Gastrointestinal cancers

Question 1

CRC incidence

Answer 1

2nd most common new cancer
3rd most common cancer death

> 50% in >70yrs of age

Curable when localised
5yr survival 63%

Question 2

Staging of CRC

Answer 2

Dukes
1 = Submucosal
2 = through serosa
3 = regional lymph nodes
4 = distant mets

Question 3

Prognostic factors of CRC

Answer 3

DEPTH OF PENETRATION- deeper = poorer
Serosal involvement = poor
LN involvement = poor
Distant mets = poor
Bowel obstruction/perforation 
Extramural LVI

MSI = improved survival

Question 4

Risk factors CRC

Answer 4

Age >50yrs
Family history
Poor intake of fruits and vegetables
EtOH
Obesity
T2DM
IBD

Question 5

Familial CRC?

Answer 5

FAP:

• APC germline mutation
• <1% of CRCs
• CRC by 45yrs

HNPCC:

• Defects in mismatch repair genes - MSH2 and MSH6, MLH1 and MLH3, PMS1 and PMS2
• 2-4% of CRC
• CRC and endometrical cancer

Question 6

Screening for low risk:

- asymptomatic individuals without personal history of IBD or CRC or family history of CRC

Answer 6

98% of population

FOBT every 5yrs from 50yrs

Question 7

Screening for moderately increased risk:

• 1st degree relative <55yrs CRC
• 2 relatives with CRC any age

Answer 7

5yrly Colonoscopy from 50yrs OR 10yrs younger than 1st diagnosis of CRC

Question 8

Screening for high risk:

• > 3 relative with CRC
• > 2 relative and multiple CRCs in 1 person
• CRC <50yrs and endometrial or ovarian cancer
• Suspected FAP in family
• Suspected HNPCC in family

Answer 8

Need genetic counseling ? FAP or HNPCC

FAP:

• Sigmoidoscopy from 12yrs
• Colectomy 25yrswith duodenal screening yrly

HNPCC:
- Colonoscopy yrly from 25yrs

Question 9

Adjuvant chemotherapy

Answer 9

If lymph node disease present = Chemotherapy

5FU or capecitabine +oxaliplatin

Question 10

5FU

Answer 10

5-Fluorouracil

Antimetabolite - pyrimidine analogue
Given with folinic acid

Side effects:

• Lethargy, N+V
• Cardiac toxicity - coronary vasospasm
• Diarrhoea
• Mucositis
• Palmar and plantar erythema

Worse is dihydropyrimidine dehydrogenase deficit

Question 11

Capecitabine

Answer 11

Fluoropyrimidine

Similar side efects to 5FU but more palmar plantar erythema

Question 12

Oxaliplatin

Answer 12

Platinum derivative

Side effects:

• Lethargy
• N+V+D
• Myelosuppression
• Peripheral neuropathy

Question 13

Treatment for metastatic CRC

Answer 13

Chemotherapy - 5FU/capecitabine+oxaliplatin

K-RAS wild type = Bevacizumab and chemotherapy

Fail 1st line and K-RAS wildtype = Cetuximab +/- chemo

Question 14

Liver metastasis in CRC

Answer 14

If liver only mets = resect

Neo-adjuvant chemo may result in resectable margins

Question 15

Rectal cancer treatment

Answer 15

Neoadjuvant chemo and radio

Surgery

Question 16

Gastric cancer risk factors

Answer 16

High intake of salt and salt preserved foods
Low consumption of fruits and vegetables
H. pylori
Smoking
Obesity
GORD

1-3% hereditary diffuse cancers

Question 17

Gastric cancer incidence

Answer 17

Rare <50yrs
2nd leading cause of cancer mortality worldwide

Tend to present late
5yr survival 25%

> 90% are adenocarcinomas

Question 18

Gastric cancer treatment

Answer 18

Radical surgery with adjuvant chemo and radiotherapy

Metastatic disease = chemo
If HER2+ = trastuzumab and chemo