Researchers from M. D. Anderson Cancer Center in Houston reported that women with HER2-positive breast cancers 1 cm or less in diameter that have not spread to the lymph nodes have nearly three times the risk of recurrence and more than five times the risk of metastasis five years after diagnosis compared with women with similar-sized HER2-negative tumours.

“We expected the risk of recurrence and metastasis in HER2-positive node-negative patients with small tumours to be higher than in women with HER2-negative tumours, but we didn’t expect the magnitude of this risk to be so high,” said lead author Ana M. Gonzalez-Angulo, MD, associate professor in the Department of Breast Medical Oncology at the University of Texas M. D. Anderson Cancer Center. “This elevated risk is unacceptable, and indicates that women with small HER2-positive node-negative breast tumours should be offered participation in clinical trials assessing anti-HER2 therapies, such as trastuzumab [Herceptin], or other adjuvant treatment.”

Dr. Gonzalez-Angulo and her colleagues reviewed records from 965 women diagnosed between 1990 and 2002 at their institution with breast cancers 1 cm or less in size that had not spread to nearby lymph nodes. They compared the rates of recurrence and metastasis among women with HER2-positive and HER2-negative breast cancers after a median follow-up of six years. In addition, samples from an additional 350 women with breast cancer from two other institutions were analyzed to validate their findings.

The investigators found that five years after diagnosis, 77.1 percent of the HER2-positive patients were free of recurrence and 86.4 percent were free of metastasis, compared with 93.7 percent and 97.2 percent of the HER2-negative patients, respectively. Compared with women who had HER2-negative tumours, women with HER2-positive tumours were 2.68 times more likely to experience a recurrence and 5.3 times more likely to experience metastasis. The results of the analysis of the breast cancers from other institutions were consistent with these findings.


Source: ASCO / Journal of Clinical Oncology

Report: “High Risk of Recurrence for Patients With Breast Cancer Who Have Human Epidermal Growth Factor Receptor 2–Positive, Node-Negative tumours 1 cm or Smaller,” Gonzalez-Angulo, A., et. al. University of Texas M. D. Anderson Cancer Center, Houston, TX.