Some breast cancer patients will receive some treatment before surgery, called neoadjuvant therapy, with treatments such as chemotherapy, targeted therapy, and endocrine therapy.
What does neoadjuvant therapy do?
Evidence shows that neoadjuvant therapy with the same regimen and course of treatment is as effective as adjuvant therapy and can lead to breast conservation in some patients who cannot be breast conserved and surgery in some inoperable patients, but some patients (less than 5%) may progress during neoadjuvant therapy and even lose the opportunity for surgery. After neoadjuvant treatment, if pathological complete remission (PCR) is achieved, which means that the cancer cells are found to disappear under the microscope, it is predicted that the treatment will have a better long-term outcome. Specifically for chemotherapy as a modality, in addition to the above-mentioned advantages, early chemotherapy can prevent the formation of drug resistance and can provide insight into the sensitivity of the tumor to chemotherapy in vivo.
However, neoadjuvant therapy also has some shortcomings. On the one hand, drug-induced adverse effects (e.g., chemotherapy-induced anemia, lowered white blood cells) may increase the chance of infection and prolong the duration of surgery. On the other hand, the lesions regress after neoadjuvant therapy, and pathological examination cannot determine whether the cancer is in situ or invasive, while cancer cells in the lymphatic tissue are killed, affecting the determination of clinical staging, which can have an impact on survival analysis.
Is neoadjuvant therapy available?
What is the risk of neoadjuvant therapy?
Physicians will consider neoadjuvant therapy if one of the following conditions is met:
- The tumor is large, or the tumor is large.
- Large tumor, or a slightly larger mass but the physician will evaluate other risk factors in combination;
- Metastasis in the axillary lymph nodes;
- Human epidermal growth factor receptor-2 (HER-2)-positive or triple-negative breast cancer, which is usually considered for larger tumors only;
- Human epidermal growth factor receptor-2 (HER-2)-positive or triple-negative breast cancer, which is usually considered for larger tumors;
- Wanting breast conservation, but the ratio of tumor size to breast volume is too large for breast conservation.
The following patients are not candidates for neoadjuvant therapy:
- Breast cancer without a confirmed histopathological diagnosis. Histopathologic diagnosis and immunohistochemical index results for estrogen receptor (ER), progesterone receptor (PR), HER-2, and cell proliferation index Ki-67 are currently recommended prior to treatment, and cytology is not recommended as a pathologic diagnostic criterion.
- Early pregnancy is an absolute contraindication to neoadjuvant therapy, and chemotherapy should be chosen with caution if it is post-pregnancy, although successful use has been reported abroad.
- The elderly, in poor health with severe heart and lung disease, are not expected to tolerate chemotherapy in these populations.
- Those who are unable to confirm the size of the invasive cancer or to clinically assess the efficacy.
Screening assessments are also performed before neoadjuvant therapy is identified
Tumor-related evaluation
- Physical examination of the lesion with precise measurement of the longest diameter of the primary breast lesion and axillary lymph nodes, or the sum of the longest diameter in the case of multiple masses.
- Imaging, the longest diameter of the tumor is measured by breast ultrasound, x-ray, and usually evaluated with magnetic resonance imaging (MRI).
- Histologic diagnosis of invasive carcinoma or carcinoma in situ with ipsilateral axillary lymph node metastasis is obtained along with immunohistochemistry (except in occult breast cancer) for lesions and axillary lymph node puncture biopsies of the breast.
- If it is not clear whether the enlarged lymph node is a metastasis, the physician will obtain pathologic results by aspiration.
- Markers are placed within the lesion or the skin on the surface of the tumor is marked to provide a basis for the scope of subsequent surgery.
- For those whose physical examination is considered lymph node negative, physicians usually perform an axillary anterior lymph node biopsy, which can provide additional information for subsequent surgery and systemic treatment.
Evaluation of systemic condition
- Perform routine blood work, liver and kidney function, electrocardiogram, chest radiograph, and liver ultrasound. Patients with locally advanced breast cancer or inflammatory breast cancer will also require an additional whole-body bone scan, chest CT, and usually cardiac function tests if there is a history of prior heart disease.
- Women of childbearing age are tested with a pregnancy test and contraception.
After screening and evaluation of those eligible for neoadjuvant therapy, the physician will consider starting neoadjuvant therapy, which usually includes paclitaxel and/or anthracyclines in the regimen, with the addition of targeted anti-HER-2 drugs for those who are HER-2 positive, and possibly endocrine therapy for some strong hormone receptor positives.