Cancer Flashcards
What is cancer
Cancer is a disease caused by an uncontrolled division of abnormal cells in a part of the body
What is the difference between primary and secondary cancers
primary = arise directly from the cells in an organ Secondary = spread from another organ, directly or by other means
Where can GI cancers develop
Oesophageal Stomach Biliary system Pancreatic Colorectal - small intestine, large intestine, colon and anus
What are the two types of oesophageal cancer
Adenocarcinoma
Squamous cell carcinoma
Describe oesophageal adenocarcinoma
From metaplastic columnar epithelium Lower 1/3 of oesophagus Related to acid reflux (repeated epithelium damage) developed world males>females
Describe squamous cell carcinoma
From normal oesophageal squamous epithelium
Upper 2/3 of oesophagus
Acetaldehyde pathway (damages epithelial cells)
Less developed world
Asian population
What are the investigations done for colon cancer
Abdominal radiograohy (X-ray Plain computer tomography (CT) Barium Enema Colonoscopy CT virtual colonoscopy
Describe the epidemiology for colon cancer
more than 30,000 new cases a year
males>females
1/25 risk, 1/50 dying risk
What are the risk factors for colon cancer
Family History IBS Specific inherited conditions FAP, HNPCC, Lynch Syndrome Uncontrolled Ulcerative Colitis Age Previous Polyps
Describe pancreatic cancer and its symptoms
diagnosis is very late - “silent killer”
Symptoms include depression, abdominal pain and glucose intolerance
Later symptoms = weight loss, jaundice, ascites and gall bladder obstructions
What are the risk factors for pancreatic cancer
Smoking Drinking Obesity Family Especially rare conditions such as MEN
Describe the development of an adenocarcinoma
- Normal epithelium
- Hyperplasia - abnormal proliferation of epithelial cells
- Development of adenomatous polyps
- Development of adenocarcinoma
- Metastasis
Describe the development of a squamous cell carcinoma
- Normal epithelium
- Metaplasia - development of abnormal squamous cell (Barrett’s)
- Dysplasia - proliferation of abnormal cells
- Severe dysplasia - almost all cells are abnormal
- Development of squamous cell carcinoma
- Metastitsis
What are the associations and causes of adenomas and squamous cell carcinomas made
adenoma = obesity, tobacco smoking, alcohol consumption
SC carcinoma = tobacco smoking/chewing, alcohol consumption, ingestion
What are the symptoms for oesophageal cancer
do not appear until >50% is cancerous
early = difficulty and pain swallowing, weight loss, pain in the breast bone and stomach
late = nausea, vomiting, regurgitation, vomiting blood
What are the clinical investigations done for oesophageal cancer
Endoscopy - using a camera to observe the tumour, and a biopsy to evaluate the cells by histology
CT scan to check for metastasis
Endoscopic ultrasound to determine level of invasion
Describe the treatment for oesophageal cancer
Surgery
In early stages, the tumour may be removed from the oesophageal wall
Oesophagectomy - removal of part of the oesophagus
Chemotherapy and radiotherapy
What are the causes of colorectal cancer
Old age Diet (Red and processed meat) Alcohol Obesity Tobacco smoking Sedentary lifestyle
How is colorectal cancer screened for
Faecal sample to test for the presence of blood
Every 2 years for people >60
What are the symptoms of colorectal cancer
Worsening constipation Blood in the stool Loss of appetite Loss of weight Nausea and Vomiting Rectal bleeding Anemia
Describe the treatment for colorectal cancer
Surgery - remove the tumour via colonoscopy or laparotomy
Chemotherapy or radiotherapy
What is the pathology of adenocarcinoma
Not a single gene process
Sequence of genetic errors - APC
Which symptoms are NOT associated with colorectal cancer
Rectal bleeding (itch, soreness, external lump, prolapse) Change in bowel habit tp harder or less frequent stool Abdominal pin
What are the advantage and disadvantages of colonoscopy
advantages - safe, relatively quick, high sensitivity
disadvantages - bowel prep -
> diarrhoea
small risk of perforation
Risk of dehydration
