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What is IMPT?

Intensity-Modulated Proton Therapy (IMPT)

What is IMPT?

Intensity-modulated proton therapy (IMPT) is a highly precise type of radiation therapy using proton therapy. Intricate treatment planning and precise proton-beam delivery result in a modulation of the intensity of the proton beam and its shaping so that it matches the contours of the tumour. IMPT also provides the most-conformal dose-delivery technique for radiation therapy, 'coloring' the tumour precisely within the lines prescribed by the physician. It also produces significantly fewer neutrons than other types of proton systems, and therefore delivers less radiation to the healthy tissue adjacent to the tumour. This is especially important for pediatric patients who are at greater risk of developing neutron-induced secondary cancers later in life—and for patients with tumours that are in close proximity to critical structures that cannot be exposed to radiation.

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Beam Scanning Delivers True IMPT

Only Pencil-Beam Scanning Delivers True IMPT

Not all proton therapies can deliver IMPT, only Pencil-Beam Scanning (PBS) can. With its highly accurate targeting of tumours, IMPT focuses a narrow proton beam to 'paint' the radiation dose, spot by spot and layer by layer, onto all parts of a tumour—even irregularly-shaped tumours. IMPT is effective for tumours that wrap around critical structures (such as the brain or spinal cord) or that are located adjacent to structures or organs (e.g., the frequent proximity of prostate tumours to the bladder or large intestine, or of breast tumours to the heart).

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Mayo Clinic Proton Workshop
Scottsdale, AZ, USA
SCC AAPM Midwinter Workshop
Los Angeles, CA, USA
Arab Health Meeting 2019
Dubai, United Arab Emirates