In addition, targeted therapies tend to have far fewer side effects than chemotherapy drugs.
As such, the diagnosis often comes as a shock to many.
With HER2-positive cases specifically, HER2 genes overproduce HER2 proteins.
Verywell / Brianna Gilmartin
Growth factors bind to these receptor proteins on breast cancer cells, causing the growth characteristic of these tumors.
But unlike with early-stage breast cancerin which several options (surgery, chemotherapy, radiation, etc.)
It does, however, increase side effects.
As such, theleastamount of treatment needed to control the disease is what doctors aim for in metastatic cases.
If your tumor is both estrogen-receptor-positiveandHER2-positive, initial treatment may includehormonal therapy, a HER2-targeted therapy, or both.
For those who have previously been treated with Herceptin, another HER2-targeted drug may be used.
Third line optionswill vary depending on prior treatments.
For those who haven’t yet been treated with T-DM1, this drug is an option.
Perjeta may also be used for those who have not yet received it in combination with Herceptin.
In a 2018 study, palliative mastectomy was found to improve quality of life for some people.
This means that the disease is different than if the cancer originated in these areas.
That said, treatments that are “metastasis-specific” may be used as well.
These are treatments that specifically address the area to which the cancer has spread.
Radiation therapyis commonly used in addition to other treatments for the cancer.
Other treatments such asembolizationmay be considered as well.
Itching is also very common with liver metastases and treatment to manage this symptom can improve quality of life.
Thankfully, some drugs are able to cross over.
Trastuzumab emtansine (T-DM1) and Perjeta (pertuzumab) are also promising.
When lapatinib is combined with chemotherapy, however, the response rates are better.
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