According to results presented at the 2002 annual San Antonio Breast Cancer Symposium, dose-dense chemotherapy regimens improved survival by 31% in patients with breast cancer.
Chemotherapy not only destroys cancer cells, but also normal cells that grow rapidly, such as blood cells forming in the bone marrow, cells in the hair follicles, or cells in the mouth and intestines. Neutropenia occurs when white blood cells (immune cells) are destroyed by chemotherapy, leaving the immune system unable to fight bacterial, viral and fungal infections. Chemotherapy induced neutropenia can become a serious condition for several reasons: the majority of patients who develop neutropenia will require a dose reduction in their treatment which may reduce survival rates, patients who develop neutropenia may require hospitalization and even minor infections can become life threatening.
Neupogen® is an agent that stimulates the production of white blood cells and is approved for the treatment of neutropenia. Clinical studies have indicated that early treatment with Neupogen® reduces the incidence of neutropenia, allowing for patients to tolerate optimal chemotherapy doses. The recent clinical trial evaluating women with breast cancer was designed to determine whether giving chemotherapy doses closer together (dose-dense) improved outcomes. Patients in this trial underwent the surgical removal of their breast cancer and axillary lymph nodes and then were treated with the chemotherapy combination consisting of paclitaxel (Taxol®), cyclophosphamide(Cytoxan®) and doxorubicin (Adriamycin®). One group of patients received the chemotherapy combination once every two weeks routinely supported with Neupogen® to ensure fast recovery of white blood cells and prevent delay of the rest of the chemotherapy cycle. The other group of patients received the same chemotherapy combination once every three weeks and were only treated with Neupogen® when their white blood cell levels were lowered due to the chemotherapy. Patients receiving the Neupogen® supported chemotherapy combination once every two weeks had an improved survival by 31% compared to the group of patients receiving chemotherapy once every three weeks.
One drawback of Neupogen® is that it must be administered daily. In an effort to address the daily dose requirements of Neupogen®, researchers developed
Neulasta™, which also stimulates the production of white blood cells. Unlike Neupogen®, Neulasta™ may be administered as a single dose per chemotherapy cycle. Previous clinical trials have indicated that Neulasta™ reduces the incidence and/or severity of neutropenia in patients undergoing treatment for non-myeloid (blood) cancer and further trials are being conducted to determine the true clinical efficacy of treatment with Neulasta™. Researchers speculate that Neulasta™ may someday replace Neupogen® for many patients in the prevention and/or treatment of neutropenia.
These researchers concluded that continual use of Neupogen® throughout a chemotherapy cycle may prevent the incidence of neutropenia and allow patients to tolerate optimal chemotherapy dosing. According to results from this trial, more frequent dosing of chemotherapy appears to significantly improve survival in breast cancer patients. Patients diagnosed with breast cancer who are to undergo chemotherapy may wish to discuss the risks and benefits of treatment with Neupogen® or Neulasta™ to prevent neutropenia during their course of therapy. Two sources of information regarding ongoing clinical trials include the National Cancer Institute (cancer.gov) and www.eCancerTrials.com eCancerTrials.com also provides personalized clinical trial searches on behalf of patients.