Higher Dose of Faslodex® More Effective for Advanced Breast Cancer
5 October 2010
Annals of Surgical Oncology
Among postmenopausal women with advanced, estrogen receptor-positive breast cancer that has progressed or recurred after prior hormonal therapy, a 500 mg dose of Faslodex® (fulvestrant) appears to be more effective than the originally approved 250 mg dose. These results were published in the Journal of Clinical Oncology. As a result of these findings, the 500 mg dose was recently approved by the U.S. Food and Drug Administration (FDA).
Each year roughly 200,000 U.S. women are diagnosed with breast cancer. Many of these breast cancers will be hormone receptor-positive, meaning that they are stimulated to grow by the circulating female hormones estrogen and/or progesterone. Treatment of hormone receptor-positive breast cancer often involves hormonal therapies that suppress or block the action of estrogen.
Faslodex—a type of hormonal therapy known as an estrogen receptor antagonist—blocks the actions of estrogen. It’s used for the treatment of metastatic, hormone receptor-positive breast cancer in postmenopausal women who experience cancer progression or recurrence after prior hormone therapy. Until recently, a standard dose of Faslodex was 250 mg.
In order to assess the effects of a higher dose of Faslodex, researchers conducted a Phase III clinical trial known as CONFIRM (Comparison of Faslodex in Recurrent or Metastatic breast cancer). The study compared the 250 mg dose of Faslodex to a 500 mg dose among 736 women in 17 countries.
- Compared with the lower dose, the higher dose of Faslodex delayed cancer progression. Median time to cancer progression was 6.5 months among patients treated with the 500 mg dose and 5.5 months among patients treated with the 250 mg dose.
- After one year 34% of patients treated with the 500 mg dose were alive and free of cancer progression compared with 25% of patients treated with the 250 mg dose.
- No new safety concerns were identified with the 500 mg dose. The most common side effects included nausea, bone pain, back pain, and injection site pain.
The results of this study indicate that the 500 mg dose of Faslodex improves progression-free survival without increasing side effects. Based on these findings, the FDA approved the 500 mg dose for postmenopausal women with hormone receptor-positive, metastatic breast cancer that has progressed after antiestrogen therapy.
Reference: Di Leo A, Jerusalem G, Petruzelka L et al. Results of the CONFIRM Phase III trial compared fulvestrant 250 mg with fulvestrant 500 mg in postmenopausal women with estrogen receptor-positive advanced breast cancer. Journal of Clinical Oncology [early online publication]. September 20, 2010.
Freezing breast tumors helps stop cancer’s spread in mice, U-M study finds
Cryoablation generates immune response that kills metastases in mice
Clinical trial open now to evaluate this technique in patients
3 March 2010
Annals of Surgical Oncology
Ann Arbor - Freezing a cancer kills it in its place, and also appears to generate an immune response that helps stop the cancer's spread, leading to improved survival rates over surgery, according to a new study in mice from researchers at the University of Michigan Comprehensive Cancer Center.
Researchers looked at two different cryoablation techniques, which both involve applying a cold probe to a tumor to freeze it. The study was done in mice with breast cancer. One method involves freezing the tumor rapidly, in about 30 seconds; the other freezes the tumor slowly, taking a few minutes. Results from the cryoablation were compared to results from mice whose tumors were removed with surgery.
Both cryoablation techniques successfully killed the breast tumor. The mice treated with the rapid freeze had fewer tumors that spread to the lungs and improved survival compared to mice treated with surgery alone or mice treated with the slower freezing technique. The study showed that the benefit from the rapid freezing is likely due to changes in the immune system that help to kill the tumor. Freezing with the slower technique appeared to make the immune system not as able to kill the tumor.
The study appears online in Annals of Surgical Oncology. Based on these results from mice, researchers are now conducting a clinical trial using cryoablation in patients with breast cancer. In this trial, researchers use the rapid freezing technique.
"Cryoablation has strong potential as a treatment for breast cancer. Not only does it appear effective in treating the primary tumor with little cosmetic concerns, but it also may stimulate an immune response capable of eradicating any cells that have traveled throughout the body, reducing both local and distant recurrence, similar to giving a breast cancer vaccine," says lead study author Michael Sabel, M.D., associate professor of surgery at the U-M Medical School.
"What we learned in this study is that all cryoablation is not equal. The technique used to freeze the tissue can have a significant impact on how the immune system responds. The system we use today appears to be ideal for both destroying the tumor within the breast and generating an anti-cancer immune response," Sabel says.
U-M researchers are participating in a national clinical trial to evaluate using cryoablation for early stage breast cancer. Participants will undergo rapid freezing of their tumor, and their blood samples will be analyzed to assess changes in their immune system. All participants will be treated three to four weeks later with standard surgery to remove their tumor.
For more information about the study, contact the U-M Cancer AnswerLine at 800-865-1125.
Cryoablation is currently used routinely for prostate cancer, kidney cancer and a variety of cancers that have spread to the liver and bone.
Breast cancer statistics: 192,280 Americans will be diagnosed with breast cancer this year and 40,610 will die from the disease, according to the American Cancer Society.
Funding: No external funding.
Reference: Annals of Surgical Oncology, DOI 10.1245/s10434-009-0846-1.