After a breast cancer diagnosis, once you have spent a long while gathering yourself, an unexpected topic sometimes comes up at the meeting where you hear the treatment plan. Not chemotherapy or radiation, but an injection into the belly once a month or once every three months. It even has an unfamiliar name — the "ovarian function suppression injection." You have not even reached menopause yet, so why are they telling you to stop the ovaries? It is only natural to be flustered when you first hear it.
The key is the female hormone, and among them, estrogen. Quite a few types of breast cancer grow by feeding on this hormone. If your test report says ER positive or hormone receptor positive, that is exactly the case. In premenopausal women, estrogen is actively produced in the ovaries. So from the cancer cells point of view, food is being supplied constantly. The ovarian function suppression injection temporarily shuts off that supply line. It works by quietly silencing the pituitary gland, which sends signals to the ovaries, so that the ovaries end up producing almost no hormone.
Then you might wonder whether you cannot just take one drug, and in fact many people do exactly that. For some, an anti-hormone drug like tamoxifen alone is enough. However, when you were young at the time of diagnosis, when there was lymph node metastasis, or when the tumor character was aggressive so the risk of recurrence came out a bit higher, the story is different. In such cases, research has accumulated showing that adding ovarian suppression as well can lower the chance of recurrence by another notch. Whether or not to actually get the injection is something decided by weighing that persons risk level and physical condition together.
Of course, it is not free. When you stop the ovaries, the body suddenly enters a menopausal state. Hot flashes that make your face flush, cold sweats, disturbed sleep, and a stiff, achy feeling in the joints may come. People say it feels like receiving in advance the change of life that would come a few years later. The good news is that this generally recovers once you stop the injections. It is different from surgery that permanently removes ovarian function. If you are still planning to have children, you must be sure to go over this point with your medical team.
The treatment period is usually set long, on the scale of several years. Coming to the hospital for an injection each time is a hassle, and there are certainly days when the side effects bother you. Even so, the reason this injection is recommended comes down to one thing: to lower the chance of cancer returning later, even if it is a little uncomfortable now. If the hot flashes are too severe or daily life becomes hard, do not endure it — tell your doctor. Together you can find ways to adjust the intensity or manage the symptoms.
What is written here is only a general explanation, and the answer that fits your body ultimately comes from the consultation room. I hope you will talk things over fully with your medical team, bringing your test results.