A Reduced Variable Neighbourhood Search Algorithm for the Beam Angle Selection Problem in Radiation Therapy

Intensity-modulated radiation therapy (IMRT) is one of the most widely used techniques in radiation therapy for the treatment of many types of cancers. The main objective is to obtain a treatment plan that allows to eliminate the cancerous cells of the tumour and, at the same time, damage the organs at risk (OAR) around the tumour as little as possible. Beam Angle Optimization resolution techniques, such as reduced Variable Neighborhood Search (rVNS), are expected to be able to combine exploration and exploitation to accelerate the search for the best Beam Angle Configuration (BAC ). We have found an advantage over algorithms from the literature that we try to exploit through the proposed rVNS algorithm, combining different strategies to reduce the number of evaluations.