Lower GI Mcq

Question 1

What proportion of colorectal cancers develop via chromosomal instability pathways?

Answer 1

85%

Question 2

A patient presents with numerous small polyps covering the colonic mucosa. Additional investigations reveal osteomas of the skull, a periampullary adenocarcinoma, and epidermal inclusion cysts. What condition is this patient most likely to have?

Answer 2

Gardener’s syndrome

Question 3

Why is a pre-operative MRI vital for rectal cancers?

Answer 3

To accurately assess the depth of invasion and nodal involvement

Question 4

Which molecular marker is often used to guide treatment decisions in stage 4 colorectal cancer?

Answer 4

KRAS gene

Question 5

What is the definition of early rectal cancer according to the sources

Answer 5

T1-2, N0, well-differentiated, < 2 cm

Question 6

What is the preferred treatment approach for borderline resectable rectal cancer?

Answer 6

Pre-operative chemo radiation therapy followed by surgery then post op chemo .

TNT approach

Question 7

What term is used to describe a surgical procedure where part of the colon is removed and the remaining ends are joined together?

Answer 7

lower anterior resection (LAR)

Question 8

What is the surgery that requires the removal of the rectum, anus, and surrounding tissues, including the mesorectum. Resulting in the requirement of a permanent colostomy (opening in the abdomen where faeces are collected in a bag)

Answer 8

Abdominal perineal resection

Question 9

What surgery is the removal of the affected portion of the rectum creating a temporary colostomy. Remaining colon is closed off and may be reconnected to anus

Answer 9

Hartmann’s procedure

Question 10

What is the surgical technique that involves the removal of the rectum, the mesorectum, and a section of the bowel above and below the tumour

Answer 10

Total mesorectal excision

Question 11

What is the main benefit of using Intensity-Modulated Radiation Therapy (IMRT) for anal cancer, compared to 3D conformal radiotherapy (3DCRT)?

Answer 11

Reduced toxicity

Question 12

What is the proximate 5 year overall survival rate for patients with negative node involvement in anal cancer

Answer 12

80%

Question 13

What is the proximate overall survival rate for patients with Inguinal node involvement in anal cancer

Answer 13

50%

Question 14

What is the proximate overall survival rate for patients with pelvic node involvement in anal cancer

Answer 14

30%

Question 15

What is the expected local control and organ sparring in anal cancer

Answer 15

Local control: 80%
Organ sparing: 70-80%

Question 16

What are the benefits of TNT for rectal cancer

Answer 16

Reduced toxicity
Improved local control
Increased chance of organ preservation

Question 17

What is the role of radiotherapy in the treatment of metastatic colorectal cancer

Answer 17

Used for palliation and local control

Question 18

What percentage of colorectal cancers are estimated to be caused by defective DNA mismatch repair characterized by MSI (microsatilite instability)

Answer 18

15%

Question 19

What does the denate line indicate

Answer 19

Transition zone between glandular tissue and squamous epithelium