The overall aim of this research project is to get essential knowledge on late effects of radiation, particularly following Radiation Therapy, as well as an overall view of the radiotherapy process. The main goal of radiotherapy is to eradicate the tumour without damaging the healthy tissue. In practice, the high doses involved for killing the tumour cells, imply a certain risk that the healthy tissue around the tumour is also damaged.The proposed methodology for this project involves retrospective studies of patients treated earlier with radiotherapy. Due to the generally long-term follow up of patients in Sweden the basis for such an investigation is good. The project includes several practical parts such as re-examining old dose plans and even making new dose calculations where necessary, investigating and comparing different treatment techniques, making radiobiological conclusions and performing statistical analysis. By collaborating with clinical scientists on these issues, the PhD student will also benefit from the gained scientific experience. From all these points of view, this project is an ideal threshold for future work in a radiotherapy department.At present there is no radiotherapy treatment in Mozambique (although one treatment unit is planned) and therefore the study must be based, at least in the first stage, on data from the Swedish partners. This involves the need for access to data for patients treated at Radiumhemmet including the relevant treatment plans. It is also necessary to get access to the follow-up register, Karolinska Institute and Hospital has a good infrastructure for radio-therapeutic, radio-biologic and epidemiological studiesIn terms of investments in new equipment needed, this project requires access to a computer with relevant software for handling and reporting the data. It also requires access to treatment planning units and radiation measurement systems for dose reconstruction and measurement. This latter equipment already exists at the Swedish partners and therefore it does not require new investment.The dissemination potential of this project is quite important as it will provide personnel in Mozambique with the necessary skills in radiobiology connected with radiotherapy or radiation protection, It is estimated that the skills will also have good potential for practical use in the planned radiotherapy section in Mozambique.