Definition
Oesophagitis is the inflammation of the mucosal lining of the oesophageal wall.rrr This can occur during radiation therapy when the oesophagus is within the radiation field, e.g. in the treatment of tumours involving the thoracic region, such as the oesophagus, lung and mediastinum and some treatments to the head and neck.rr Breast patients receiving treatment to the supraclavicular fossa may also experience mild oesophagitis.
Pathophysiology
The pathophysiology of oesophagitis 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 Acute oesophagitis may be a dose limiting toxicity, especially when administered with concurrent chemotherapy. Oesophagitis may compromise the patient’s fluid balance and nutritional status and can result in hospitalisation, interruption to treatment, invasive diagnostic tests or surgical intervention.rrrr
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 oesophagitis may include oesophageal dysmotility, stricture, fibrosis, chronic ulceration, tracheoesophageal fistula and rarely, bleeding from chronic ulceration/perforation.rrr
Incidence/prevalence
Acute oesophagitis is a common toxicity of radiation therapy. Incidence varies depending on tumour location, irradiated volume and dose received. 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 chemoradiation therapy reported oesophagitis of any grade in 93% of patients, 45.1% of whom had grade 2 or higher reactions.r In a meta-analysis of 1082 patients with NSCLC receiving concurrent chemoradiation therapy, 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 chemoradiation therapy reported 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/duration
Onset of acute oesophagitis typically occurs two to three weeks after radiation therapy begins, and may continue to worsen over the course of treatment and peak in the 1-2 weeks following treatment completion.r Acute symptoms should resolve within two to three weeks of treatment completion.r
Late toxicities can continue from the acute phase or manifest after a latent period and may be ongoing. Although rare, narrowing of the oesophagus (oesophageal stricture) can develop months or years after treatment.rr
Risk factors
Risk factors for the development and severity of oesophagitis include:rrr
- radiation dose and fractionation
- concurrent chemotherapy
- co-morbidities e.g. existing dysphagia, previous oesophageal surgery, gastro-oesophageal reflux disease (GORD) and infectionr
- increasing nodal stage
- increasing volume of the oesophagus within the treatment field (circumference being more important than length)
- age >70 years.r