For premenopausal breast cancer patients, the National Comprehensive Cancer Network (NCCN) guidelines suggest that all young premenstrual patients need to be aware of the potential impact of upcoming chemotherapy on their reproductive function. Prior to treatment, patients should inform their doctors how they want to become pregnant in the future. Those who plan to become pregnant in the future should consult a reproductive specialist before becoming pregnant.
Is it possible to have children?
If fertility is indicated, there is no evidence that fertility increases the risk of breast cancer recurrence, and the NCCN guidelines recommend that patients who wish to become pregnant should consult with a fertility specialist before becoming pregnant. Even though amenorrhea usually occurs during or after chemotherapy, most patients younger than 35 years of age will resume menstruation within 2 years after completion of adjuvant chemotherapy. There is also no necessary link between menstruation and fertility.
There are limited data on fertility after chemotherapy. Some studies have not found an effect of post-treatment fertility on breast cancer survival after observation. Studies from the United States that compared mortality in patients who gave birth after breast cancer treatment with those who did not did not find that patients who gave birth had higher mortality rates. Three large clinical trials have included nearly 4,000 children born after treatment for malignancy and showed no significant increase in fetal malformations or tumor incidence compared with the general population.
What are the considerations for treatment for those with fertility needs?
Before treatment begins, physicians ask patients about their fertility wishes after treatment. Regarding chemotherapy, physicians are guided by the available evidence and try to use drugs that have little impact on reproductive function. Among the chemotherapy drugs commonly used for breast cancer, alkylating agents are generally considered to have definite ovarian toxicity, destroying follicles and leading to ovarian failure. Anthracyclines, fluorouracil, and vinorelbine have relatively little effect on female reproductive function. Tamoxifen itself does not cause infertility, but its use is also not recommended at this time because of its possible long-term teratogenic effects.
Ovarian suppression therapy is ovarian-protective and, when used concurrently with chemotherapy, reduces the risk of long-term post-chemotherapy amenorrhea in young breast cancer patients, and these patients have a higher rate of post-treatment conception. Some doctors abroad currently recommend that patients with fertility requirements have their germ cells frozen in advance of chemotherapy to preserve healthy egg cells. This is not yet recommended in China.
What time can I choose to get pregnant after treatment?
When it comes to the timing of pregnancy after treatment, doctors recommend 2 years after the end of postoperative adjuvant therapy. The 2-year postoperative period is the peak of recurrence and is not a good time to have children because of the adjuvant chemotherapy and radiation therapy. One study found a correlation between pregnancy and improved overall survival in women at least 24 months after diagnosis. After 2 years of adjuvant therapy, if there is no sign of recurrence, then fertility can be considered.
However, if the patient herself has advanced breast cancer, because there may be residual tumor cells, hormonal changes during pregnancy may reactivate the residual tumor cells and accelerate disease recurrence, so it is recommended that such patients who have a strong desire to have children should extend the option of pregnancy until 5 years after the end of postoperative adjuvant therapy.
Additionally, contraceptive options for patients with breast cancer without fertility requirements include intrauterine devices, sterilization, and vasectomy or vasectomy for the partner, but, given the hormone-dependent nature of breast cancer, contraceptive medications are contraindicated.
Is it possible to breastfeed?
On the issue of breastfeeding after childbirth in breast cancer patients, the NCCN guidelines state that breastfeeding after childbirth is not contraindicated in breast cancer patients who have undergone breast-conserving surgery. However, breast cancer patients who have undergone breast-conserving surgery may not produce enough milk, and the milk may lack some essential nutrients. However, breastfeeding is not recommended while the patient is undergoing aggressive antitumor therapy (e.g., chemotherapy, endocrine therapy).
In conclusion, breast cancer patients who wish to become pregnant can do so, but it is best to avoid the peak of recurrence and choose to become pregnant 2 or 5 years after the end of adjuvant therapy (for advanced patients), depending on your doctor’s opinion. (Contributed by Yang Yuqing, Department of Nail and Breast Vascular Surgery, Xijing Hospital, Air Force Military Medical University)