Modern radiotherapy techniques

Abstract

The aim of this review article is to present new sophisticated techniques in radiotherapy, which occurred due to the advancement of technology over the past few decades. The paper will provide insight into their advantages and disadvantages, the importance of diagnostic imaging modality, precise contouring, treatment planning and control of patients' position during radiation treatment. The transition from two-dimensional to three-dimensional radiotherapy has allowed contouring of target volume and organs at risk and accurate information on radiation dosage delivered. With a further desire for more precision and protection of healthy tissues, techniques such as intensity modulated radiotherapy (IMRT) and volumetric modulated arc therapy (VMAT) have been developed with the ability to modulate beam intensity. Quality imaging diagnostics is an infallible part of the modern radiotherapy. Image-guided radiotherapy (IGRT) and adaptive radiotherapy enable the delivery of high precision radiation to the target volume and spares organs at risk by correcting interfractional and intrafractional variations. Respiratory gating and tracking technique are useful for tumours that change their position during respiratory cycle. Stereotactic ablative radiotherapy (SABR) is a technique that uses highly conformal high-dose hypofractionated radiation to treat small tumours. In some indication such as the treatment of early stage non-small lung cancer, it competes with radical surgery. SABR is also an important therapeutic modality in the management of oligometastatic disease. This paper will briefly discuss proton therapy and its unique physical properties.