Many options for treatment
Dr. Ian Krop of Dana-Farber's Breast Oncology Center says he's optimistic that metastatic breast cancer can become a "very manageable condition."
When breast cancer has spread through the blood or lymph circulation and is no longer curable, the goal of treatment is to extend survival as long as possible and maintain quality of life.
A woman whose cancer requires estrogen to grow will likely benefit from hormonal agents such as tamoxifen or one of the newer aromatase inhibitor drugs. Patients whose metastatic breast cancers are independent of estrogen, or ER-negative, usually receive standard chemotherapy agents such as paclitaxel (Taxol). Women with breast cancers that have an overactive cell growth signal called HER2, have benefited greatly from the targeted drug trastuzumab, or Herceptin, which blocks the HER2 signal. Herceptin given along with conventional chemotherapy has proven to shrink tumors, delay the worsening of breast cancer, and prolong life.
The newest treatments are designed to focus on specific molecular targets present only in breast cancer cells. Because of this selectivity, these drugs are generally less toxic than the traditional agents. Herceptin, for example, doesn't cause the hair loss that conventional chemotherapy agents often do.
Herceptin, which first became available apart from clinical trials in 1998, was the first of a new generation of targeted drugs for breast cancer. It doesn't work for all HER2-positive patients, and now a newer targeted compound, lapatinib (Tykerb), has been approved for use with capecitabine (Xeloda), an oral cancer drug, for patients whose HER2-positive metastatic breast cancer is resistant to Herceptin.
Wind fills the sails as Miriam Shafner casts her eyes aloft.
Another promising strategy is embodied in bevacizumab, or Avastin, which combats tumors by blocking their blood supply. It is being tested in several trials for metastatic breast cancer.
Researchers are still learning how best to use these new drugs, and while it's too soon to know how far they will take women with breast cancer, they represent a step toward greater use of "smart," less-toxic therapies. Dr. Winer adds that in the not-too-distant future, physicians will be able to fine-tune and individualize treatment to match the genetic and biological characteristics of a woman's cancer — so-called "personalized medicine."
Increasingly, patients like Riley and Shafner have been spared some of the most debilitating side effects of therapy. "Chemotherapy is kinder and gentler than it used to be, and both hormonal therapy and the new generation of targeted therapies are relatively easy for a patient to tolerate," observes Dr. Winer. Breast oncologist Harold Burstein, MD, adds that symptoms can be managed more effectively, thanks to everything from greatly improved anti-nausea medications to bisphosphonate drugs for bone pain and closer collaboration among different specialists to better focus on the patient.
It all adds up to a somewhat brighter picture of this forbidding type of cancer, with the promise of more light to come in the years ahead. "There are many effective tools and treatments for advanced breast cancer," says Dr. Burstein. "Guided by tumor biology, patient preferences, and real progress in development of new drugs, we are making headway against this disease."
