When I was first diagnosed with breast cancer, my doctor explained that there were many kinds of chemotherapy treatments. It was amazing, and a bit overwhelming, to learn how tailored the treatment would be to address the specific details of the cancer in my breast. The pathology report gave information about the molecular structure of the cancer and the rate at which it was growing. The MRI and PET scans, along with the surgeon's report from my mastectomy, informed us of the extent to which the cancer had spread. These details allowed my team of oncologists to form a chemotherapy treatment plan that would give me the best shot at overcoming the cancer while limiting the side effects of the treatment.
There are a number of different strategies that oncologists can use to tailor chemotherapy to the patient, and the strategies available vary according to the type of cancer and the affected parts of your body.
Targeted therapies specifically target a protein or other molecules and have the benefit of reducing chemo side effects.
I learned that the cancer in my breast was HER2-positive, meaning that the cancer cells contained a protein called human epidermal growth factor receptor 2 (HER2). According to the Mayo Clinic, this mutation causes the cancer to be especially aggressive, but the protein exists only in the cancer cell. Targeted therapies have been developed that only go after the cells that contain the HER2 protein. Two commonly used agents for HER2-positive cancers are Trastuzumab (Herceptin) and Lapatinib (Tykerb).
Activated hormone receptors change the way that a gene is expressed. That means these receptors change the way that the gene behaves, often stimulating cell growth. Hormone-sensitive cancer cells have extra hormone receptors. This increases the likelihood that the hormone will change the gene expression and cause the cancer cells to grow. To stop this process, hormones are blocked from binding with the hormone receptors by drugs such as tamoxifen. The production of estrogen can be stopped with an aromatase inhibitor such as anastrozole (Arimidex) or letrozole (Femara). In some cases, the ovaries may be removed to permanently reduce the estrogen in the system.
The cancer that grew in my breast was not hormone-sensitive, so there was no need to permanently block estrogen production. However, my oncologist did prescribe Zoladex to temporarily stop my ovaries from functioning in order to protect my ovaries from the chemotherapy. This treatment was done with the hope of preserving my fertility.
Dose-dense chemotherapy treatment refers to treatments that are timed to occur close together. If conventionally scheduled chemotherapy treatments are once every three weeks, the dose-dense schedule might be once every two weeks. This strategy is used for more advanced cancers that are starting to spread. At the time of my surgery, the tumor was large, and the cancer had spread to my lymph nodes. Because of this, I was put on a dose-dense chemotherapy schedule to more aggressively treat the cancer.
Combined Modality Chemotherapy
Combined modality simply means using more than one type of therapy to treat the cancer. In my case, because my cancer was aggressive and at stage 3, my doctors prescribed surgery, chemotherapy, radiation, and then a year of Herceptin. Not everyone will require that much treatment, although some people will require more.
Palliative therapy is treatment that is given to improve quality of life. The purpose of palliative care is to ease pain and reduce the tumor size to improve organ function, rather than to eliminate the cancer altogether. While it is often thought of as a long-term end-of-life strategy to provide comfort, palliative care can also be a temporary addition to the treatment strategy at any point in the process to address a quality-of-life issue.
There are so many types of treatments that this is not an exhaustive listing of all the chemotherapy strategies available to oncologists. The American Cancer Society and the National Cancer Institute both offer resources that you can use to look up unfamiliar treatments or terms. Research continues to develop new treatments and more strategies for using existing treatments.
So just know that, if one doesn't work, there are usually more to try.