How to standardize systemic treatment of breast cancer?

*For medical professionals to read and refer to these precautions, do you know all of them? The treatment of breast cancer is never based on surgery alone.
Systemic treatment is the key to prolonging the overall survival (OS) and disease-free survival (DFS) of patients
.

A few days ago, the Chinese Anti-Cancer Association Breast Cancer Professional Committee published the "Chinese Anti-Cancer Association Breast Cancer Diagnosis and Treatment Guidelines and Norms (2021 Edition)"
.

Among them, the "Guidelines for Systemic Treatment of Breast Cancer" provide a detailed description of chemotherapy, endocrine therapy, anti-HER2 therapy, and whether to choose and use intensive therapy
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In this regard, the "Medical Oncology Channel" analyzes the key contents of medical treatment
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Introduction: 1.
How to evaluate molecular classification and risk of recurrence? 2.
What are the adjuvant chemotherapy options for breast cancer? Do you know these precautions? 3.
How to choose an endocrine treatment plan? How long will it take? 4.
Trapa dual target or single target, is the anti-HER2 therapy used correctly? How to evaluate molecular typing and risk of recurrence? The systemic treatment plan for breast cancer is based on the risk of recurrence and molecular classification
.

The assessment of low-risk, intermediate-risk, and high-risk breast cancer is mainly based on whether there is lymph node metastasis, tumor size, histological grade and other clinicopathological indicators, as well as immunohistochemical indicators such as ER, PR, HER2, and Ki-67
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Among them, lymph node metastasis is a relatively important judgment point
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The molecular classification of breast cancer mainly includes Luminal A, Luminal B (HER2 negative), Luminal B (HER2 positive), HER2 positive (non-Luminal), and triple negative
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For different molecular typing, options including endocrine therapy, anti-HER2 therapy, targeting, and immunotherapy can be selected
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When specifying a treatment plan, the patient's high-risk classification and molecular classification of recurrence should be considered comprehensively
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In addition, in recent years, PARP inhibitors (PARPi) have shown excellent efficacy in patients with BRCA gene mutations.
Patients should be advised to undergo susceptibility gene testing during evaluation in order to guide follow-up medication and genetic counseling
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People who benefit from chemotherapy should also be screened
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Low-risk breast cancer patients may not undergo chemotherapy; for intermediate-risk breast cancer patients, molecular classification and TNM staging should be considered for evaluation; high-risk breast cancer patients are recommended to undergo chemotherapy
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What are the adjuvant chemotherapy options for breast cancer? Do you know these precautions? Systemic treatments after breast cancer surgery include chemotherapy, endocrine therapy, and anti-HER2 therapy
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In recent years, the discussion about "de-chemotherapy" has been in full swing, but the current status of chemotherapy in the systemic treatment of breast cancer has not changed
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Common chemotherapy regimens for breast cancer include: ①Doxorubicin/cyclophosphamide (AC) and epirubicin/cyclophosphamide (EC) regimens based on anthracyclines; ②Combination of anthracyclines and taxanes Programs, such as TAC; ③Sequential programs of anthracyclines and taxanes, such as AC→paclitaxel (1 week/time), AC→paclitaxel (3 weeks/time); ④programs without anthracyclines, such as Docetaxel/Cyclophosphamide (TC); ⑤ In the case of possible paclitaxel or docetaxel infusion reaction, consider using albumin paclitaxel instead
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Two intensive programs include: ①In triple-negative breast cancer, consider using capecitabine intensive treatment (Chinese experts believe that triple-negative breast cancer is preferably a dose density program containing taxanes and anthracyclines); ②In BRCA genes When the mutation is positive, consider using PARPi
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Do you know that there are several points to pay attention to when undergoing chemotherapy? ★ 1.
Cardiotoxic breast cancer chemotherapy drugs, such as anthracyclines, paclitaxel, cyclophosphamide, etc.
, can cause damage to heart function
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Therefore, before each chemotherapy, an electrocardiogram and left ventricular ejection fraction (LVEF) measurement should be performed to evaluate the patient's cardiac function
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Among them, special attention should be paid to patients using anthracycline chemotherapy regimens: LVEF should be assessed at least every 3 months; if patients have symptoms of cardiotoxicity, LVEF<45% or a decrease of 15% from baseline, then assessment of myocardial muscle should be considered Calcin T, if necessary, discontinue the treatment to evaluate the patient's cardiac function status
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★ 2.
Contraindications of chemotherapy ★ 3.
Dosage The first dose of chemotherapy drugs should be used in accordance with the recommended dose.
If there are special circumstances, the dose can be lowered, but it should not be less than 85% of the recommended dose
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But if the patient has an adverse reaction, how to reduce the dose? While ensuring safety, how to ensure the effectiveness of the chemotherapy regimen? According to the guidelines: If the patient has an adverse reaction, a one-time reduction of 20% can be considered, but the chemotherapy regimen is only allowed to be reduced twice
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★ 4.
Synchronous radiotherapy and chemotherapy or sequential? The guidelines recommend that adjuvant chemotherapy is generally not performed at the same time as endocrine therapy or radiotherapy.
Endocrine therapy should be performed after chemotherapy is over.
Radiotherapy and endocrine therapy can be performed simultaneously
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For patients who want to use ovarian function suppression (OFS) drugs, they should be given 1 to 2 weeks before chemotherapy, and the last dose of drugs should be given 2 weeks after the end of chemotherapy
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How to choose an endocrine treatment plan? How long will it take? For HR+ breast cancer patients, endocrine therapy can effectively prolong the patient’s OS and DFS
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It is worth noting that ER 1%~100% is called ER+, but the biological behavior of ER 1%~10% is usually similar to that of negative, and the benefit in endocrine therapy is also limited
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In the selection of endocrine therapy after breast cancer surgery, judging the patient's ovarian function status is a key step
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For premenopausal women, you can choose Tamoxifen (TAM), OFS+TAM, OFS+Aromatase Inhibitor (AI)
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Among them, OFS drugs are recommended for patients with a high risk of recurrence
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High-risk patients are recommended to use drug-based OFS for 5 years, and intermediate-risk patients can use it for 2 to 3 years
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For postmenopausal women, especially those with a high risk of recurrence, tamoxifen intolerance or contraindications, tamoxifen 20 mg/day × 5 years, AI treatment can be selected for 5 years
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For patients with ER-positive breast cancer with ≥4 positive lymph nodes, regardless of menopausal status, the standard adjuvant endocrine therapy can be considered to add CDK4/6 inhibitor Abexili for 2 years; 1 to 3 lymph nodes are positive and accompanied by G3/ T3/Ki-67 ≥ 20% ER-positive patients with at least one high-risk factor may consider using abesilit enhancement
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★ 1.
The key to review.
For patients who use tamoxifen, contraception should be paid attention to during treatment, and gynecological examination should be performed every 6 to 12 months, and endometrial thickness should be checked by B-ultrasound
.

AI and LHRHa can lead to decreased bone density or osteoporosis.
Bone density (BMD) should be checked routinely before use and evaluated every 12 months.
For patients with osteoporosis, bisphosphonate or desulumab can be used Treatment
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★ 2.
Do you extend the treatment? For HR-positive patients, although the probability of recurrence within 5 years is lower than that of HR-negative patients, the risk of long-term recurrence or a second primary breast cancer is increasing
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Many studies believe that prolonged endocrine therapy can benefit some patients
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The "Chinese Anti-Cancer Association Guidelines and Standards for the Diagnosis and Treatment of Breast Cancer" recommends extended treatment: For high-risk patients using tamoxifen, if they are still in premenopausal state after 5 years of standard treatment, some patients (without high recurrence) may consider extending Use tamoxifen endocrine therapy for up to 10 years; if you are in a postmenopausal state, use AI endocrine therapy for up to 10 years; for postmenopausal patients with stage II lymph nodes, regardless of the previous treatment plan, a 5-year AI extension treatment is recommended ; For stage III postmenopausal patients, a 5-year prolonged treatment of AI is recommended
.

Trapa dual target or single target, is the anti-HER2 therapy right? HER2-positive breast cancer patients can obtain significant survival benefits from anti-HER2 therapy
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Therefore, for patients with HER2-positive breast cancer, trastuzumab±pertuzumab adjuvant therapy is recommended for one year
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But, is it chemotherapy combined with trastuzumab, or chemotherapy combined with trama dual target? According to the lymph node metastasis and the size of the tumor, the guidelines recommend the treatment plan as follows: Before anti-HER2 treatment, a cardiac function test should be performed
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LVEF<50% before treatment is a relative contraindication for anti-HER2 therapy
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★ 1.
Cardiotoxicity should be observed for 4~8h after the first treatment
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Due to the cardiotoxicity of anti-HER2 therapy, it should be very cautious to use anthracyclines at the same time, but it can be used sequentially in the early and late stages
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It can be used concurrently with non-anthracycline chemotherapy, endocrine therapy or radiotherapy
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The assessment of changes in LVEF should be extremely cautious, and LVEF should be tested every 3 months
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If LVEF is less than 50% or lower than 16% of the baseline before treatment, treatment should be suspended until it recovers above 50% of the available drugs; if it does not recover, or if it continues to worsen or develops heart failure, trastuzumab therapy should be terminated
.