How does radiotherapy help brain tumor?

My sister-in-law has been having chemo for liver cancer, but now has a brain tumor as well and is getting radiotherapy for it. How does radiotherapy help?

Radiotherapy is the same as radiation therapy. Gamma knife, cyber knife and proton beam therapy are all forms of radiotherapy.

Radiotherapy is not a cure for a brain tumor. It can stop tumor growth or shrink it by stopping the blood flow to the tumor.

The way it works is, radiation beams are aimed from several angles to intersect at the tumor, delivering a large dose of radiation directly at the tumor. The radiation beams can be shaped to travel around normal healthy tissue like optic nerves and major arteries.

The blood-brain barrier (BBB) protects the brain from chemicals in the blood, so chemotherapy has no affect on brain tumors. That is why she needs the radiotherapy in addition to chemo.

Radiation has the ability to kill cancer cells, or at least put them in a state that they do not divide so fast.

Radiation Therapy uses high energy x-rays to kill cancer cells or to control growth of the tumor or to relieve symptoms.Radiation works by damaging the cancer cells ability to multiply.The health tissue around the tumor can repair itself.Usually,the whole brain is treated with careful consideration to make sure the eye is blocked out of the radiation.Treatments are usually Monday through Friday
with the total number of treatments can be as short as 10 or as many as 20 for metastatic disease.Sometimes if there are only a few small tumors,radiosurgery,gammaknife or cyberknife can be used,These techniques deliver high amounts of radiation directly to the tumor but,the tumor must be small.Side effects are minimal with hair loss,skin irritation,and fatigue most common.

My Dad tried GammaKnife for hsi brain tumor,
it was great results..........
His fine know.
I hope your sister will be fine too.
*/ Pray to Virgen Mary she help a lot too......................