What Is Radiotherapy and Its Types?

What is radiation? Radiation is one of the spectra of electromagnetic energy, such as light, radio waves, and X-rays. X-rays can penetrate the body and interact with its atoms to varying degrees depending on the density of the organ, reflecting an image of what is inside the body — which is what happens in diagnostic CT scans. However, if the density and energy of these rays increase, they become destructive to cancer cells. History of radiation therapy X-rays were discovered by the physicist Wilhelm Röntgen in 1895. He discovered these invisible rays that penetrated his wife's hand, revealing the details of her hand bones without any pain. A year later, an enthusiastic medical student named Emil Grubbe thought of directing these rays at high intensity at a tumor in a breast cancer patient whose tumor had returned after surgery — the tumor responded and receded. This marked the beginning of radiation therapy, which became the third cornerstone of cancer treatment alongside traditional surgery and drugs. Types of radiotherapy The classification depends on how radiation is delivered to the patient, through two methods: 1) External-beam radiotherapy: usually using an electrical device called a linear accelerator, where radiation is directed at the patient with no direct contact between the radiation source and the patient — the most common. It has two forms: photon therapy (the most widely used, highly reliable with well-known results) and particle therapy, which is divided into electrons (for superficial tumors) and protons (for deep tumors). 2) Internal radiotherapy (brachytherapy): where a radioactive source is placed near or inside the tumor.