In a nutshell
This paper reviewed treatments for human epidermal growth factor receptor 2 positive (presence of HER2, a protein on cancer cells) breast cancer that has metastasized (spread) to the brain.
Some background
Human epidermal growth factor receptor 2 (HER2) is a receptor that can be found on cancer cells. HER2 positive breast cancer tends to metastasize to the brain, affecting survival. Thus it is important to develop treatments to prevent or treat brain metastasis. Trastuzumab (Herceptin) is a drug that targets the HER2 and prevents cancer from growing.
Methods & findings
A recent report suggested that treatment with drugs targeting HER2 such as trastuzumab and the drug docetaxel (Taxotere) can delay tumour progression to brain metastases. Reviews showed that targeting HER2 with lapatinib (Tyverb) and capecitabine (Xeloda) can prevent disease from worsening and also reduce metastatic cancers of the brain.
It is important in treatment that drugs are able to cross the blood brain barrier (barrier that only allows certain substances to enter the brain). As yet, the ability of trastuzumab to cross the blood brain barrier is unknown. Hence, it is important to consider other methods of treatment.
One such drug that targets HER2 and is able to pass through the blood brain barrier is lapatinib. Experiments with lapatinib suggest it has potential, and should be further studied. Another way to bypass the blood brain barrier is to administer trastuzumab intrathecally (drug directly pumped to spinal cord or brain). A study found that intrathecal administration of trustuzumab and rituximab (Rituxan, Mabthera) benefitted patients with brain metastases of breast cancer.
A new technique being studied is the use of neural stem cells (cells that can potentially become cells of the nervous system). In animals, these cells could effectively reduce the size of the brain metastases and prolong survival.
The bottom line
The authors concluded that further research is important to develop treatments for brain metastasis.
Published By :
Cancer Letters
Date :
Dec 18, 2014
