2. AIM
To study about Proton Beam Therapy in treating tumours

3. INTRODUCTION
• Proton beam therapy, also called proton therapy, is an external beam radiotherapy
that uses a beam of proton to irradiate diseased tissue
• During treatment, a particle accelerator targets the tumour with a beam of protons
which damage the DNA of these cells and thereby causing their death
• When passing through tissue, a proton deposits increasing dose slowly until
reaching a sharp increase(Bragg peak) at its maximum depth of penetration,
eliminating exit dose
• Proton therapy is non-invasive and is carried out on a outpatient basis
• Useful in the treatment of cancers surrounded by critical structures like spinal
cord, base of skull, optic nerve, etc

4. BLOCK DIAGRAM
Proton
accelerator
Beam
transport
system
Gantry
Treatment
delivery
system

6. METHOD
• Currently 2 proton beam delivery methods are available :
1. Passive spreading
2. Active spreading
• In passive spreading technique, the proton beam is spread by placing scattering
material in its path
• In scanning beam technique, magnets deflect and steer the proton beam

8. PROCEDURE
• All tissues are made up of atoms, having a central nucleus and negatively charged
electrons orbiting around the nucleus
• When protons pass near electrons, it pulls them out of their orbits. This is called
ionisation

9. • This changes the characteristics of the atom and also character of the molecule
within which the atom resides
• Radiation damages DNA within the cells and hinders with its ability to divide or
proliferate
• Enzymes attempt to rebuild the injured areas of the DNA
• Both normal and cancerous cells go through this repairing process
• Cancer cells ability to repair molecular injury is inferior so sustains more
permanent damage and finally cell death
• This permits selective destruction of bad cells growing among good cells

10. GRAPH

11. COMPARISON

12. ADVANTAGES
• Fewer short and long term side effects
• Precise targeting of tumours and cancer cells
• Reduced likelihood of secondary tumours caused by treatment
• Can treat recurrent tumours
• Proven to be effective in adults and children
• Improved quality of life during and after treatment

13. DISADVANTAGES
• Limited availability
• Large investment cost
• High treatment cost

14. APPLICATION
Proton therapy is used to treat the following cancers :
• CNS cancers (chordoma, chondrosarcoma, malignant meningioma)
• Eye cancer (uveal melanoma, choroidal melanoma)
• Head and neck cancers (paranasal sinus, nasal, nasopharyngeal)
• Lung cancer
• Liver cancer
• Sarcomas of skull base and spine
• Benign tumours of brain
• Paediatric malignancies

15. CONCLUSION
• Proton therapy has been applied safely with encouraging results for toxicity and
survival
• More research is needed to understand the limitations and potentials of protons

16. REFERENCE
[1] S. Frisch and B. Timmermann, “The Evolving Role of Proton Beam Therapy for
Sarcomas”, Clinical Oncology, vol 29, pp. 500-506, 2017.
[2] V. Gondi, T. I. Yock and M. P. Mehta, “Proton Therapy for Paediatric CNS
Tumours”, Nature Reviews, 2016.
[3] W. P. Levin, H. Kooy, J. S. Loeffler and T. F. DeLaney, “Proton Beam Therapy”,
British Journal of Cancer, vol 93, pp. 849-854, 2005.
[4] S. A. Holgate, “Cancer’s Newest Nemesis Hits the UK”, Engineering &
Technology, 2016.