Lecture 28 Flashcards
What is the most common cancer in NZ?
Cancers of colon
What are the two main categories of tumours of the colon?
Benign: mainly polyps
Malignant: mainly adenocarcinomas
What are polyps?
A circumscribed growth or tumour which projects above the surrounding mucosa
What is needed to determine the nature of a polyp?
Biopsy to determine if neoplastic or nonneoplastic
What are the two types of non-neoplastic polyps?
Hyperplastic polyps
Inflammatory polyps
What are the properties of hyperplastic polyps?
Benign, usually asymptomatic, no malignant potential, small 3-6mm, common
What are the properties of inflammatory polyps?
Seen in inflammatory bowel disease, overgrowth, benign, pseudopolyps
What are adenomas?
Benign polyps with malignant potential (neoplastic polyps)
When do adenomas usually occur?
Most age over 50, M=F
Is familial prefisposition involved with adenomas?
YES
What can be seen in an adenoma?
Epithelial proliferation with variable degrees of dysplasia
What is meant by dysplasia?
Abnormal growth compared to the normal mucosa
What are the three types of adenomas? Describe them
Tubular adenomas: Most common, mostly tubular glands
Villous adenomas: Villous projections, often large and sessile
Tubulovillous adenomas: Mixture of above
What is meant by sessile?
Flatter base (no stalk)
What are the symptoms of polyps?
Most asymptomatic
May bleed, mucosal discharge
If larger, can cause altered bowel habit, bowel obstruction