Leiomyomas are the commonest benign tumours. They are usually discovered accidentally and they do not often produce symptoms. Malignant These occur in the middle of the oesophagus and are squamous carcinomas. Adenocarcinomas occur in the lower third of the oesophagus and at the cardia. Kaposi’s sarcoma is frequently found in the mouth and hypopharynx in patients with AIDS . These tumours rarely lead to symptoms and consequently do not require treatment.
EPIDEMIOLOGY AND AETIOLOGICAL FACTORS
SQUAMOUS CARCINOMA. The incidence of carcinoma varies throughout the world, being high in China, parts of Africa and in the Caspian regions of Iran (where the incidence is the highest observed for any type of cancer anywhere in the world). In the UK it is 5-10 per 100000 and represents 2.5% of all malignant disease. The variation in incidence throughout the world is greater than for any other carcinoma and is unusual in that sharp differences occur in regions very close to one another. Dietary and other environmental causes have been looked for and it is probable that different causative agents are involved in different parts of the world. Carcinoma of the oesophagus is commoner in men and there is an increased incidence in heavy drinkers of alcohol as well as heavy smokers. Predisposing factors include Plummer- Vinson syndrome, achalasia, coeliac disease and the familialcondition of tylosis (hyperkeratosis of palms and soles).
ADENOCARCINOMA. These arise in the columnar lined epithelium of the lower oesophagus (Barrett’s oesophagus). This columnization results from long-standing reflux, although one-third of patients will have no preceding symptoms. This premalignant lesion increases the chances of adenocarcinoma 30-40 times. Extension of adenocarcinoma of the gastric cardia can cause oesophageal obstruction.
Carcinoma of the oesophagus occurs mainly in those aged 60-70 years. Dysphagia is the commonest single symptom and is progressive and unrelenting. Initially there is difficulty in swallowing solids, but eventually dysphagia for liquids also occurs. Benign strictures, on the other hand, initially produce intermittent dysphagia. Impaction of food causes pain, but more persistent pain implies infiltration. The lesion is usually ulcerative, extending around the wall of the oesophagus to produce a stricture. Direct invasion of the surrounding structures rather than widespread metastases occurs, and at presentation 50% have regional lymph node involvement. Weight loss, due to the dysphagia as well as to anorexia, frequently occurs. The oesophageal obstruction eventually causes difficulty in swallowing saliva, and coughing and aspiration into the lungs is common. Signs are often absent. Weight loss, anorexia and lymphadenopathy are occasionally found.
BARIUM SWALLOWis often the initial investigation. although many gastroenterologists like to go directly to oesophagoscopy which provides histological or cytological proof of the carcinoma; 90% of oesophageal carcinomas can be confirmed with this technique.
CT SCAN will show the volume of the tumour and also possible spread outside the oesophagus. It has been used to attempt to stage tumours prior to surgery, but results are disappointing.
ENDOSCOPIC ULTRASOUND has an accuracy rate of nearly 90% for assessing depth of tumour infiltration and 80% for staging lymph node involvement and is being increasingly used.
The overall results are poor (2% 5-year survival) and only symptomatic and palliative treatment is a realistic possibility in most cases. Dilatation of the stricture and the placing of a tube to keep the oesophagus open is the usual therapy and can be performed via an endoscope. Tumours can be photo coagulated using a laser beam directed through an endoscope or sloughed using alcohol injections. Both are useful to improve dysphagia.
Surgery carries a high morbidity and mortality, but in some series in which preoperative staging shows no spread outside the wall a 5-year survival rate of 25% has been achieved. Radiotherapy and chemotherapy can be used for squamous carcinoma with limited success. Good palliative care with support for the patient and family is vital in this distressing disease.