Indications for definitive chemoradiotherapy for oesophageal cancer

Oesophageal cancer is the ninth most common cancer diagnosed, and seventh most common cause of cancer-related deaths worldwide. Despite significant advances in imaging, surgery, radiotherapy and systemic therapy over the past few decades, treatment outcomes in patients with localised oesophageal cancer remain suboptimal with a 5-year overall survival of less than 50%. Current treatment guidelines recommend surgery with/without pre-operative chemotherapy or chemoradiotherapy for patients with localised resectable disease. Hence, definitive radiotherapy (with or without chemotherapy) has predominantly been reserved for those who are deemed unsuitable for surgery. The role of radiotherapy in definitive management of oesophageal cancer has been recognised since the 1960s. The addition of concurrent chemotherapy has shown to improve treatment outcomes and has remained standard of care since the RTOG 85-01 and Intergroup 0123 trials. This review discusses the current literature on definitive radiotherapy with/without chemotherapy for localised oesophageal cancer, and evaluates current radiation modalities and technological developments in radiotherapy planning and delivery. We will provide an overview on the literature for definitive chemoradiotherapy in oesophageal cancer, the epidemiological and treatment response differences between squamous cell carcinoma and adenocarcinoma of the oesophagus, followed by a review of the current literature on different radiation treatment modalities (intensity modulated radiotherapy, brachytherapy and proton therapy) and the use of different imaging modalities for radiation treatment planning.