New treatments for metastases

One in four breast cancer patients develop metastases. If they are only in the axillary nodes close to the breast, there is still a chance of healing. The treatment is then aimed at removing the metastases completely. If there are metastases in other places in the body, then healing is not (yet) possible. The treatment is then intended to save time and to combat complaints, such as pain. Most patients with metastatic breast cancer live an average of three years from the time of diagnosis. This ‘survival time’ is getting longer, thanks to better treatments.

Breast cancer: extra years for some patients

Broadly speaking, there are three types of breast cancer. The worst is ‘triple negative’: the cancer is hormone insensitive and the protein HER2 is absent. 10 percent of patients have it. Most live less than two years after diagnosis. New drugs are under development.

About 70 percent of patients have hormone-sensitive breast cancer with few metastases. They first receive hormone therapy, but after a while this no longer works well. Recently, new drugs can delay the step to chemotherapy by several months.

For patients with a lot of HER2 protein (20 percent) there are new drugs: the HER2 inhibitors. With this they now live an average of about four years; this was less than two. In addition to hormone or chemotherapy, they often receive immunotherapy with trastuzumab. “There is promising research in which this drug is linked to a toxic substance that damages the cancer cell. This will soon be available in the Netherlands for patients with metastatic breast cancer with the HER2 protein,” says professor of medical oncology Epie Boven of the VU University Medical Center in Amsterdam.

The latest breast cancer news can be found at breast cancer.nl, the site of the Breast Cancer Association of the Netherlands, where (former) patients can also share experiences and find support.

Prostate cancer: many new drugs

Metastases are also common in prostate cancer. At the time of diagnosis, 15 percent have metastases. Another 20 percent develop them later. Patients with metastases live an average of two years. Without metastases, the disease can often be controlled for years with hormone therapy.

At some point, that treatment no longer works. A patient who has become hormone insensitive then lives on average for another two years. There are several treatments so that patients suffer less from pain, for example. They usually receive chemotherapy (Docetaxel) first. Maureen Aarts, internist-oncologist at the Maastricht University Medical Center: “The outlook is improving because new drugs are becoming available.”

New medicines

There are a few new drugs that can be used after treatment with Docetaxel and that prolong life by several months (cabazitaxel, Abiraterone and Enzalutamide). Maureen Aarts expects that ‘targeted therapies’ will soon be introduced that destroy the cancer cells in prostate cancer. That would be a big step forward. Earlier this year, the results of a study with very promising results were published, in which the bone metastases were much less in 68 percent of the patients. At 12 percent they had even completely disappeared. A larger study has recently been completed. If the results of this are also as good, Aarts says it will take another two to three years before the drug becomes available.

Melanoma: big steps forward

The development of melanoma (a form of skin cancer) is the most favorable of all types of metastatic cancer. For example, Vemurafenib, a ‘targeted therapy’, works very well in half of the patients with metastatic melanoma. But it only works for half a year on average. In addition, there are three new types of immunotherapy.

Prof. dr. Daniel Peeper, head of Molecular Oncology at the Antoni van Leeuwenhoek: “Combinations in particular show a spectacular improvement, but so far this approach has only been studied in clinical trials, in other words: in tests with test subjects. These combinations also have many side effects. There are patients whose disease has been gone for two years now. Perhaps there are people who can ultimately be declared cured.” In the long run, Daniel Peeper expects drug cocktails (just as happened with HIV) to make melanoma a chronic disease, or even be cured. Experts hope that such steps can also be taken in other forms of cancer.

Treatments

What do the different treatments mean?

• Hormonal therapy: Some hormones in the body make it easier for cancer cells to grow or spread. Hormone therapy prevents this.
• Radiation: Topical treatment that destroys cancer cells. The surrounding healthy cells are spared as much as possible.
• Targeted therapy: Comes in different forms. An example: small molecules can block signals in the cancer cell, so that the cell can no longer divide or die.
• Immunotherapy: Drugs that stimulate an immune response against cancer cells. This prevents the cancer cells from dividing. Many new drugs are under development for this therapy.