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Flashcards in GI Session 10 Deck (70):
1

What are the clinical features of oesophageal carcinoma?

Progressive worsening dysphasia from dry solids --> liquids and weightloss

2

What are the pathological features of oesophageal carcinoma?

Squamous cell can occur anywhere in the oesophagus
Adenocarcinoma occurs in the lower 1/3 where Barrett's is seen

3

What is the pathogensis of SCC of the oesophagus?

HPV/tannin/vitamin A deficiency/riboflavin deficiency --> dysplasia --> neoplasia

4

What is the pathogensis of adenocarcinoma of the oesophagus?

Metaplaetic epithelium --> dysplasia --> neoplasia

5

What is the prognosis for oesophageal carcinoma?

Most pts present with advanced disease where there is direct spread through the oesophageal wall --> 5% 5-year survival rate

6

Describe the epidemiology of gastric cancer.

Accounts for 15% of cancer deaths worldwide
More common in men
High incidence in Japan, Columbia and Finland
Associated with gastritis and blood group A

7

What are the clinical features of gastric cancer?

Vague symptoms --> epigastric pain, vomiting and weight loss in advanced disease

8

What are the macroscopic pathological features of gastric cancer?

Early is confined to submucosa/mucosa
Late appears fungating, ulcerating, infiltrative

9

What are the microscopic features of gastric cancer?

Intestinal cancers are all adenocarcinomas with variable degrees of gland formation
Diffuse disease --> single cells, small cells, signet ring cells

10

What is the pathogenesis of gastric lymphoma?

H.pylori --> low grade lesion --> neoplasia of B lymphocytes

11

What is the pathogenesis of gastric cancer?

H.pylori --> early confined to mucosa/submucosa --> advanced spreads direct/lymph/liver/trans-coelomic to peritoneum +/- ovaries

12

What is the pathogensis of GI stromal tumours?

Intestinal cells of rajal (gastric pacemaker) become neoplastic --> C-kit serum marker release

13

What is used to assess the risk of unpredictable GI stromal tumours?

Site and size of lesion
Degree of pleomorphism, mitoses and necrosis

14

What is the commonest GI lymphoma?

Gastric

15

What is the prognosis of gastric cancer?

Early gastric = good
Advanced gastric = 10% 5-year survival rate
Lymphoma = good
Stromal = unpredictable

16

How are gastric cancers treated?

Surgery
Chemotherapy
Herceptin
Imatinib for stromal

17

Describe the epidemiology of oesophageal carcinoma.

Accounts for 2% of malignancies in the UK
Higher incidence in men
Highest incidence in China
SCC more common but incidence decreasing, opposite for adenocarcinoma

18

Describe the epidemiology of large intestine adenomas.

Increased incidence with age in western population and increased incidence with genetic syndromes

19

Describe the epidemiology of large intestine adenocarcinomas.

Peak at 60-70 y.o. In UK
Higher incidence in polyposis syndromes, UC and Crohn's

20

Are carcinoid tumour, lymphoma and smooth muscle tumours of the large intestine common?

No, they are rare

21

What are the clinical features of large intestinal adenocarcinomas?

R side rectosigmoid --> anaemia
L side rectosigmoid --> obstructive symptoms

22

What are the pathological features of large intestinal adenomas?

Variable degree of dysplasia microscopically and sessile/pedunculated mascroscopically

23

What are the pathological features of large intestine adenocarcinomas?

60-70% rectosigmoid --> fungating on R, stenotic on L
See microscopically with moderately differentiated adenocarcinoma or occasionally mucinous or signet ring cell type

24

What provides evidence for the adenoma-carcinoma sequence?

Geographical and anatomical distributions very similar
Synchronous lesions
Metachronous lesions
Adenomas with invasion

25

What is the aetiology of large intestine adenomas?

FAP
Gardeners syndrome

26

What is the pathogensis of large intestine adenocarcinoma?

+/- previous Adenoma
Low residue diet/slow transit time/high fat intake/genetics --> neoplasia

27

How does large intestine adenocarcinoma spread?

Directly
Lymph
Portal venous system

28

What is FAP?

Autosomal dominant in chromosome 5 --> 1000s of adenomas by 20 y.o.

29

What is Gardener's syndrome?

Similar to FAP --> nine and soft tissue tumours

30

Where are carcinoid tumours usually found in the large intestine?

Appendix but can be anywhere

31

Why do carcinoid large ins testing tumours have a normal mortality rate despite being hard to predict?

Rarely metastasise

32

How is the prognosis of large insets tonal adenocarcinoma assessed?

Duke's staging then TNM

33

What is commonly seen in advanced large intestine adenocarcinoma?

Liver metastases

34

What are the Tx options for adenocarcinoma of the large intestine?

Palliative chemotherapy
Resection of liver deposits
Local radiotherapy for rectal cancer

35

What are the primary malignant tumours of the liver?

Hepatocellular carcinoma
Cholangiocarcinoma
Helatiblastoma

36

What are the clinical features of carcinoma of the pancreas?

Early symptoms vague --> diagnosis delayed until weight loss, jaundice or Trossaeu's sign seen

37

What is Trosseau's sign?

Trypsin release --> fleeting thrombophlebitis

38

What can imagine allow in carcinoma of the pancreas?

Radiological diagnosis from small lesions

39

What are the pathological features of carcinoma of the pancreas?

2/3 in head --> firm pale mass which on cutting appears necrotic/haemorrhagic/cystic
80% ductal with well formed glands +/- mucin
Some acinar tumours contain zymogen granules

40

What is the aetiology of carcinoma of the pancreas?

Islet cell tumours (rare)
Gastrinoma --> Z-E syndrome
Insulinoma --> hypoglycaemia
Glucagonoma --> definitive skin rash
(Vasoactive intestinal peptide) VIPoma -->Werner Morrison syndrome

41

What is the prognosis for any type of carcinoma of the pancreas?

Poor

42

What methods can be used to image the GI tract?

Plain X-rays
Contrast studies: barium swallow/enema/meal/follow through or water-soluble contrasts
US
CT for emergency pts
MRI
Angiography

43

When should an AXR be requested?

Small/large bowel obstruction
Acute IBD exacerbation
?toxic megacolon

44

When should an AXR not be requested?

Acute abdominal pain (most causes not visible)
Renal colic
Constipation

45

What projection are all AXR?

AP

46

What should be included in an AXR?

Public tubercle
T5
Properitoneal fat stripes

47

When might properitoneal fat stripes not be visible?

Lost on pathology e.g. appendicitis

48

What contents should be seen in the bowel due to its transit time?

Stomach (medium t.t.) = fluid and lots of gas
Small bowel (fast t.t.) = fluid
Large bowel (slow t.t.) = faeces +/- gas

49

How can the small bowel and colon be distinguished on AXR?

Small bowel is central with valvulae conniventes
Colon is peripheral with haustra

50

How is the rule of 3s used to assess abnormal gas patterns?

>3 cm = small bowel obstruction
>6 cm = large bowel obstruction with incompetent iliocaecal valve
>9cm = large bowel with competent iliocaecal valve

51

What soft tissues should be identifiable on a normal AXR?

Liver
Spleen
L+R kidneys
Bladder
Psoas muscle

52

What can be used as an approximate measure of 3 cm on radiograph?

Vertebral body height

53

What causes small bowel obstructions?

Adhesions from surgery
Hernias esp inguinal
Tumours
Inflammation

54

What are the progressive S/S of small bowel obstruction?

Vomiting --> mild distension --> absolute constipation --> colicky pain

55

What causes large bowel obstruction?

Colorectal carcinoma
Diverticular stricture
Hernia
Volvulus
Pseudo-obstruction

56

What are the S/S of large bowel obstruction?

Vomiting (faeculant when late)
Significant distension
Pain
Early absolute constipation

57

What is the pathogenesis of volvulus?

Twisting around mesentery--> enclosed bowel loop --> dilation --> perforation and ischaemia

58

Why causes volvulus in the caecum?

Lack of mesentery

59

How does sigmoid volvulus appear on AXR?

Starts in LIF --> coffee bean sign to RUQ --> proximal bowel obstruction

60

What is the pathogenesis of toxic megacolon?

Acute deterioration of UC --> colonic dilatation --> oedema and pseudopolyps

61

What is the pathogenesis of lead pipe colon?

UC causes chronic inflammation --> loss of haustra so featureless colon

62

What is thumbprinting on AXR?

Active inflammation often in UC but also oedematous processes --> oedematous thickened haustra --> thickened wall

63

What extra-GI abnormalities are visible on AXR?

Renal calculi
Chronic pancreatitis
Vascular calcification
AAA
Foreign bodies

64

What is the pathogensis of pneumoperitoneum?

Peptic ulcer/diverticular/tumour/obstruction/trauma/iatrogenic --> air under diaphragm

65

What is used to identify pneumoperitoneum?

Erect CXR after sitting for 10-20 mins
CT

66

What is visible on CT taken at T12?

Loves of liver
Curves of stomach
Coeliac trunk
AA
IVC
Hepatic veins

67

What is seen on CT taken at L1?

(Transpyloric plane of Addison)
Lobes of liver
Pancreatic head
Renal hila
Spleen
Transverse colon

68

What are the advantages of using CT to image the abdomen?

Gives good spatial resolution
Reformatting can be used to identify mechanisms of injury
Can be used to build virtual colonoscopy instead of barium enema

69

What are the applications of MRI in imagine the abdomen?

Good spatial and contrast resolution
Moving object cause blurring but this can be used with fluid to examine peristalsis in Crohn's (absent in active disease)

70

What is the clinical application of abdominal US?

Cheap and portable but highly user dependent
Gallstones
Dilated CBD
Examine bowel wall layers e.g. In appendix
Combine with endoscopy