When breast cancer has spread to parts of the body away from the breast, it's called metastatic cancer. Breast cancer can spread to bones, the lungs, the liver, and the brain. Metastatic breast cancer is treatable, but generally not curable. About 30% to 40% of women with metastatic breast cancer have the cancer spread to the brain.
Metastatic breast cancer that has spread to the brain can cause neurological symptoms, including trouble moving, speaking, swallowing, learning, and remembering. Treatment for metastatic breast cancer in the brain is aimed at weakening and shrinking the cancer. Sometimes doctors will surgically remove the cancer if it's possible to do so. If surgery isn't possible, the cancer may be treated with radiation therapy to the brain. But brain radiation also can cause neurological side effects. So doctors have been looking for another way to treat metastatic breast cancer in the brain that would replace or delay brain radiation.
A small, early study found that treating women diagnosed with metastatic, HER2-positive breast cancer that had spread to the brain with a combination of Tykerb (chemical name: lapatinib) and Xeloda (chemical name: capecitabine) can stabilize, weaken, and shrink the cancer in some women. So the combination of Tykerb and Xeloda may delay the need for brain radiation in some women.
Both Tykerb and Xeloda are pills taken by mouth.
The research is published in the Journal of Clinical Oncology and was presented at the 2011 annual meeting of the American Society of Clinical Oncology (ASCO).
HER2-positive cancers make too much of the HER2 protein. The HER2 protein sits on the surface of cancer cells and receives signals that encourage the cancer cells to grow and spread. About one out of every four breast cancers is HER2-positive. Two targeted therapies, Tykerb and Herceptin (chemical name: trastuzumab), work by blocking the HER2 protein's ability to make HER2-positive breast cancers grow.
Tykerb is approved to be used in combination with Xeloda to treat HER2-positive, metastatic breast cancers that have stopped responding to certain chemotherapy medicines and Herceptin. Tykerb also is approved to be used in combination with the hormonal therapy Femara (chemical name: letrozole) to treat postmenopausal women diagnosed with hormone-receptor-positive, HER2-positive, advanced-stage breast cancer.
In the LANDSCAPE trial, 44 women newly diagnosed with HER2-positive, metastatic breast cancer that had spread to the brain were treated with a combination of Tykerb and Xeloda. Most of the women had more than one area of cancer in the brain; the average was three. The cancers in the brain were all at least 1 centimeter in size (about one-half inch). Surgery to remove the breast cancer in the brain wasn't an option for any of the women.
The researchers kept track of how many women had some response to the treatment, the level of response, and how much time passed before the women needed brain radiation. Half of the women were followed for more than 14 months; the others were followed for shorter time periods.
- Nearly all the women showed some response to treatment and in two-thirds (67.4%), the areas of cancer in the brain shrank in size by at least half.
- 14% of the women showed signs that the areas of cancer in the brain were growing during follow-up.
- 24 women had neurological symptoms when the study started; 14 of them had those symptoms ease with treatment.
- Three-fourths of the women (74.4%) eventually had to have brain radiation; about 8 months passed before radiation was needed.
- At 6 months of follow-up, 90% of the women were alive.
About 31% of the women had serious side effects from the treatment. The most common were diarrhea and hand-foot syndrome. Both side effects are associated with both Tykerb and Xeloda. Hand-foot syndrome is a skin reaction that occurs when a small amount of medicine leaks out of capillaries (small blood vessels), usually into the palms of the hands and soles of the feet. The leaked medicine can damage the surrounding tissue. This can cause pain that's sometimes severe and make it hard to use your hands or walk.
While the results are promising, more research is needed to help doctors understand who would most benefit and when to use the Tykerb-Xeloda combination to treat metastatic breast cancer that has spread to the brain.
If you've recently been diagnosed with breast cancer brain metastases, you may want to ask your doctor about this study and whether the combination of Tykerb and Xeloda may be a good option for your unique situation.