Study finds risk of recurrence low in smallest HER2+ breast cancer tumors

June 2, 2014

Patients with specific HER2+ breast cancer tumors had a low risk of the cancer recurring five years after diagnosis, even without chemotherapy or treatment with a common antibody, according to a Kaiser Permanente study published in the Journal of Clinical Oncology.

Researchers reviewed 16,975 cases of diagnosed in Kaiser Permanente patients between 2000 and 2006. They found that for patients with the smallest HER2+ tumors (0.5 centimeters or less) who did not receive treatment with the antibody trastuzumab or chemotherapy, the chance of surviving five years without a distant recurrence (cancer that spreads outside the breast to other organs) was 99 percent. A distant recurrence is considered to be more threatening than a local recurrence in the breast.

For patients with the next size (0.6 to 1 centimeter) the chance of surviving five years without a distant recurrence was 97 percent.

"Our results suggest that trastuzumab therapy may not be needed for patients with HER2+ tumors that are 0.5 centimeters in size or smaller, but should be considered for patients with larger tumors, with stronger consideration as the tumor size nears 1 centimeter," said lead author Lou Fehrenbacher, MD, medical director of Kaiser Permanente Oncology Clinical Trials and oncologist with Kaiser Permanente Vallejo Medical Center. "This is the first large study to demonstrate that the smallest lymph node–negative HER2+ breast cancers have a very low chance of returning."

Typical treatments for small, lymph-node–negative HER2+ tumors include surgery to remove the tumor and radiation therapy, although trastuzumab and chemotherapy are also frequently used to treat . HER2+ breast cancer, a subtype that accounts for between 15 and 20 percent of all cases of breast cancer in the United States, has been shown to respond well to trastuzumab. However trastuzumab can lead to heart failure in some women, particularly those who are older and who have other disease conditions.

Unlike larger tumors where distant recurrences are more common, the study found that the risk of local and distant recurrences was similar for these small HER2+ breast cancer tumors.

Explore further: Treatment targeting PI3K may delay resistance to anti-HER2 therapy in breast cancer patients

Related Stories

Study explains why drug may help more cancer patients

November 18, 2013

(Medical Xpress)—Recently some intriguing data has suggested that breast cancer patients whose tumors appear insensitive to a class of drugs known as anti-HER2 medications (the drug trastuzumab, marketed as Herceptin, is ...

Recommended for you

Combination therapy can prevent cytostatic resistance

November 26, 2015

Researchers at Karolinska Institutet have found a new way of preventing resistance to cytostatics used in the treatment of cancers such as medulloblastoma, the most common form of malignant brain tumour in children. The promising ...

Forecasting the path of breast cancer in a patient

November 23, 2015

USC researchers have developed a mathematical model to forecast metastatic breast cancer survival rates using techniques usually reserved for weather prediction, financial forecasting and surfing the Web.


Please sign in to add a comment. Registration is free, and takes less than a minute. Read more

Click here to reset your password.
Sign in to get notified via email when new comments are made.