Early stage, HER2-positive breast cancer patients at increased risk of recurrence

December 12, 2008

This press release is available in Spanish.

SAN ANTONIO, TEXAS - Early-stage breast cancer patients with HER2 positive tumors one centimeter or smaller are at significant risk of recurrence of their disease, compared to those with early-stage disease who do not express the aggressive protein, according to a study led by researchers at The University of Texas M. D. Anderson Cancer Center.

The findings, presented today at the CRTC-AACR San Antonio Breast Cancer Symposium, is the first large study to analyze this cohort and represents a shift in the way women with early-stage HER2 positive breast cancer should be assessed for risk of recurrence and considered for treatment, said the study's senior author, Ana M. Gonzalez-Angulo, M.D, assistant professor in M. D. Anderson's Department of Breast Medical Oncology and Systems Biology.

Herceptin, also known as trastuzumab, was approved for use in 1998 for women whose advanced breast cancer expresses Human Epidermal growth factor Receptor 2, or HER2. Approximately 15-20 percent of breast cancer cells produce an excess amount of the HER2 growth protein on their surface, which makes the cancer more aggressive. Herceptin is a monoclonal antibody that latches on to these proteins and inhibits tumor growth.

"This study represents a current debate within clinical practice - the risk of recurrence for early-stage breast cancer patients with HER2 positive tumors one centimeter or smaller," said Gonzalez-Angulo. "Our findings show that women with early stage HER2 positive breast cancer have a 23 percent chance of recurrence. In contrast, the five-year survival rate of all women with such early-stage breast cancer is more than 90 percent.

"The findings indicate that physicians need to consider offering these women Herceptin-based therapy in the post-operative, or adjuvant setting," Gonzalez-Angulo continued.

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 women with HER2 positive tumors compared to 97.2 percent in women with HER2-negative tumors. Patients with HER2-positive tumors had 2.68 times higher risk of recurrence and 5.3 times higher risk of distant recurrence than those with HER2-negative tumors.

In addition, women with HER2-positive tumors had 5.09 times the risk of recurrence and 7.81 times risk of distant recurrence than women with hormone receptor-positive tumors.

The European subset confirmed the M. D. Anderson findings and showed reproducibility, said Gonzalez-Angulo.

"The risk of recurrence was much higher than we suspected. With this study, we now have concrete evidence to discuss with our HER2 positive patients with even the smallest of tumors, and Herceptin alone or combined with chemotherapy should be strongly considered as adjuvant therapy," said Gonzalez-Angulo. "This data should also encourage this subset of patients to be included in ongoing clinical trials with HER2-targeted therapies."

Gonzalez-Angulo hopes that a specific, three-arm clinical trial can be designed comparing observation, Herceptin, and Herceptin combined with chemotherapy.
-end-
The study was funded, in part, by an ASCO Career Development Award and NCI grant 1K23CA121994-01, both awarded to Dr. Gonzalez-Angulo, and by the Nellie B. Connally Breast Cancer Research Fund. In addition to Gonzalez-Angulo and Rakkhit, other M. D. Anderson authors on the study include: Gabriel Hortobagyi, M.D., Jennifer Litton, M.D., Vicente Valero, M.D., all of the Department of Breast Medical Oncology; Thomas Buchholz, M.D., Department of Radiation Oncology; Aysegul Sahin, M.D., Department of Pathology; and Funda Meric-Bernstam, M.D., Department of Surgery.

About M. D. Anderson

The University of Texas M. D. Anderson Cancer Center in Houston ranks as one of the world's most respected centers focused on cancer patient care, research, education and prevention. M. D. Anderson is one of only 41 Comprehensive Cancer Centers designated by the National Cancer Institute. For four of the past six years, M. D. Anderson has ranked No. 1 in cancer care in "America's Best Hospitals," a survey published annually in U.S. News and World Report.

University of Texas M. D. Anderson Cancer Center

Related Cancer Articles from Brightsurf:

New blood cancer treatment works by selectively interfering with cancer cell signalling
University of Alberta scientists have identified the mechanism of action behind a new type of precision cancer drug for blood cancers that is set for human trials, according to research published in Nature Communications.

UCI researchers uncover cancer cell vulnerabilities; may lead to better cancer therapies
A new University of California, Irvine-led study reveals a protein responsible for genetic changes resulting in a variety of cancers, may also be the key to more effective, targeted cancer therapy.

Breast cancer treatment costs highest among young women with metastic cancer
In a fight for their lives, young women, age 18-44, spend double the amount of older women to survive metastatic breast cancer, according to a large statewide study by the University of North Carolina at Chapel Hill.

Cancer mortality continues steady decline, driven by progress against lung cancer
The cancer death rate declined by 29% from 1991 to 2017, including a 2.2% drop from 2016 to 2017, the largest single-year drop in cancer mortality ever reported.

Stress in cervical cancer patients associated with higher risk of cancer-specific mortality
Psychological stress was associated with a higher risk of cancer-specific mortality in women diagnosed with cervical cancer.

Cancer-sniffing dogs 97% accurate in identifying lung cancer, according to study in JAOA
The next step will be to further fractionate the samples based on chemical and physical properties, presenting them back to the dogs until the specific biomarkers for each cancer are identified.

Moffitt Cancer Center researchers identify one way T cell function may fail in cancer
Moffitt Cancer Center researchers have discovered a mechanism by which one type of immune cell, CD8+ T cells, can become dysfunctional, impeding its ability to seek and kill cancer cells.

More cancer survivors, fewer cancer specialists point to challenge in meeting care needs
An aging population, a growing number of cancer survivors, and a projected shortage of cancer care providers will result in a challenge in delivering the care for cancer survivors in the United States if systemic changes are not made.

New cancer vaccine platform a potential tool for efficacious targeted cancer therapy
Researchers at the University of Helsinki have discovered a solution in the form of a cancer vaccine platform for improving the efficacy of oncolytic viruses used in cancer treatment.

American Cancer Society outlines blueprint for cancer control in the 21st century
The American Cancer Society is outlining its vision for cancer control in the decades ahead in a series of articles that forms the basis of a national cancer control plan.

Read More: Cancer News and Cancer Current Events
Brightsurf.com is a participant in the Amazon Services LLC Associates Program, an affiliate advertising program designed to provide a means for sites to earn advertising fees by advertising and linking to Amazon.com.