New advances in chemotherapy for breast cancer
Breast cancer is the most common malignant tumor in women, and the incidence of breast cancer is increasing year by year worldwide. Epidemiological data in the United States show that the mortality rate of breast cancer is declining year by year. This is closely related to the strengthening of censuses, the significant increase in the detection rate of early breast cancer and the systematic adjuvant treatment.
More than forty years ago, R et al. proposed that breast cancer is a systemic disease. Research shows that about % to % of breast cancer patients are found to have metastatic lesions when they seek medical treatment. Breast cancer may have systemic micrometastasis in its early stages, and most patients require systemic medical treatment. Currently, this treatment model has been widely accepted, and breast-conserving surgery plus adjuvant systemic therapy has been widely used in early-stage breast cancer.
The development of clinical chemotherapy regimens for breast cancer has gone through the process of single-agent chemotherapy and combination chemotherapy. First-line treatment drugs include cyclophosphamide (-), -fluorouracil (-), methotrexate, etc., and in the 1980s, anthracyclines (doxorubicin, and epirubicin) were used. The use of paclitaxel drugs (Taxol, Taxotere) in the 1990s has significantly improved the prognosis of breast cancer. Some recently developed new anti-tumor drugs, including gemcitabine (Gemzar,) and capecitabine (Xeloda,), have provided effective remedial treatments for patients with advanced breast cancer.
Commonly used chemotherapy drugs are:,,-,,-,,,,b, etc.
1. Adjuvant chemotherapy
Systemic adjuvant therapy has been widely accepted, because most people believe that reducing tumor burden is helpful to improve the efficacy of anti-tumor treatment. Most studies have proven this idea. Adjuvant chemotherapy can effectively reduce the recurrence rate and mortality of early-stage patients. Therefore, adjuvant chemotherapy has become an important part of the comprehensive treatment of breast cancer.
2. Postoperative adjuvant chemotherapy
Postoperative adjuvant chemotherapy can reduce the recurrence rate and mortality of breast cancer patients. Patients above stage 1 should receive adjuvant chemotherapy. It was once thought that patients with breast cancer with negative axillary lymph nodes and smaller than the primary tumor did not need adjuvant chemotherapy. However, about % of patients with negative axillary lymph nodes will develop recurrence or metastasis in the future. Therefore, it is now considered that even early-stage patients can receive adjuvant chemotherapy. Chemotherapy. For primary tumors& that are simultaneously node negative, adjuvant chemotherapy should be individualized. For some breast cancers with small tumors, negative lymph nodes, and good histological types, retrospective studies have shown that local treatment can achieve long-term survival and therefore do not require chemotherapy. However, people at high risk of recurrence should receive adjuvant chemotherapy even if their axillary lymph nodes are negative. High-risk groups include those who are estrogen receptor (R) negative, those who developed breast cancer during lactation or pregnancy, those with obvious familial tendencies, those with tumor thrombus formation or nerve involvement in blood vessels or lymphatic vessels in pathology reports, and/or those under the age of 10 . In recent years, with the development of genetic testing, the expression status of some genes has also become an indicator of risk, such as -B,,,, etc.
Timing of adjuvant chemotherapy: Chemotherapy should be started as early as possible after surgery. The main purpose is to effectively control or eliminate micrometastases. However, the optimal time for postoperative chemotherapy cannot be unified. The time to start postoperative chemotherapy may be affected by factors such as the patient's general recovery, the histological type of the lesion, and other factors. Some experts believe that adjuvant chemotherapy should be started within 1 week after surgery. A retrospective analysis of breast cancer patients who underwent postoperative adjuvant chemotherapy showed that there was no meaningful difference in whether chemotherapy was started sooner or later within a week. However, if adjuvant chemotherapy was started more than a week after surgery, the local recurrence rate was high and the overall survival rate was poor. Therefore, it is considered that chemotherapy should be started within a few weeks after surgery. The treatment cycle is generally periodic. Increasing the chemotherapy cycle does not improve the therapeutic effect, but will increase the toxicity of chemotherapy.
The main chemotherapy regimens include ( + + -), ( + + -), (+-+-), (+ -), -, - (dose density method), etc.
3. Neoadjuvant Chemotherapy
The significance of neoadjuvant chemotherapy is to shrink the primary tumor, increase the success rate of breast-conserving surgery, reduce the number of positive axillary lymph nodes, inhibit the activity of tumor cells, and reduce distant metastasis. The tumor's sensitivity to drugs can also be discovered. There are many studies available on neoadjuvant chemotherapy regimens. Any regimen available for postoperative adjuvant chemotherapy can be used for neoadjuvant chemotherapy.
In 2016, Bzr reported a study on neoadjuvant chemotherapy and endocrine therapy combined with chemotherapy using paclitaxel once a week, followed by fluorouracil + epirubicin + cyclophosphamide for 1 cycle. The study is confirmed before it is completed. Endocrine plus chemotherapy regimen, therefore the trial of chemotherapy alone as neoadjuvant therapy was terminated. They believe that for r/positive patients, endocrine drugs should be added to neoadjuvant therapy.
et al. comparatively studied the efficacy of (doxorubicin and cyclophosphamide) and (doxorubicin and docetaxel) regimens as neoadjuvant chemotherapy for breast cancer with large primary lesions or inoperable tumors. There were no meaningful differences in clinical effectiveness, pathological complete response rate, breast conservation rate and post-operative lymph node negative rate. Recommended reading: What should be paid attention to in breast cancer chemotherapy
etc. studied the efficacy of different cycles of doxorubicin plus docetaxel as neoadjuvant chemotherapy for operable breast cancer. Comparing consecutive cycles with consecutive cycles, the latter was better than the former in terms of pathological complete response rate and postoperative lymph node negative rate, and there was no difference in breast conservation rate.
Through the above introduction, we have realized that chemotherapy plays a very important role in the treatment of breast cancer patients. Whether before or after surgery, breast cancer chemotherapy may be used to help patients achieve good therapeutic effects. , helping patients relieve pain and recover as soon as possible.
New advances in chemotherapy for breast cancer