Correct answer:

The subjective site of obstruction is not always exact; the patient often merely points vaguely to behind the sternum. The diagnosis may be given by a history of swallowed caustic in the past. A previous story of reflux oesophagitis suggests a peptic stricture. Patients with achalasia tend to be young and the history is often long, usually without loss of weight. Malignant stricture has a short history, occurs in elderly people and is associated with severe weight loss.