
Nuclear division count: 1) 1 point for 1/10 HPF; 2) 2 points for 2-3/10 HPF; 3) 3 points for >3/10 HPF.
The scores of the three items were summed, and 3-5 were classified as grade I (well differentiated); 6-7 were classified as grade II (moderately differentiated); 8-9 were classified as grade III (poorly differentiated).
Molecular staging of breast cancer
The molecular staging of breast cancer is closely related to the risk of recurrence and metastasis, and the prognosis and treatment decisions for breast cancer vary by molecular staging. Using pathological immunohistochemical findings, breast cancers can be classified into 4 categories.
LuminalA type: ER-positive, PR-positive (>20%), HER2-negative, Ki-67 <30%. This subtype of breast cancer has a better prognosis, low recurrence rate, and is sensitive to endocrine therapy, which is the mainstay of endocrine therapy.
LuminalB type.
(1) ER positive, PR negative or low expression (<20%), HER2 negative, Ki-67 >30%. This subtype also has a better prognosis, second only to LuminalA, and treatment is based on chemotherapy combined with endocrine therapy.
2) ER positive, HER2 positive, PR and Ki-67 indicators are not limited. These patients are sensitive to both endocrine therapy and targeted therapy, and require a combination of chemotherapy + targeted therapy + endocrine therapy.
HER2 overexpression type: ER-negative, PR-negative, HER2-positive. Chemotherapy + targeted therapy is the main treatment for this group of patients.
Triple negative type: ER, PR and HER2 negative. This subtype accounts for about 20% of all breast cancers and is the type with the highest risk of recurrence and poor prognosis. Treatment is limited, with chemotherapy being the mainstay. In recent years, immunotherapy has been suggested to have some efficacy in triple negative breast cancer.
The outcome of breast cancer cannot be summarized by the phrase “serious or not”, and the stage of breast cancer alone cannot fully represent the prognosis of breast cancer. Currently, breast cancer is one of the malignant tumors with more comprehensive treatment options and better overall prognosis. The treatment of breast cancer is gradually becoming more precise, which often requires a comprehensive assessment based on the patient’s stage, molecular typing and related high-risk factors, and then a reasonable treatment decision is made. Standardized and precise individualized diagnosis and treatment is the cornerstone of improving the prognosis of breast cancer patients.