Colon cancer

Question 1

What is the tumour marker for colon cancer?

Answer 1

Carcioembyonic antigen (CEA)

Question 2

What are the three forms of colorectal cancer and how common are they?

Answer 2

Sporadic (95%)
Hereditary non polyposis colorectal cancer (5%)
Familial adomatous polyposis (1%)

Question 3

What is hereditary non polyposis colorectal cancer?

Answer 3

This is the most common form of inherited cancer

It is autosomal dominant and causes poorly differentiate, highly aggressive cancers of the proximal colon

Question 4

What criteria is used to determine the severity of HNPCC?

Answer 4

The amsterdam criteria

Question 5

How is familial adomatous polyposis usually managed?

Answer 5

Patients usually have a total colectomy in their 20s

Question 6

Where are the common locations in the colon for colorectal cancers?

Answer 6

Rectal 40%

Sigmoid 30%

Question 7

What is the screening programme for colorectal cancer?

Answer 7

All men and women over 60 to 74 will be send faecal occuclt blood tests through the post
This is every 2 years

Question 8

What abnormalitiy seen on colonoscopy is likely to cause cancer?

Answer 8

A polyp

Question 9

How should colon cancer be investigated and staged?

Answer 9

With a CT of chest/abdo and pelvis

Entire colon should be evaluated with colonoscopy or CT colography

Question 10

What is the treatment of coloic cancer?

Answer 10

Curative is resection, can bring out a stoma temporarily and then go back and try and create an anastomosis
Usually given adjuvant chemo

Question 11

What is the treatment of rectal cancer?

Answer 11

Typically an anterior resection and requires a 2cm margin

As the rectum is extraperitoneal it can have neoadjuvant radiotherapy