According to the IAEA, a quick and reliable dose assessment is an essential part of radiation emergency management. Given the currently increased risk of terrorist attacks with the use of an improvised nuclear device but also of a nuclear war, it is important to develop dosimetric solutions for fast on-field application in case of a large nuclear emergency. The aim of this project is to carry out research aiming at improving dosimetric preparedness and competence in Sweden to cope with a large nuclear emergency. The project is divided into 3 complementary tasks: 1) to simulate the radiation field and map the equivalent dose distribution as a function of distance and shielding from an improvised nuclear device detonated in a urban environment; 2) to carry out a survey of the available dosimetry systems and identify the best suited one for quick in field application following a large nuclear emergency accounting for neutrons and gamma radiation; 3) to validate gene expression as an individual, quick retrospective dosimeter for a mixed neutron and gamma irradiation as expected following the detonation of an improvised nuclear device.

Proton radiotherapy is delivered in Sweden at the Skandion Clinic, the national proton radiotherapy centre run in collaboration with the seven Swedish university hospitals. The most commonly quoted advantage of proton therapy over photon therapy is the potential of reducing the deterministic toxicity in normal tissue and the organs at risk (OARs). This is based on the fact that proton treatment optimisation succeeds at producing plans that are ensuring good coverage of the target and steep gradients of the dose outside the target leading thus to a better sparring of the normal tissue and the organs at risk and therefore lower deterministic toxicity. This project aims at investigating and developing proton treatment planning optimisation approaches that would reduce both the deterministic toxicity and the stochastic effects for the same quality of the plan with respect to the target coverage minimising therefore the radiation protection concerns regarding proton therapy.

Ionising radiation is used increasingly for the treatment of cancer being the source of a considerable fraction of the artificial irradiation to the patient. With the increasing success rate of cancer treatments and longer life expectancies of the treated patients, the issue of secondary cancer incidence is of growing concern, especially for paediatric patients who may live long and be more susceptible to secondary cancers. Also, diagnostics imaging modalities like CT and PET due to repeated imaging sessions are the source of significant radiation exposure associated with higher risk of occurrence of secondary cancers. The aim of the research project is the assessment of secondary doses to healthy tissues that are delivered by the use of modern radiation therapy and diagnostics imaging modalities in the clinical environment. The work is also focused on the investigation of the risk of induction of secondary cancers associated with modern radiotherapy implying not only new irradiation techniques like IMRT and proton therapy but also additional radiation exposure due to repeated imaging sessions.