Radiotherapy uses high energy waves similar to x-rays to destroy cancer cells.
Early stage cancer means your oesophageal cancer hasn't spread. You might have external beam radiotherapy for early stage cancer. External beam radiotherapy directs radiotherapy beams at the cancer from a machine.
For early stage oesophageal cancers, radiotherapy is usually combined with chemotherapy (chemoradiotherapy).
The radiotherapy team plans your external beam radiotherapy before you start treatment. This means working out the dose of radiotherapy you need and exactly where you need it.
Side effects tend to start a week after the radiotherapy begins. They can include feeling tired, a sore throat and mouth, and difficulty swallowing.
Most side effects gradually go away in the weeks or months after treatment. But some side effects can continue. Or you might notice some that begin months or years later.