Early breast cancer patients treated with standard chemotherapy followed by paclitaxel (Taxol) had better disease-free survival compared with patients treated with standard therapy alone, according to the final results from a randomized phase III trial.
Paclitaxel and other taxanes are among the most active agents in metastatic breast cancer. Researchers are now testing the drugs in patients with early, non-metastatic breast cancer.
In the current study, Miguel Martín, M.D., of the Spanish Breast Cancer Research Group and colleagues randomly assigned 1,246 women to treatment with fluorouracil, epirubicin, and cyclophosphamide (FEC) or FEC followed by weekly paclitaxel (FEC-P).
The estimated 5-year survival rate was 78.5 percent in the FEC-P arm and 72.1 percent in the FEC arm. There was a trend toward improved overall survival, but it did not reach statistical significance. “Because distant relapse-free survival is usually associated with overall survival, a statistically significant benefit in overall survival may become evident with a more protracted follow-up,” the authors write.
A retrospective analysis of the data failed to detect a subgroup of patients who were more likely to respond to taxane therapy on the basis of their tumor’s expression of the estrogen receptor and HER2.
In an accompanying editorial, Clifford Hudis, M.D., and Chau Dang, M.D., of Memorial Sloan-Kettering Cancer Center in New York review several trials that tested the potential benefit of adding taxanes to existing adjuvant therapy. From that point of view, the study by Martín and colleagues is important because it is well designed and uses a good regimen and schedule of drugs.
They emphasize that retrospective analyses should be considered hypothesis generating only, particularly when the results from several similar analyses are inconsistent “If you accept that the taxanes are effective, hormone receptor and HER2 status should not routinely guide your selection of patients for this therapy,” the editorialists conclude. http://jnci.oxfordjournals.org