Colorectal carcinoma

Question 1

Define colorectal carcionomas

Answer 1

Colorectal cancer-one of most common cancers in the world-mostly adenocarcinomas, 71% in colon (29% In rectum)

Dukes system-
A-mucosa limited
B1-3 (not through mucosa propria, through serosa no lymph nodes, tumour in adjacent tissue)
C1-3 (Same as B1-3 with metastatic nodes)
D-distance metastais

Question 2

Aetiology and risk factors of colorectal carcinoma

Answer 2

Complex genetic and environement factors (obesity, smoking)
usually starts with dysplastic adenomatous polyps (with loss of tumour suppression genes)-> develop to dysplasia, then cancer, then invades, most commonly liver

Risk factors:
Very rare before 40

Women have more proximal cancers, and men distal
FAP mutation
IBD
obesity

Question 3

Epidiemology of colorectal carcinoma

Answer 3

3rd most common cancer in the world, 4th leading cause of death
very rare under 40, age adjusted-187in 100000
decreasing in incidence

Question 4

Signs and Sx of colorectal carcinoma

Answer 4

AGE
rectal bleeding
change in bowel habits
Rectal mass
FLAWS

Unexplained anaemia in men over 40
abdo pain
weight loss
abdo distention
lymph nodes

Question 5

Investigations of colorectal carcinoma

Answer 5

ALWAYS investigate unexplained anaemia in en over 40—> colonoscopy
FBC-aneamia
Liver, renal-nromal (until liver metastases)

colonoscopy-lesion in the bowel lumen-take biopsies
CT colonoraphy