This article is more than 5 years old. Information may no longer be current.
Recurrence scores predicted benefit from anthracycline-based chemotherapy
Click Here to Manage Email Alerts
San Antonio Breast Cancer Symposium
Mature results from SWOG-8814 indicate that postmenopausal women with ER-positive breast cancer with involved axillary lymph nodes benefited from the addition of chemotherapy to standard tamoxifen treatment. However, a second retrospective analysis showed that the 21-gene recurrence score assay was able to predict which of these same patients would benefit from the addition of chemotherapy to tamoxifen vs. Who could avoid chemotherapy.
The results of SWOG-8814 were published in The Lancet; the results of the retrospective analysis were presented at the San Antonio Breast Cancer Symposium by Kathy S. Albain, MD, professor of medicine with Loyola University Health System and published in The Lancet Oncology.
In SWOG-8814, two objectives were tested. The primary outcome was whether disease-free survival was longer with cyclophosphomide, doxorubicin and fluorouracil plus five years of tamoxifen than with tamoxifen alone, and whether tamoxifen was more effective given after chemotherapy or concurrent to it. Patients were randomly assigned to tamoxifen only, chemotherapy followed by tamoxifen (CAF-T) or chemotherapy concurrent to tamoxifen (CAFT).
Of 1,588 women, 95% were eligible for the final analysis. Median follow-up was nine years. At 10 years, 60% of women treated with CAF-T were free of recurrence or death due to any cause, compared with 53% on CAFT and only 48% on tamoxifen alone. An analysis that adjusted for important prognostic factors showed that women in the combined CAF-T/CAFT groups were 24% less likely to experience a breast cancer recurrence or death than those given tamoxifen alone, and 17% more likely to survive. The proportions of women alive at 10 years were 68%, 62% and 60%, respectively, for CAF-T, CAFT and tamoxifen.
Multigene assay
Researchers then performed a retrospective study on 367 women from SWOG-8814 to determine whether the 21-gene recurrence score assay OncotypeDX could predict which patients with breast cancer would benefit from chemotherapy in terms of disease-free survival, OS and breast-cancer-specific survival.
Patients were also evaluated for 10-year disease-free survival within nodal categories (one to three positive nodes and four or more positive nodes) by the linear recurrence score.
“We found the group with a low recurrence score over 10 years does not seem to benefit from chemotherapy with CAF,” Albain said in an interview. “This was regardless of nodal status. Patients in either the one to three node group or the four or more node group, over 10 years, who had the lowest recurrence scores did not benefit.”
However, researchers found a strong benefit from chemotherapy in patients whose tumors had high recurrence scores. Their observations were true for each endpoint tested (disease-free survival, OS and breast-cancer-specific survival).
At 10 years, breast cancer specific-survival for patients with low recurrence scores was 90% despite positive nodal status, Albain said. She added there appeared to be no chemotherapy benefit for these patients.
“We are planning a prospective study to confirm these findings. Until then, women with positive lymph nodes should discuss with their physicians whether a very low recurrence score could provide a no chemotherapy option for them,” she said. – by Jason Harris
For more information:
- Albain KS. #112. Presented at: the 2009 San Antonio Breast Cancer Symposium; Dec. 8-12, 2009; San Antonio, Texas.
- Albain KS. Lancet. 2009;doi:10.1016/S1470-2045(09)70314-6.
Follow HemOncToday.com
on Twitter.