brain metastases from breast cancer treatment/chemotherapy options

My sister (47) was diagnosed with breast cancer (T3, ER+, PR+, HER2-) 4 years ago. She had radiotherapy, followed by mastectomy+radiotherapy and chemo with anthracycline, followed by tamoxifen.
October 2007 she was diagnosed with brain metastases (not operable). She was treated with radiotherapy and temodar, which initially had some effect, but then in July 2007 the metastases progressed and her left leg and arm were paralyzed.
She is currently taking CCNU (she had her second treatment a few days ago) and several natural supplements, including Boswellia Serrata (4,200 mg/day; CoQ10, melatonin, bromelain, low fat cottage cheese and flax oil and seeds) and she is on a low fat diet.  However, no much improvement has been noticed.
I would appreciate any advice/suggestion about treatments of brain metastases that could be relevant to my sister's case. What do you think about using xeloda, faslodex, letrosole (femara), or insulin potentiation therapy in the treatment of brain metastases from breast cancer?
It seems that a major issue is whether the drug crosses the blood brain barrier. However, it is known that in case of brain tumor/metastases the integrity of the blood brain barrier is compromised?

[Cleveland Clinic]

Dear winter09:  Brain metastasis can be a difficult problem to treat.  Without evaluation, it is impossible for us to speculate on the specifics of your sister's situation.  You might consider an opinion from a brain tumor specialist at a large center if this is a possibility.