Carcinoid syndrome

Question 1

Define carcinoid syndrome

Answer 1

Constellation of symptoms caused by systemic release of humoral factors from carcinoid tumours

Question 2

Aetiology of carcinoid syndrome

tumour + 3

Answer 2

Carcinoid tumours = slow going neuroendocrine tumours

Mostly derived from serotonin producing enterochromaffin cells
Produce secretory products like serotonin, histamine, tachykins, kallikrein & prostaglandins
75-80% of patients w/ syndrome have small bowel carcinoids

Question 3

Epidemiology of carcinoid syndrome

3

Answer 3

RARE
Asymptomatic carcinoid tumours more common
10% patients w/ MEN-1 have carcinoid tumours

Question 4

Presenting symptoms of carcinoid syndrome

6

Answer 4

Paroxysmal FLUSHING
Diarrhoea
Crampy abdo pain 
Wheeze
Sweating
Palpitations

Question 5

Signs of carcinoid syndrome on physical examination

5 + 4 crisis

Answer 5

Facial flushing
Telangiectasia
Wheeze
Right sided murmurs (tricuspid stenosis/regurgitation or pulmonary stenosis)
Nodular hepatomegaly (in metastatic disease)

Carcinoid crisis signs
Profound flushing
Bronchospasm
Tachycardia
Fluctuating BP

Question 6

Investigations for carcinoid syndrome

5

Answer 6

24hr urine collection
Bloods
CT or MRI scan
Radioisotope scan
Investigations for MEN-1

Question 7

Investigations for carcinoid syndrome - 24hr urine collection

Answer 7

Check 5-HIAA levels (metabolite of serotonin)

Question 8

Investigations for carcinoid syndrome - bloods

2

Answer 8

Plasma chromogranin A & B

Fasting gut hormones

Question 9

Investigations for carcinoid syndrome - CT or MRI

Answer 9

To localise tumour

Question 10

Investigations for carcinoid syndrome - radioisotope scan

Answer 10

Radio labelled somatostatin analogue helps localise tumour