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What Is Proton Therapy?

Protons are hydrogen atoms whose electrons have been removed. Proton beam radiotherapy uses a special machine called a cyclotron to energize protons. Protons are extracted from the cyclotron and directed with magnetic fields to the tumor. How deeply the radiation penetrates is calculated based on the tumor's location. Protons lose only a small amount of energy when they enter the body. Their remaining energy is released when they reach the tumor, delivering the most effective dose of radiation. Proton beams have no exit dose unlike conventional radiation therapy.

Proton beam radiation therapy is useful in treating a variety of cancers including:

  • Pediatric Cancers - such as:
    • astrocytomas
    • ependymomas
    • germinomas
    • medulloblastomas
    • optic gliomas
    • primitive neuro-ectodermal tumors
    • rhabdomyosarcomas
    • sarcomas
  • Head & Neck Cancers
  • Brain and Cranial Base Tumors - such as
    • acoustic neuromas
    • arteriovenous malformations (AVMs)
    • ependymomas
    • gliomas
    • meningiomas
    • pituitary adenomas and
  • Tumors of the eye and orbit - such as
    • ocular melanomas
    • retinoblastomas
  • Sarcomas
  • Prostate Cancer (early stage)
  • Spine Tumors - such as
    • Chordomas
    • chondrosarcomas
  • Thoracic Cancers
  • Gastrointestinal Cancers - such as
    • Liver tumors (unresectable)

Read more about Proton Therapy Treatment Options >>>

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