Thesis

FLASH Radiotherapy: Investigating how FLASH protects healthy organs from radiation toxicity

• Call:

  ProtoTera Call 2020

• Academic Year:

  2020/2021

• Supervisor:

  Joao Seco

• Co-Supervisor:

  Patrícia Gonçalves

• Host Institution:

  Division of Biomedical Physics in Radiation Oncology from the German Cancer Research Center, DKFZ

• Granting Degree Institution:

  Instituto Superior Técnico (Universidade de Lisboa)

• Typology:

  Mixed

• Abroad Institution:

  Instituto Superior Técnico (Universidade de Lisboa)

• Abroad Supervisor:

• Abstract:

  Rationale Radiotherapy has always been a trade-off between tumor control and organ toxicity, where healthy organs are in many cases very sensitive to radiation. However, after recent developments in FLASH radiotherapy, this paradigm has been challenged due to a significant reduction in the toxicity of healthy organs [1]. “FLASH” is based on very high dose-rate irradiation (dose rate ≥50 Gy/s), short beamon times (≤100 ms) and large single doses (≥10 Gy) per beam [1]. At the moment, it is still unknown how to apply clinically FLASH to treat patients. Recent clinical implementation of FLASH has focused on delivering a single beam with FLASH to treat cancers on the skin or in the extremities (hands and legs). Single beam doses above 10Gy to 12 Gy is not common in standard radiotherapy, because of the very high risk of radiation toxicity. At the moment it is still unknown how to perform FLASH with multi-beams. PhD Project Goals (G) G1: To study the FLASH effect using Monte Carlo tools such GEANT4, TOPAS, gMicroMC and TRAX-CHEM. The Monte Carlo tools will allow the evaluation of the chemical reaction of proton radiolysis. The PhD project will investigate how the chemical products of this reaction can produce FLASH protection in cancer cells and not in healthy cells. G2: To investigate how to implement multi-beam FLASH in proton radiotherapy using the treatment planning software MATRAD. G3: To investigate how FLASH can be used in combination with other delivery methods such 3D conformal radiotherapy (3D-CRT), intensity modulated radiotherapy (IMRT) and mini- or micro-beams, to maximize the theapeutic benefit. REFERENCES 1. Wilson et al (2020) “Ultra-high dose rate (FLASH) Radiotherapy: Silver bullet or fool’s gold?” Front. Oncol. 9:1563 doi:10.3389/fonc.2019.01563