Thema: Presse: HER2-positive breast cancer doubles risk of brain metastases
Presse: HER2-positive breast cancer doubles risk of brain metastases
Marion[a]
18.12.2005 16:02:57
HER2-Positive Breast Cancer Doubles Risk of Brain Metastases : Presented at SABCS
By Cameron Johnston
December 12, 2005
Women whose breast cancer over-expresses the HER2 oncogene have more than twice the risk of developing brain metastases compared with women who do not over-express HER2.
In a Scottish study presented at the 28th Annual San Antonio Breast Cancer Symposium (SABCS), Claire Paterson, MD, Senior Registrar, Glasgow Western Infirmary, Glasgow, Scotland, said all women with breast cancer in Scotland are now routinely screened for the presence of the HER2 gene, which is known to be associated with a more aggressive form of cancer.
Studies have suggested that women who are treated with trastuzumab (Herceptin) may be susceptible to brain metastases because the large molecule of the trastuzumab does not cross the blood brain barrier and therefore does not offer protection to that part of the body. Research has also been suggested that the fact these women appear to have more brain metastases is because the trastuzumab protects them longer from the breast cancer progressing throughout the viscera and therefore, there is more time for the brain cancer to develop.
In Dr. Paterson´s analysis, 100 women with confirmed brain metastases were screened and 60 were evaluated. They found that 57% were HER2-positive and the rest were HER2 negative. Of those who were HER2-positive, 22% were also estrogen receptor positive and 35% were estrogen receptor-negative.
The generally accepted rate of HER2-positivity in the breast cancer population is 20% to 25%, Dr. Paterson said, and yet in this study, more than half of the women who were HER2-positive developed brain metastases. She also noted that 41% of the women had not been exposed to trastuzumab and, therefore, the previous theories as to why these women develop brain metastases do not apply.
"These features suggest that brain metastasis is an intrinsic feature of the disease, and cannot be solely attributed to the fact that trastuzumab offers better systemic disease control," she said.
A more likely explanation for the spread of the disease in this way lies with a cytokine known as CXCr4, which facilitates the movement of the disease cells and is known to be over-expressed in HER2 positive cancer, she said. In breast cancer, and other cancers, CXCr4 has also been associated with poorer outcomes overall.
The findings warrant a larger prospective study, Dr. Paterson concluded.
[Presentation title: Does HER2 Positive Breast Cancer Have a Prelediction to Metastasise to the Brain? Abstract 4086]
By Cameron Johnston
December 12, 2005
Women whose breast cancer over-expresses the HER2 oncogene have more than twice the risk of developing brain metastases compared with women who do not over-express HER2.
In a Scottish study presented at the 28th Annual San Antonio Breast Cancer Symposium (SABCS), Claire Paterson, MD, Senior Registrar, Glasgow Western Infirmary, Glasgow, Scotland, said all women with breast cancer in Scotland are now routinely screened for the presence of the HER2 gene, which is known to be associated with a more aggressive form of cancer.
Studies have suggested that women who are treated with trastuzumab (Herceptin) may be susceptible to brain metastases because the large molecule of the trastuzumab does not cross the blood brain barrier and therefore does not offer protection to that part of the body. Research has also been suggested that the fact these women appear to have more brain metastases is because the trastuzumab protects them longer from the breast cancer progressing throughout the viscera and therefore, there is more time for the brain cancer to develop.
In Dr. Paterson´s analysis, 100 women with confirmed brain metastases were screened and 60 were evaluated. They found that 57% were HER2-positive and the rest were HER2 negative. Of those who were HER2-positive, 22% were also estrogen receptor positive and 35% were estrogen receptor-negative.
The generally accepted rate of HER2-positivity in the breast cancer population is 20% to 25%, Dr. Paterson said, and yet in this study, more than half of the women who were HER2-positive developed brain metastases. She also noted that 41% of the women had not been exposed to trastuzumab and, therefore, the previous theories as to why these women develop brain metastases do not apply.
"These features suggest that brain metastasis is an intrinsic feature of the disease, and cannot be solely attributed to the fact that trastuzumab offers better systemic disease control," she said.
A more likely explanation for the spread of the disease in this way lies with a cytokine known as CXCr4, which facilitates the movement of the disease cells and is known to be over-expressed in HER2 positive cancer, she said. In breast cancer, and other cancers, CXCr4 has also been associated with poorer outcomes overall.
The findings warrant a larger prospective study, Dr. Paterson concluded.
[Presentation title: Does HER2 Positive Breast Cancer Have a Prelediction to Metastasise to the Brain? Abstract 4086]
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