Colorectal tumours

Question 1

How prevalent is colorectal cancer?

Answer 1

3rd most common cancer worldwide

Question 2

Fill in the gap: colorectal cancer is the __ most common cause of cancer death in the UK

Answer 2

2nd

Question 3

What type of cancers are most colorectal tumours?

Answer 3

adenocarcinomas

Question 4

What is the most common cause of adenocarcinoma transitions in the bowel?

Answer 4

chromosomal instability (CIN)

Question 5

What is chromosomal instability?

Answer 5

The sequential accumulation of genetic mutations of tumour suppressor genes and oncogenes

Question 6

Name 2 tumour suppressor genes associated with colorectal cancer:

Answer 6

1) APC
2) TP53

Question 7

Name 2 oncogenes associated with colorectal cancer:

Answer 7

1. BRAF
2. KRAS

Question 8

The mutation of which gene often triggers the cancerous pathway in the bowel?

Answer 8

APC (adenomatous polyposis coli)

Question 9

Give 8 risk factors for colorectal cancer:

Answer 9

1. Family history
2. IBD
3. Smoking and alcohol
4. Hereditary non-polyposis colorectal cancer
5. Familial adenomatous polyposis
6. diet
7. Increase age
8. Obesity

Question 10

Describe a high risk diet for colorectal cancer:

Answer 10

high in red and processed meat and low in fibre

Question 11

Is familial adenomatous (FAP) autosomal dominant or recessive?

Answer 11

dominant

Question 12

what gene is mutated in FAP?

Answer 12

APC

Question 13

Describe familial adenomatous polyposis:

Answer 13

a defect in the APC gene causing many polyps to form in the large intestine - these polyps have the potential to become cancerous

Question 14

What prophylactic treatment is offered to patients diagnosed with FAP?

Answer 14

they have a full colectomy to prevent development of bowel cancer

Question 15

What is another name given to hereditary non-polyposis colorectal cancer (HNPCC)

Answer 15

Lynch Syndrome

Question 16

Is HNPCC autosomal dominant or recessive?

Answer 16

Dominant

Question 17

Describe HNPCC:

Answer 17

a hereditary condition that results in mutations of DNA mismatch repair genes that puts patients at a high risk for a number of cancers, particularly colorectal cancers

Question 18

What % of colorectal cancers are caused by FAP?

Answer 18

less than 1%

Question 19

What % of colorectal cancers are caused by HNPCC?

Answer 19

2-3%

Question 20

Where are most colorectal cancers found in the large intestine?

Answer 20

sigmoid colon and rectum

Question 21

Give 7 clinical features associated with colorectal cancer:

Answer 21

1) persistant and unexplained change in bowel habit
2) rectal bleeding
3) abdominal pain
4) abdominal bloating
5) unexplained weight loss
6) fatigue
7) iron deficiency anaemia

Question 22

True or false: unexplained iron deficiency anaemia warrants a two week wait referral for urgent cancer testing

Answer 22

True

Question 23

What referral process is used for red flags of colorectal cancer?

Answer 23

two week wait urgent cancer referral

Question 24

When would a colorectal cancer patient present acutely to hospital?

Answer 24

obstruction (tumour blocks the passage through the bowel - surgical emergency)

Question 25

Give 3 acute symptoms associated with a colorectal cancer obstruction:

Answer 25

1) vomiting
2) abdominal pain
3) absolute constipation

Question 26

What is the GP test and screening program tool for bowel cancer?

Answer 26

FIT testing (faecal immunochemical tests)

Question 27

What group of people are included in the England bowel cancer screening program?

Answer 27

people aged 60-74 are sent a home FIT test every 2 years

Question 28

What is the gold standard investigation for colorectal cancers?

Answer 28

colonoscopy with biopsy of suspicious lesions

Question 29

What is the name given to endoscopy of the rectum and sigmoid colon only?

Answer 29

sigmoidoscopy

Question 30

What imaging technique may be considered for patients less fit for a colonoscopy?

Answer 30

CT colonagraphy

Question 31

What imaging technique is often used to visualise metastases for staging?

Answer 31

CT TAP (thorax, abdomen, pelvis)

Question 32

What tumour marker is sued to predict relapse in patients previously treated for colorectal cancer?

Answer 32

carcinoembryonic antigen (CEA)

Question 33

Give an overview of the TNM staging system used in colorectal cancer:

Answer 33

1) tumour - the degree of intestinal wall invasion
2) nodes - lymph node involvement
3) the presence of distant metastases

Question 34

Give the four main treatment options for colorectal cancer:

Answer 34

1) surgical resection
2) chemotherapy
3) radiotherapy
4) palliative care

Question 35

What type of surgery is used to resect colorectal cancers?

Answer 35

laparoscopic surgery

Question 36

Describe the steps in colorectal cancer resection: (4)

Answer 36

1) the tumour is identified
2) the section of bowel containing the tumour is removed
3) the remaining ends are sewed back together (anastomosis)
4) OR a stoma is created by bringing an open section of the bowel onto the skin

Question 37

Give 4 potential complications of bowel cancer surgery:

Answer 37

) damage to nerves, bladder, ureter or bowel
2) DVT and PE
3) infection
4) incisional hernias

Question 38

What is low anterior resection syndrome:

Answer 38

a condition that may occur after resection of a portion of the bowel from the rectum with anastomosis between the colon and rectum

Question 39

Give 3 presentations associated with low anterior resection syndrome:

Answer 39

1) urgency and frequency of bowel movements
2) faecal incontinence
3) difficulty controlling flatulence

Question 40

Give 4 complications associated with colorectal cancer:

Answer 40

1) metastasis
2) bowel obstruction
3) bowel perforation
4) fistulas

Question 41

What is the most common site of metastasis for cancer in the large intestine?

Answer 41

liver

Question 42

What is the most common site of metastasis for rectal cancer?

Answer 42

thoracic organs and nervous system