Herceptin very effective in HER2+ breast cancer
|
|
Two studies published in The New England Journal of Medicine show that treatment with trastuzumab (Herceptin; Roche) can dramatically improve outcomes in women with breast cancers that are HER2-positive.
HER2 overexpression occurs in approximately 15 percent to 25 percent of breast cancers and is associated with a worse prognosis than HER2-negative tumors.
Dr. Martine J. Piccart-Gebhart and members of the Herceptin Adjuvant (HERA) Trial Study Team enrolled patients with HER2-positive, early stage breast cancer who underwent surgery to removed the tumor and at least four cycles of chemotherapy. A total of 1,694 women were then assigned to 1 year of treatment with Herceptin, a humanized monoclonal antibody, and 1,693 patients were assigned to observation only.
At 1-year follow-up, there were 127 events, including recurrence of breast cancer, breast cancer in the other breast, or a second malignant disease in the Herceptin group and 220 in the observation group, a statistically significant difference. Mortality rates were similar in the two groups.
“This degree of benefit in early breast cancer is the largest to be reported since the introduction of tamoxifen in hormone-receptor-positive disease,” the authors note.
There were more serious adverse events (7.0 percent versus 4.7 percent) among women given Herceptin than in those in the comparison group. Symptomatic heart failure developed in 1.73 percent in the Herceptin group and 0.06 percent in the observation group.
Piccart-Gebhart’s team advises that 1 year of Herceptin should be considered a standard option after surgery or chemotherapy in women who fulfill the eligibility criteria used in this trial.
In a second paper in the Journal, Dr. Charles E. Geyer, Jr., at the Allegheny Cancer Center in Pittsburgh, and colleagues present combined results of the National Surgical Adjuvant Breast and Bowel Project trial B-31 and the North Central Cancer Treatment Group trial N9831. The two studies were amended to include a joint analysis.
Following tumor removal, patients in both groups were treated with doxorubicin and cyclophosphamide followed by paclitaxel. One group of 1,679 patients then received Herceptin for 1 year. There were 1,672 patients who followed the same course of treatment but received concomitant paclitaxel and Herceptin for 1 year.
During a follow-up of 2 years, there were 133 events in the Herceptin group and 261 in the control group, a statistically significant difference. Herceptin reduced the mortality rate by one third, the authors note.
As in the HERA study, there was an increased rate of congestive heart failure associated with Herceptin. “Clearly, appropriate selection and careful cardiac monitoring of patients are essential,” Geyer’s group indicates.
These results are “simply stunning,” and “not evolutionary but revolutionary,” Dr. Gabriel N. Hortobagyi, from the University of Texas M. D. Anderson Cancer Center in Houston, states in a related editorial. “With very brief follow-up…all three trials show highly significant reductions in the risk of recurrence, of a magnitude seldom observed in oncology trials.”
SOURCE: The New England Journal of Medicine, October 20, 2005.
Print Version
Tell-a-Friend comments powered by Disqus
