Lower GI oncology- Small bowel/instestine

Question 1

What are the layers of the GI tract?

Answer 1

Mucosa - consists of startified squamous epitheliium in mouth pharnyx oesophagus and anus. and then simple columnar epitheluim in the stomach and intestines (Adenocarcinoma)

Submucosa - connective tissue that includes blood and lymphatics

Muscularis - smooth muscle, peristalsis

Serosa

Question 2

What is the plica.

Answer 2

On the plica is VILLI

On the villi is MICROVILLI. Increased surface area good for absorption

Question 3

What is the drainage of the GI tract?

Answer 3

Superior mesenteric nodes - drain a portion of the duodenum, jejeunum, illeum, appendix, ascending conolon and 2/3rds of the transverse

Inferior mesenteric - drains the distal end of the transverse colon, descending colon, sigmoid colon, rectum, anus

Question 4

How long is the small intestine?

Answer 4

On average about 7meters

Joins the stomach and large intestine

Question 5

What are the three parts of small intestine?

Answer 5

duodemum, jejunum, ileum

Question 6

What is some epidemiology about SMALL BOWEL CANCER

Answer 6

Accounts for less than 5% of all gastr-intestinal tumours

More maliginant lesions are found in the duodenum and jejunim (however less frwuqent)

More benign lesions occur in the illeum (adenoma and fibromas)

Cancers usually occur in proximal end as opposed to distal end

Question 7

What genetic factors pose a greater risk of getting small bowel cancer?

Answer 7

People with polyposis
Crohns disease
Gardner’s syndrome