0319 - Colorectal Cancer

Question 1

What is the epidemiology of bowel cancer?

Answer 1

Second most frequent diagnosis of cancer, and second most frequent cause of cancer death in Australia.

Generally occurs over the age of 50.

Risk rate of 1 in 12 to 85, 1 in 1,000 to 40.

Question 2

What are the risk factors for CRC?

Answer 2

Age >50

Family history (though 75% have no family Hx)

Personal history of CRC or polyps

IBD

Lifestyle (diabetes, alcohol, obesity)
Acromegaly

Question 3

What is the interplay between CRC and the microbiome?

Answer 3

Microbiome believed to be associated with sessile serrated polyps, which are strongly associated with CRC.

Strong interplay between genetics and microbiome.

Question 4

What are the clinical features of CRC?

Answer 4

Abdominal pain

Change in bowel habit

Rectal bleeding

Anaemia

Weakness

Weight loss

Question 5

How can you tell right-sided from left-sided CRC?

Answer 5

Right sided - liquid stool, iron deficiency anaemia (occult bleeding)

Left Sided, colicky lower abdominal pain, constipation, formed stool, frank blood.

Question 6

How can CRC be diagnosed?

Answer 6

Screening

Masses, palpable liver (mets), or lymphadenopathy

COLONOSCOPY

Question 7

How does CRC develop?

Answer 7

Adenoma-carcinoma sequence.

Adenomatous polyp is more likely to be carcinogenic with size.

Polyps progress to cancer over 10-20 years.