Fertility After Targeted Therapy

There are three targeted therapy medicines that are approved to treat breast cancer in premenopausal women:

• Herceptin (chemical name: trastuzumab) can be used to treat metastatic HER2-positive disease and earlier stages of HER2-positive disease after surgery.
• Tykerb (chemical name: lapatinib) can be given in combination with Xeloda (chemical name: capecitabine), a type of chemotherapy, to treat advanced-stage, HER2-positive breast cancer that has stopped responding to anthracyclines, taxanes, and Herceptin; and in combination with Femara (chemical name: letrozole), a type of hormonal therapy, to treat postmenopausal women diagnosed with hormone-receptor-positive, HER2-positive advanced-stage breast cancer.
• Avastin (chemical name: bevacizumab) was approved by the U.S. Food and Drug Administration (FDA) in combination with Taxol (chemical name: paclitaxel) in February 2008 to treat people with metastatic HER2-negative breast cancer who haven't yet received chemotherapy for metastatic breast cancer.
  
  On December 16, 2010, the U.S. Food and Drug Administration announced that it is recommending removing the breast cancer indication from Avastin because the drug has not been shown to be safe and effective for that use. Removing the breast cancer indication from Avastin will be a process. This is the first step. The medicine itself is not being removed from the market and the recommendation will not have any immediate impact on its use in treating breast cancer.

Because targeted therapy medicines are relatively new compared to other breast cancer treatments, not much research has been done on how they may affect fertility. Because the medicines are targeted -- meaning they target specific characteristics of cancer cells, such as a protein that allows cancer cells to grow in an abnormal way -- they're generally less likely than chemotherapy to harm normal, healthy cells. It's also encouraging to know that women who have been treated with Herceptin have become pregnant after their treatment was completed.

Most doctors recommend waiting 6 months to a year before becoming pregnant after targeted therapy treatment.