Colo-rectal cancer

Question 1

What are the risk factors for colorectal cancer?

Answer 1

Familial
Dietary: high intake of animal fat and red meat, low fibre intake, smoking, inactive lifestyle, obesity, alcohol.
Other colorectal conditions: previous colorectal cancer, UC, Crohn’s

Question 2

How long may it take for a polyp to become malignant?

Answer 2

> 10years

Question 3

What are the common presenting symptoms of colorectal cancer?

Answer 3

Change in bowel habit
Abdo pain
Rectal bleeding/mucus
Weight loss and anorexia in advanced tumours
Anaemia (chronic bleeding from tumour site)

Question 4

Everyone between what ages gets screened for colorectal cancer?

Answer 4

60-74 years

Question 5

What diagnostic investigations would you do for suspected colorectal cancer?

Answer 5

Colonoscopy
Flexible sigmoidoscopy
Ba anema
Pre-op assessment includes CT/chest/abdo/pelvus assess metastases

Question 6

What is first line treatment for colorectal cancer?

Answer 6

Surgery

Question 7

What happens in surgery?

Answer 7

Segment of the large bowel resected = hemicolectomy/ sigmoid colectomy/ Hartmann’s procedure

Question 8

What can radiotherapy only be used for?

Answer 8

Rectal cancers

Question 9

Why is radiotherapy used preop?

Answer 9

to reduce the tumour size

Question 10

How often is radiotherapy given pre-op?

Answer 10

Mon-Fri for 5 weeks + chemotherapy

Question 11

Why is radiotherapy given post op?

Answer 11

To reduce incidence of local recurrence or if not all tumour could be removed by surgery

Question 12

What does adjuvant chemotherapy aim to do?

Answer 12

Eradicate micrometastases which have been shed from tumour prior to or during resection

Question 13

What has been the mainstay of adjuvant chemo for 50 years?

Answer 13

Fluorouracil

Question 14

What is the mechanism of action of 5-FU?

Answer 14

converted intracellularly to metabolites that bind to enzyme thymidylate synthetase, inhibiting synthesis of thymidine, DNA and RNA

Question 15

Why is folinic acid given with 5-FU?

Answer 15

to increase the efficacy of 5-FU. it increases and prolongs inhibition of TS which gives improved clinical outcomes.

Question 16

What are the side effects of 5-FU?

Answer 16

Diarrhoea
Stomatitis
Nausea and vomiting
Bone marrow suppression
Hand-foot syndrome
Excessive tear shedding

Question 17

What is Oxaliplatin?

Answer 17

3rd generation platinum derivative

Question 18

What is the mechanism of action of Oxaliplatin?

Answer 18

Cross-links DNA, prevents replication and cell division

Question 19

What are the pros and cons of oxaliplatin?

Answer 19

Less nephrotoxicity than other platinums but 95% suffer neurological side effects

Question 20

What are the side effects of Oxaliplatin?

Answer 20

Peripheral neuropathy
Acute pharyngolaryngeal dysasthesia
Bone marrow suppression
Mild alopecia

Question 21

What is the Oxaliplatinde Gramont regimen (FOLFOX)?

Answer 21

Chemo given every 2 weeks for 12 cycles as outpatient.
Oxaliplatin 85mg/m2 over 2 hours IV infusion
Folinic acid 350mg over 2 hours IV infusion
5-FU 400mg/m2 IV STAT
5-FU 2400mg/m2 IV infusion over 46 hours in portable infusion device
Need Hickan line or PICC

Question 22

What is the drawback of infusional FOLFOX regimen?

Answer 22

increased incidence of hand-foot syndrome with infusional 5-FU

Question 23

What are the issues with infusion devices?

Answer 23

Anxiety for patients
Disposal of cytotoxic waste in patient’s homes
Time-consuming to fill (~30 mins per device)

Question 24

What is the XELOX regimen?

Answer 24

oral oxaliplatin with capecitabine

Question 25

What are the advantages to oral chemotherapy?

Answer 25

Less invasive and distressing for patient No issue with sterility/ short expiry date Reduces pharmacy costs and time Patients can administer medicines to themselves at home

Question 26

What is capecitabine?

Answer 26

A pro-drug of 5-FU

Question 27

How often is Capecitabine given?

Answer 27

Given bd for 14 days out of 21

Question 28

What are the side effects of Capecitabine?

Answer 28

Diarrhoea- treat with loperamide Hand-foot syndrome- treat with moisturisers, dose reduction Nausea and vomiting- treat with antiemetics Stomatitis-treat with mouthwashes e.g. chlorhexidine

Question 29

Is Lonsurf infusional or oral agent?

Answer 29

Oral

Question 30

What is Lonsurf?

Answer 30

Trifluridine-tipiracil

Question 31

How does trifluridine work?

Answer 31

Thymidine analogue. Phosphorylated by thymidine kinase, further metabolised in cells to a DNA substrate and incorporated into DNA, therefore preventing proliferation

Question 32

What is trifluridine rapidly degraded by?

Answer 32

Thymidine phophorylase enzyme

Question 33

What is Lonsurf used for?

Answer 33

Metastatic colorectal cancer

Question 34

How often is Lonsurf taken?

Answer 34

Tablets taken twice daily on days 1-5 and 8-12 of a 28 day cycle until disease progression

Question 35

What are the side effects of Lonsurf?

Answer 35

Diarrhoea/constipation, sore mouth, taste change, bone marrow suppression, anaemia, bleeding, hand-foot syndrome, alopecia, tiredness.

Question 36

What treatment would you give Duke's A cancer?

Answer 36

Surgery only

Question 37

What treatment would you give Duke's B cancer?

Answer 37

Surgery and adjuvant chemo in some cases

Question 38

What treatment would you give Duke's C cancer?

Answer 38

Surgery and adjuvant chemo

Question 39

What treatment would you give Duke's D cancer?

Answer 39

Surgery to relieve obstruction, palliative chemo +/- monoclonal antibodies to relieve symptoms and prolong survival