CARCINOMA OF OESOPHAGUS (Robbins pp 783)

The most common type of cancer affecting the oesophagus is of epithelial origin.

Incidence

Accounts for about 2-3% of all malignant tumours in Scotland, and is the commonest cancer in China, Iran, Russia, and South Africa. Diagnosis is usually late, therefore prognosis is poor.

Two main types: Squamous cell carcinoma, adenocarcinoma of oesophagus

Aetiology of both types of carcinoma

Aetiology can be put down to the following categories: dietary, lifestyle, oesophageal disorders, genetic predisposition. Dietary factors include: nutritional deficiencies such as≫vitamins, zinc, fungal toxins in foodstuffs, nitrites/nitrosamines. Lifestyle factors include: alcohol & tobacco usage. Oesophageal disorders include: long-standing oesophagitis (due to high turn over of epithelial cells therefore more chances of mutations), Barrett’s oesophagus. Genetic predisposition: blacks are affected more than whites.

Macroscopic appearance of both types of carcinoma

Most cancers occur midway along the oesophagus. Initially, they appear as mucosal thickenings. After a while, they can progress to any of the following three pathways: 1) protruded lesion: a polypoid lesion that protrudes into the lumen therefore causing obstruction, 2) diffuse spread: the lesion spreads along the internal surface of the oesophagus, eventually encircling the lumen ≫ making the walls rigid and thickened, 3) excavated: where they ulcerate into the oesophageal wall and go through it.

Microscopic appearance of both types of carcinoma

By the time of diagnosis, both types of cancers usually have spread into the wall of the oesophagus..

Complications of Ca of oesophagus

• Spread: If the lesion is ulcerative, then it can spread to posterior mediastinum, pleural cavity. Most of the times the spread is via lymphatics as the oesophagus has lots of lymph vessels in its submucosa. Metastases can occur to cervical, paratracheal, tracheobronchial, and coeliac lymph nodes respective to where the lesion is present.

• Obstruction: If the lesion is diffuse or polypoid, it can produce stenosis or total obstruction of the lumen. This can cause food material to reflux back into the respiratory tree – causing aspiration pneumonitis

• Inanition: A cancer of any sort will starve the human body ≫ leading to weight loss, appetite loss etc.

Other types of tumours in oesophagus

Other types of tumours include: Benign (leiomyomas, fibromas etc). Malignant variety include: malignant melanoma (oesophagus contains some melanocyte) etc.

Category: Pathology Notes