Chapter 24 - Use of neuro-imaging for radiation therapy planning

Abstract

Intracranial tumours are a diverse group of malignancies that can generally be classified as primary (originating from the brain) or secondary (metastases from other organs). The overall incidence of all primary intracranial malignancies is 21.03 cases per 100,000 individuals in the US from 2006 to 2010, which reflects international trends. The largest histological category of primary brain tumours are the gliomas, which have an incidence of 6.02 cases per 100,000 individuals in the US. The preferred treatment modality for benign tumours in general is surgical resection, with less frequent use of radiotherapy or chemotherapy. For malignant intracranial tumours, multi-modality treatment is frequently used, which includes systemic therapy and radiotherapy. The goal of radiotherapy for intracranial tumours is to eradicate gross and microscopic disease, while limiting normal tissue toxicities. Different radiation modalities are used including fractionated external beam radiation therapy, stereotactic radiosurgery and proton beam irradiation. We will review the imaging modalities used for intracranial tumour delineation and their role in radiation planning.