Radiation induced oesophageal injury, or oesophagitis, is inflammation of the mucosal lining of the oesophageal wall. This can occur within the radiation field for treatment of tumours involving the thoracic region, such as the oesophagus, lung and mediastinum and some treatments to the head and neck. Breast patients receiving treatment to the supraclavicular fossa may experience mild oesophagitis; however, this is unlikely to have long term effects.
Oesophagitis may be a dose limiting toxicity, especially when administered with concurrent chemotherapy. This may compromise the patient’s fluid balance and nutritional statusrrr and can result in hospitalisation, interruption to treatment, invasive diagnostic tests or surgical intervention.r
The pathophysiology of radiation induced oesophageal injury is categorised as either acute or late.r Acute oesophagitis is an inflammatory response primarily affecting the basal epithelial layer of the mucosa.r Treatment induced cell death decreases the renewal rate of the basal epithelium. This causes mucosal abrasion and ulceration, with the potential to progress to the removal of the surface layer or denudation.rr Late radiation oesophagitis is primarily related to infiltration of fibroblasts and inflammatory cells into the muscle layers. This can cause changes to the muscle wall, although mucosal changes may also be observed.r
Late complications of radiation oesophageal injury may include oesophageal dysmotility, stricture, fibrosis, chronic ulceration, tracheoesophageal fistula and rarely, bleeding from chronic ulceration/perforation.rrr
Acute oesophagitis is a common toxicity of radiation therapy. Incidence varies depending on tumour location and irradiation volume. Incidence is also significantly increased in patients treated with concurrent chemotherapy or hyperfractionation.rrr
A study of patients with non small cell lung cancer (NSCLC) treated with concurrent chemoradiotherapy reported oesophagitis of any grade in 93% of patients, 45.1% of whom had grade 2 or higher reactions.r In a recent meta-analysis of 1082 patients with NSCLC receiving concurrent chemoradiotherapy, the incidence of clinically significant radiation oesophagitis (grade >2) was similar and reported in 50.2% of patients.r
A meta-analysis of advanced oesophageal cancer patients treated with concurrent chemoradiotherapy 25.6% of patients reported grade 2 or higher oesophagitis.r Patients being treated for head and neck malignancies are also at a significant risk of developing radiation induced oesophagitis.r
Onset of acute oesophagitis typically occurs two to three weeks after radiotherapy begins,r and may continue to worsen over the course of treatment. Acute symptoms should resolve within two to three weeks of treatment completion.r The majority of patients are able to maintain adequate oral intake, however a percentage of patients treated with radiotherapy for cancer of the lung, oesophagus and head and neck may require a feeding tube.r
Late toxicities can continue on from the acute phase or manifest after a latent period and may be ongoing.
The development and severity of oesophagitis is dependent on:rrr
- radiation dose and fractionation,
- concurrent chemotherapy,
- pre-existing dysphagia,
- increasing nodal stage,
- the volume of the oesophagus within the treatment field (circumference being more important than length),
Oesophagitis can occur earlier in patients with existing conditions such as previous oesophageal surgery, gastro-oesophageal reflux disease (GORD) and infection.r Patients older than 70 years of age are more likely to experience oesophagitis when compared with those under the age of 70.r