Context: 

The privately run Apollo Hospital said on Tuesday that it has treated up to 900 patients in its Chennai Based Proton Cancer Centre, and 47% of those cases are brain tumours.

About Proton Beam Therapy:

• Proton therapy is a type of radiation therapy which  uses protons rather than x-rays to treat cancer.
• A proton is a positively charged particle. At high energy, protons can destroy cancer cells. 
• Doctors may use proton therapy alone. They may also combine it with x-ray radiation therapy, surgery, chemotherapy, and/or immunotherapy.
• Like x-ray radiation, proton therapy is a type of external-beam radiation therapy. It painlessly delivers radiation through the skin from a machine outside the body.
• While radiation can prove toxic to the whole body, protons can destroy cancer cells precisely by targeting tumours, thus saving adjoining organs.
• Applications:

• • The PBT is considered a viable alternative to radiation for treating solid tumours, especially head and neck cancers.
  • Patients with cancers of the prostate, ovaries, breast, lungs, bones and soft tissues have also seen promising results in terms of recovery through the therapy.

Challenges in setting PBT centre

• Setting up a PBT centre is fraught with infrastructural and regulatory challenges stemming from safety concerns from the Department of Atomic Energy. 
• A PBT machine is a huge contraption, up to three storeys tall and costs nearly ₹500 crore.
• There are concerns of safety, as hydrogen is a highly volatile element and daily checks to prevent leaks have to be run.

                                                                                                                            News Source: The Hindu