Pregnancy is an important and special period in a woman’s life. When they know that a little life is being conceived in their bodies, expectant mothers will be very happy and eagerly look forward to the arrival of the little life. But if breast tumors are found just at this time, it will certainly make expectant mothers anxious. At present, the incidence of breast cancer has ranked first among female malignant tumors in China, known as the “pink killer”, which is one of the most common malignant tumors during pregnancy. With the increase of women’s reproductive age and the implementation of “two-child policy” and “three-child policy”, the morbidity age of breast cancer tends to be younger, and breast cancer during pregnancy is not uncommon in clinic. Because it occurs in the special physiological period of women, it is difficult and controversial to treat it because of the need to take into account the efficacy of the mother and the safety of the unborn baby. It is hoped that by introducing relevant medical knowledge, expectant mothers can improve their awareness of breast health and be alert to and away from breast cancer during pregnancy.
First, what is breast cancer during pregnancy? （Breast Cancer in Pregnancy，BCP）
Breast cancer
during pregnancy and breast cancer during lactation refer to primary breast cancer occurring during pregnancy or one year after delivery or during lactation, collectively referred to as pregnancy-related breast cancer (Pregnancy-Associated Breast Cancer, PABC). Breast cancer during pregnancy and lactation have different biological characteristics and prognosis, and the focus of diagnosis and treatment is also different. This article focuses on breast cancer during pregnancy.
2. What examinations should be carried out when breast lumps are found during pregnancy?
Breast ultrasound should be the first choice for breast examination
during pregnancy. Breast ultrasound can assess the condition of breast and axillary lymph nodes in pregnant women. BI-RADS classification was performed according to the size, shape, and blood flow signal of the mass. Ultrasound is radiation-free, repeatable, and ultrasound-guided hollow needle biopsy of breast masses is feasible to confirm the diagnosis. As for molybdenum target examination during pregnancy. Most expectant mothers have concerns about molybdenum target examination, believing that mammography (molybdenum target) has radiation and is not suitable for breast examination during pregnancy. In fact, the radiation dose of mammography is about 3 mGy, and the estimated radiation dose to the uterus and fetus is less than 0.03 μGy, which is far below the fetal teratogenic radiation exposure threshold of 50-100 mGy, and abdominal shielding can further reduce the fetal radiation exposure dose. However, due to the dense mammary gland during pregnancy, the sensitivity of X-ray for lesion evaluation may be affected, and its clinical value is not supported by high-level evidence, so it is not recommended as the first choice. Breast magnetic resonance imaging (MRI) is of low value in the diagnosis of diseases, while gadolinium contrast agents of enhanced MRI can pass through the blood-placental barrier and may have teratogenic effects on the fetus, so breast enhanced MRI is forbidden during pregnancy. Core needle biopsy is recommended to confirm the histopathological diagnosis of breast masses during pregnancy if the imaging evaluation (BI-RADS score) of breast lesions is category 4, 5, or 3 with risk factors. CT scan, whole body bone scan and PET-CT nuclear medicine examination are strictly prohibited during pregnancy.
3. How to deal with breast cancer during pregnancy?
The treatment decision-making of breast cancer
during pregnancy is complex, and it needs to take into account the safety of both mother and fetus, so it needs multidisciplinary doctors to participate in collaborative diagnosis and treatment. At the same time, we should also fully communicate with patients and their families. The treatment of breast cancer during pregnancy does have certain risks, and both surgery and chemotherapy may have certain effects on the fetus. However, termination of pregnancy can not improve the prognosis of patients with breast cancer in the second and third trimester of pregnancy, and it is suggested that appropriate breast cancer treatment should be carried out according to the patient’s condition. According to the Chinese Clinical Practice Guidelines for Breast Cancer in Pregnancy and Lactation (2022 Edition). It is suggested that in the treatment of breast cancer in pregnancy, the multidisciplinary case management should be carried out with the leading role of breast department, the close cooperation of obstetricians and the participation of relevant departments.When the necessity of obstetrical treatment for pregnant women or fetuses is higher than that of breast cancer treatment, the obstetrics-led management mode should be adopted.
4. Can pregnant breast cancer patients be operated on?
Breast cancer surgery can be performed
during pregnancy, but early pregnancy (gestational age ≤ 13 + 6 weeks) increases the risk of abortion. Therefore, the timing of surgery is recommended in the middle and late stages of pregnancy. Modified radical mastectomy and breast-conserving surgery for breast cancer can be chosen. Modified radical mastectomy is the standard surgical procedure for patients with breast cancer during pregnancy. Because radiotherapy is not recommended for patients at all stages of pregnancy, if breast-conserving surgery for breast cancer is chosen, the timing of postoperative radiotherapy should be fully considered before operation. Is sentinel lymph node biopsy an option? Tracers are required during sentinel lymph node biopsy, and 99mTc-labeled sulfur colloids are relatively safe for developing fetuses, but the level of evidence in this study is not high. Dye tracers such as indocyanine green, isosulfan blue, and methylene blue may cause maternal anaphylaxis, and their safety in pregnant women has not been established. Therefore, the choice of sentinel lymph node biopsy during pregnancy should be cautious. No matter which surgical method is chosen, general anesthesia should be performed during the operation. General anesthesia is safe during pregnancy. 5. Can pregnant breast cancer patients undergo chemotherapy when the postoperative pathological report evaluates the condition and requires chemotherapy? Chemotherapy is an important part of the comprehensive treatment of breast cancer. Chemotherapy has corresponding side effects, and chemotherapy during pregnancy is more complex, which may lead to gestational hypertension, intrauterine growth retardation, birth weight loss and premature delivery. Chemotherapy in the first trimester of pregnancy is especially likely to lead to premature delivery and malformation of the fetus. Pregnant breast cancer patients who must receive chemotherapy should be treated in the second and third trimesters of pregnancy (≥ 13 weeks of pregnancy). However, because chemotherapy can easily induce bone marrow suppression, which may increase the risk of infection and bleeding in mothers and newborns after delivery, chemotherapy should be suspended after 35 weeks of pregnancy or within 3 weeks before planned delivery to prepare for delivery. Chemotherapeutic drugs commonly used in breast cancer include anthracyclines and taxanes. Studies have shown that the use of doxorubicin at a dose of < 70 mg/m2 in the second and third trimesters of pregnancy has a low risk of fetal malformation, death and spontaneous abortion, and has little impact on child development. Therefore, anthracycline-based chemotherapy should be used cautiously in patients with breast cancer during pregnancy. The safety of chemotherapy with taxanes during pregnancy is unknown and should be carefully selected.
6. What treatments can’t be done for breast cancer patients during pregnancy? Radiotherapy is not recommended at all stages of pregnancy, because radiotherapy during pregnancy may lead to intrauterine growth restriction, nervous system retardation, increased risk of fetal cancer, and even fetal death. Patients who need radiotherapy can do it after giving birth to a baby. Targeted drug trastuzumab and endocrine therapy drug tamoxifen can cause abortion and affect fetal development, so they are not recommended at all stages of pregnancy. Te
Do not remind women of childbearing age, especially those at high risk of breast cancer, to pay attention to breast examination before pregnancy. Do not forget to check the breast during routine physical examination during pregnancy. Breast ultrasound can be chosen for breast examination during pregnancy. If suspicious breast masses are found during pregnancy and malignancy cannot be excluded, puncture biopsy is recommended to make a definite diagnosis.
Breast cancer
