Herceptin (chemical name: trastuzumab) is one of the first targeted therapies used to treat breast cancer. It specifically attacks, kills off, or stops the growth of cells that make too much of a protein called HER2/neu—and it leaves most normal cells alone. About one out of every four breast cancers are "HER2/neu positive"—they make too much of this protein.
Herceptin works differently than standard chemotherapy. As chemotherapy kills cancer cells, it can also damage normal cells that are rapidly dividing. This is why chemotherapy causes more side effects than Herceptin. In contrast, Herceptin is a more targeted treatment—it only kills off or stops the growth of cells that make too much HER2/neu.
Herceptin will only work if the tumor is HER2/neu positive. To find out whether Herceptin is likely to work for you, your doctor will do a special test to see whether the type of cancer you have might respond to Herceptin.
Herceptin is given every week, every two weeks, or every three weeks by a needle placed into a vein (intravenously). You can take Herceptin alone or combine it with other chemotherapies or hormonal therapies. Studies suggest that Herceptin tends to work better when it is combined with chemotherapy such as:
- Taxol (chemical name: paclitaxel)
- Taxol and Paraplatin (chemical name: carboplatin)
- Navelbine (chemical name: vinorelbine)
Herceptin is being tested in combination with these chemotherapies:
- Abraxane (chemical name: albumin-bound or nab-paclitaxel)
- Abraxane and Gemzar (chemical name: gemcitabine)
- Taxotere (chemical name: docetaxel)
- CMF (cyclophosphamide, methotrexate, and fluorouracil)
- Gemzar (chemical name: gemcitabine)
- Xeloda (chemical name: capecitabine)
None of these combinations include chemotherapy with Adriamycin (chemical name: doxorubicin). That's because the risk of heart damage is too high when Herceptin is given together with this kind of chemotherapy. One study found that the risk of having heart problems is much lower when Herceptin is combined with Taxol than when it is combined with Adriamycin.
It may take several months before you see an improvement with Herceptin. One study suggested that you can still benefit from taking Herceptin even if the breast cancer appears to get worse while you are taking it.
Herceptin's side effects tend to be mild. It does NOT cause hair loss, stomach upsets, or an increased risk of infection.
In rare cases (1% to 5% of women), Herceptin can cause:
- damage to the heart that affects its ability to pump well (more likely to happen if you also take Adriamycin or have taken it in the past)
- allergic reactions
- buildup of fluid in the lungs
In very rare cases, Herceptin causes flu-like symptoms that become less severe with each treatment.
Some women feel pain in the area where the cancer is growing. This pain is described as a "burning" and usually happens during the treatment or within a few hours after the treatment. Women who do not have this pain should not worry that the drug is not working.
Get as much information as you can about Herceptin.