There were about 200,000 new cases of cancer in Thailand in 2020. Recent advances in the fields of surgical oncology, medical oncology, and radiation oncology have immensely improved the results of cancer treatment. Even with the best multidisciplinary treatment, in more than half of the patients, cancer will recur and require further treatment with the aim of palliation to improve the quality of life and hopefully prolong life. Radiation therapy is an important cancer treatment modality with curative intent or palliative aims. Modern advanced radiation therapy techniques make it possible to deliver high doses of radiation to the tumour while minimising the doses to surrounding normal tissue. As a result, tumour control in curative and palliative settings is far superior to that in the past.
Modern radiation therapy utilises a high-energy radiation beam to kill cancer cells whereas diagnostic radiology uses low-energy X-rays and dose. Radiation therapy can treat all types and stages of cancer, alone or in combination with surgery and chemotherapy, based on the type and stage of cancer. The combinations can be concurrent or given in sequences. There are two main types of radiation therapies: external radiation and brachytherapy.
