13- Cancer Flashcards
2 types of oesophageal cancer and how they differ
Adenocarcinoma:
From metaplastic columnar epithelium
Lower 1/3 of oesophagus
Related to acid reflux
More developed world
Squamous cell carcinoma: From normal oesophageal squamous epithelium Upper 2/3 of oesophagus Acetaldehyde pathway Less developed world
How can colon cancer be investigated
Abdominal radiograohy (X-ray Plain computer tomography (CT) Barium Enema Colonoscopy CT virtual colonoscopy
5 risks for colon cancer
Family History Specific inherited conditions FAP, HNPCC, Lynch Syndrome Uncontrolled Ulcerative Colitis Age Previous Polyps
Pancreatic cancer outcomes
Generally, the outcome is poor and only 20% are suitable for a resection. Surgery is curative in 20-25% of cases; 1-year survival 18%, and 5-year survival 2%.
Pancreatic cancer symptoms
Early symptoms include depression, abdominal pain and glucose intolerance. Subsequent advanced symptoms include weight loss, jaundice, ascites and gall bladder obstructions.
5 stages of adenocarcinoma development
Normal epithelium Hyperplasia - abnormal proliferation of epithelial cells Development of adenomatous polyps Development of adenocarcinoma Metastasis
5 stages of squamous cell carcinoma development
Normal epithelium
Metaplasia - development of abnormal squamous cell
Dysplasia - proliferation of abnormal cells
Severe dysplasia - almost all cells are abnormal
Development of squamous cell carcinoma
Metastitsis
Causes of oesophageal squamous cell carcinoma
Main causes are tobacco smoking and chewing, alcohol consumption, and ingestion of caustic substances.
The link to alcohol is due to the acetaldehyde metabolite, which damages the epithelial cells.
Oesophageal adenocarcinoma causes
Related to acid reflux - repeated damage to the epithelium. Also associated with obesity, but due to unknown cause, tobacco smoking and alcohol consumption.
Symptoms of oesophageal cancer
Symptoms do not usually appear until a >50% of the circumference of the oesophagus is cancerous. This is due to the tumour narrowing the tube.
Difficulty and pain when swallowing
Weight loss - due to lack of nutrition
Pain in the breast bone and stomach, or a feeling of reflux
In later stages, further symptoms include:
Nausea, vomiting, and regurgitation of food
Vomiting blood, due to trauma to the tumour
Colorectal cancer causes
The main causes are old age, and lifestyle factors including diet (link to consumption of red meat and processed meat), alcohol, obesity, tobacco smoking and lack of physical activity.
