- Sharp beam, negligible penumbra (precise radiation delivery to the tumour, avoiding the surrounding normal tissues)
- High energy, penetrating beam, that spares skin and subcutaneous tissue, bladder, rectum, etc.
- Wide range of electrons (6 MeV to 21 MeV) Releasing energy at desired depth e.g. skin to 6 cm. and sparing underlying structures.
- Tumours near critical organs e. g. brain, eyes, spinal cord, lung, heart, kidney, rectum, head and neck malignancy, etc.
- Obese patients and deep seated tumours e.g.
- Thoracic: lung tumours, mediastinal nodes.
- Abdominal: abdominal nodes, kidney, gall bladder fossa, etc.
- Neck nodes over spinal cord
- Chest wall over lung in breast cancer patients after mastectomy
- Re-irradiation i.e. radiation in recurrent tumors previously treated with RT.
- Thoracic or abdomino-pelvic cancer over critical organs