The most common treatment options for oesophageal cancer in the UK is surgery; alternative treatments are radiotherapy and chemotherapy. Pembrolizumab is a type of immunotherapy, which works targeting specific proteins that stimulates an immune response that targets the cancer cells. It increases the body’s natural ability to identify and attack cancer cells. If licenced, pembrolizumab will offer an additional treatment option for patients with oesophageal cancer and prolong the time without cancer progression.