Flashcards in New posters/review posters 22/05/2016 Deck (32):
What is a polyp?
A protrusion above an epithelial surface. It is a tumour (swelling)
Describe the shapes polyps can arise in?
Penduncle- has a neck
Sessile- hairy looking and lumpy
Benign polyps of epithelia
Peurtz Jeghers syndrome
Malignant polyps of epithelia
Benign polpys of mesentary
Malignant polyps of mesentary
The differential diagnosis of polyps
Dysplastic epithelial lining- not invasive and do not metastasise.
Described as pre- malignant- easily develop from normal mucosa to adenoma and then on to adenocarcinoma.
Treatment of adenoma polpys
Must be removed immediately because of pre-malignancy.
This is done endoscopically or surgically.
Treatment of adenocarcinoma polyp
Surgical- colon/rectum is removed and sent for pathological staging
Staging of polyps
Dukes A- confined by muscularis externa
Dukes B- through muscularis externa
Dukes C- metastatic to lymph nodes.
Familial adenomatos polyposis (FAP) or hereditary non-polyposis coli (HNPCC)
Familial adenomatous polyposis
Autosomal dominant. Early onset. Defect in tumour suppression gene (inherited mutation in FAP gene).
Pathology of FAP
occurs throughout colon. Adenocarcinomas. No specific inflammatory response. Associated with desmoid tumours and thyroid carcinomas.
Hereditary non-polyposis coli
Autosomal dominant. Late in onset. Defect in DNA mismatch repairin MLH 1 gene (other genes also).
Pathology of non-polpysis coli
Mucinous tumours. Crohns like inflammatory response. Associated with gastric and endometrial carcinomas.
Genes associated with cell cycle.
Oncogenes- Promote cell growth. When mutated- excess cell growth.
Tumour suppressor genes- suppress cell growth and division. When mutated- stop suppressing.
TNM staging of colorectal carcinoma
T1- submucosa only
T3- through muscle
N1= 3 nodel involved
N2 >3 nodes involved
Lifestyle adjustments for colorectal carcinoma
Protective foods- fibre, vegetables.
Causative things are- alcohol, smoking, obesity, processed/red meat.
Pre-disposing conditions for colorectal carcinoma
Clinical features of a carcinoma in the ascending colon
Anorexia and weight loss
Clinical features of a carcinoma in the descending colon
Pain, change in bowel habit and rectal bleeding
Clinical features of a carcinoma in the sigmoid colon/rectum
General symptoms of colorectal carcinoma
Cachexia (weakness and fatigue).
Mass may be palpable
Investigations into colorectal carcinoma
Faecal occult blood test
In the community- screening occurs by?
Every two years- 50-75 years olds are screened using a home FOBT
Emergency presentation of colorectal carcinoma
Obstruction- presents as abdominal distension, constipation, pain and vomiting
Bleeding or perforation.
Treatment of obstruction
Resection plus colostomy
Resection plus anastomosis
Treatment of colonic cancer (surgical)
iIn the abdomen:
In the rectum
Treatment of colonic cancer (radiotherapy)
Generally add on therapy
Could be used pre or post op.