Patients with cancer undergoing treatments that can cause dysphagia. Difficulty swallowing in cancer patients can be a short-term radiation side effect of a treatment, such as chemotherapy or radiation therapy to the throat or chest area.

Radiation therapy is one of the main treatments for head and neck cancer. The radiation doses used to kill cancer cells can also damage normal cells and cause side effects. Side effects of radiation therapy are cumulative. This means that the more courses of treatment done over time, the higher the risk of side effects.