Current guidelines call for no additional therapy after surgery and radiation if tumors are less than five millimeters and Herceptin-based adjuvant therapy should be discussed with patients if the tumors are from six to 10 millimeters, Gonzalez-Angulo explained.
According to Gonzalez-Angulo, the number of patients with HER2 positive tumors smaller than one centimeter continues to increase as breast cancer surveillance and early detection become increasingly sophisticated.
"Before now, there's been no data regarding how to treat these women because they were excluded from all the definitive trials confirming Herceptin's benefit. This data strongly suggests that we need to rethink how we treat early-stage breast cancer patients with HER2 positive tumors and likely offer anti-HER2 therapy in the adjuvant setting."
For the retrospective study, Gonzalez-Angulo, Ranjay Rakkhit, M.D., a fellow in M. D. Anderson's Department of Hematology and Oncology and the study's first author, and their colleagues used M. D. Anderson's Breast Cancer Research Database to analyze 965 patients treated between 1990 and 2002. All of the patients' tumors were smaller than one centimeter; patients whose receptor status could not be analyzed and/or had received adjuvant chemotherapy or Herceptin at any time were excluded. The median age of the women at diagnosis was 57 years. To validate the findings, a second cohort of 350 patients from European institutions was also analyzed.
Of the M. D. Anderson patient population, more than 10 percent, or 98 patients, had HER2 positive tumors. In addition, 77 percent were hormone-receptor positive and 13 percent were triple receptor-negative.
In those analyzed with HER2 positive tumors, the five-year, recurrence-free survival was 77.1 percent; in contrast, HER2 negative patients' recurrence-free survival was 93.7 percent. Five-year distant recurrence-free survival was 86.4 percent in
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| Contact: Laura Sussman lsussman@mdanderson.org 832-264-8893 University of Texas M. D. Anderson Cancer Center Source:Eurekalert |