GI Malignancies and Investigation of the GI Tract Flashcards
1
Q
What are the common GI malignancies?
A
Cancers of the;
- Oesophagus
- Stomach
- Large intestine
- Pancreas
- Liver
2
Q
What is the geographical epidemiology of oesophageal carcinoma?
A
Wide geographical variation, with incidence low in USA, and high around Caspian sea and parts of China
3
Q
What % of malignancies in the UK does oesophageal carcinoma constitute?
A
2%
4
Q
Is oesophageal carcinoma more prevalent in males or females?
A
Males
5
Q
What are the clinical features of oesophageal carcinoma?
A
- Dysphagia
- Weight loss
6
Q
What happens to the clinical features as an oesophageal carcinoma grows?
A
It occludes the lumen and causes the progessive worsening of the dysphagia
7
Q
What investigations are conducted when an oesophageal carcinoma is suspected?
A
- Endoscopy
- Biopsy
- Barium
8
Q
What is the most common type of oesophageal carcinoma?
A
Squamous cell carcinoma
9
Q
Where does squamous cell carcinoma of the oesophagus occur?
A
May occur at any level
10
Q
What is an uncommon type of oesophageal carcinoma?
A
Adenocarcinoma
11
Q
Where does adenocarcinoma of the oesphagus occur?
A
Lower third
12
Q
What is adenocarcinoma of the oesophagus associated with?
A
Barrett’s oesophagus
13
Q
At what stage is oesophageal carcinoma at presentation?
A
Advanced in most cases
14
Q
How does oesophageal carcinoma spread?
A
Direct spread through the oesophageal wall
15
Q
What % of oesophageal carcinomas are resectable?
A
40%
16
Q
What is the prognosis of oesophageal carcinoma?
A
5% five year survival
17
Q
What is the second most common GI malignancy?
A
Gastric cancer
18
Q
How many new cases of gastric cancer are there in England and Wales each year?
A
11,000
19
Q
How common is gastric cancer?
A
Common
20
Q
What % of cancer deaths worldwide are accounted for by gastric cancer?
A
15%
21
Q
Is gastric cancer more common in men or women?
A
Men
22
Q
What is the geographical epidemiology of gastric cancer?
A
Geographical variation, common in Japan, Columbia, and Finland
23
Q
What is gastric cancer associated with?
A
Gastritis
24
Q
What blood group is gastric cancer commoner in?
A
A
25
What is the problem with diagnosing gastric cancer?
Symptoms are often vague
26
What are the clinical features of gastric cancer?
* Epigastric pain
* Vomiting
* Weight loss
27
What investigations are used in the diagnosis of gastric cancer?
* Endoscopy
* Biopsy
* Barium
28
What are the macroscopic features of gastric cancer?
* Fungating
* Ulcerating
* Infiltrative
29
What kind of gastric cancer shows infiltration macroscopically?
Linitis plastica
30
What are the intestinal microscopic features of gastric cancer?
Variable degree of gland formation
31
What are the diffuse microscopic features of gastric cancer?
Single cells and small groups, signet ring cells
32
How far has early gastric cancer spread?
Confined to mucosa and sub-mucosa
33
What is the prognosis of early gastric cancer?
Good
34
How far has advanced gastric cancer spread?
Further spread
35
Where is advanced gastric cancer common?
UK
36
What is the 5 year survival rate for advanced gastric cancer?
~10%
37
How does gastric cancer spread?
* Direct
* Lymph nodes
* Liver
* Trans-coelomic
38
Where does gastric cancer spread directly?
Through the gastric wall into duodenum, transverse colon, and pancreas
39
Where does gastric cancer spread trans-coelomically?
* Peritoneum
* Ovaries
40
Describe the development of advanced gastric cancer from normal gastric mucosa
1. Normal gastric mucosa
2. H. Pylori infection
3. Acute gastritis
4. Chronic active gastritis
5. Atrophic gastritis
6. Intestinal metaplasia
7. Dysplasia
8. Advanced gastric cancer
41
What is cancer generally associated with?
Chronic inflammation
42
Where is gastric cancer common?
Countries with high H. Pylori prevalence
43
Give an example of a country where gastric cancer is common due to high H. Pylori prevalence
Columbia
44
What supports the association between H. Pylori and gastric cancer?
Serological and epidemiological evidence
45
What is the most common GI lymphoma?
Gastric lymphoma
46
What does gastric lymphoma start as?
A low-grade lesion
47
What is gastric lymphoma strongly associated with?
H. Pylori
48
What may eradication of H. Pylori lead to in gastric lymphoma?
Regression of tumour
49
How does the prognosis of gastric lymphoma differ from that of gastric cancer?
It is much better for gastric lymphoma
50
How common are gastrointestinal stromal tumours?
Uncommon
51
What are gastrointestinal stromal tumours derived from?
Interstitial cells of Cajal
52
What is the causative mutation in gastrointestinal stromal tumours?
C-kit (CD117)
53
What is the result of the CD117 mutation in gastrointestinal stomal tumours?
It makes it vulnerable to targeted treatment
54
What behaviour do gastrointestinal stromal tumours display?
Unpredictable;
* Pleomorphism
* Mitoses
* Necrosis
55
What are the types of tumours of the large intestine?
* Adenomas
* Adenocarcinomas
* Polyps
* Anal carcinoma
56
What are the types of large intestine adenomas?
* Dysplasia
* Familial Adenomatous Polyposis (FAP)
* Gardner's Syndrome
57
What is large intestinal dysplasia?
Benign, neoplastic lesions in the large bowel
58
What are the macroscopic features of large intestinal dysplasia?
Sessile or pendunculated
59
What are the microscopic features of large intestinal dysplasia?
Variable degree of dysplasia
60
What is the clinical relevance of large intestinal dysplasia?
Malignant potential
61
What happens to incidence of large intestinal dysplasia in western populations?
It increases with age
62
What kind of syndromes are large intestinal dysplasia?
Genetic
63
What is the inheritance pattern of familial adenomatous polyposis (FAP)?
Autosomal dominant condition
64
Where is the FAP mutation?
Chromosome 5
65
What happens in a patient with FAP by the time they are 20?
There are 1000's of adenomas in the large intestine, giving a high risk of cancer
66
What is Gardner's syndrome?
A similar condition to FAP, with bone and soft tissue tumours
67
What is the most common GI malignancy?
Colorectal cancer
68
How many new cases of colorectal cancer are reported each year in England and Wales?
~25,000
69
What are the macroscopic features of colorectal cancer?
60-70% cases are rectosigmoid fungating/stenotic
70
What are the microscopic changes seen in colorectal cancer?
* Mucinous
* Signet ring cell type
71
How do the microscopic changes differ between different colorectal adenocarcinomas?
They are moderately different
72
How does colorectal cancer spread?
* Direct through bowel wall to adjacent organs *(e.g. bladder)*
* Via lymphatics to mesenteric lymph nodes
* Via portal venous system to liver
73
What staging systems are used for colorectal cancer?
* Dukes
* TMN
74
What are the stages in Duke's staging?
* A - Confined to bowel wall
* B - Through wall, but lymph nodes clear
* C - Lymph node involvement
* C1 - Highest node clear
* C2 - Highest node involved
75
What are the mutations found in colorectal cancer?
* Chromosome 5 *(in FAP related colorectal cancer)*
* Ras mutations
* p53 loss/inactivation
76
At what age does incidence of colorectal cancer peak?
60-70
77
What is the geographical epidemiology of colorectal cancer?
* High in UK and USA
* Low in Japan
78
What conditions increase the incidence of colorectal cancer?
* Polyposis syndromes
* UC and Crohns
79
What is the aetiology of colorectal cancer?
* Low residue diet
* Slow transit time
* High fat intake
* Genetic predisposition
80
What is the outcome of colorectal cancer?
Survival time reduces with increasing Duke's staging
81
Where does colorectal cancer frequently metastasise to in its advanced stages?
Liver
82
Other than adenomas, what are the types of large intestine tumours?
* Carcinoid tumour
* Lymphoma
* Smooth muscle/stromal tumours
83
What kind of tumours are carcinoid tumours of the large intestine?
Neuro-endocrine tumours
84
What kind of behaviour do large intestinal carcinoid tumours display?
Unpredictable
85
How common are large intestinal carcinoid tumours?
Rare
86
Where do lymphomas of the large intestines originate from?
May be primary, or spread from elsewhere
87
How common are lymphomas of the large intestine?
Rare
88
How common are large intestinal smooth muscle/stromal tumours?
Rare
89
What behaviour do large intestinal smooth muscle/stromal tumours display?
Unpredictable
90
What proportion of pancreas carcinomas are found in the head?
2/3
91
What is the morphology of pancreatic carcinomas?
Firm pale mass with a necrotic centre
92
Where may pancreatic carcinomas infiltrate?
Adjacent structures, *e.g. the spleen*
93
What is the most common carcinoma of the pancreas?
Ductal adenocarcinomas
94
What % of pancreatic carcinomas are ductal adenocarcinomas?
80%
95
How do pancreatic carcinomas appear histologically?
Well formed glands
96
What do some pancreatic acinar tumours have histologically?
Zymogen granules
97
What is the prognosis for pancreatic carcinomas?
Poor
98
What hapens in carcinoma of the Ampulla of Vater?
The bile duct is blocked with only a small tumour
99
What does carcinoma of the Ampulla of Vater lead to?
Jaundice
100
What is the prognosis for carcinoma of the Ampulla of Vater?
Good, *because blockage leads to early presentation when the tumour is still treatable*
101
How common are islet cell tumours?
Rare
102
What are the types of islet cell tumours?
* Insulinoma
* Glycagonoma
* Vasoactive Intestinal Peptideoma *(VIPoma)*
* Gastrinoma
103
What does an insulinoma lead to?
Hypoglycaemia
104
What does glycagonoma lead to?
Characteristic skin rash
105
What does vasoactive intestinal peptideoma lead to?
Werner Morrison syndrome
106
What does gastrinoma lead to?
Zollinger-Ellison syndrome
107
Give 3 benign tumours of the liver
* Hepatic adenoma
* Bile duct adenoma/hamartoma
* Haemangioma
108
How common are benign tumours of the liver?
Fairly rare
109
Give 3 malignant tumours of the liver
* Hepatocellular carcinoma
* Cholangiocarcinoma
* Hepatoblastoma
110
How many new cases of colorectal cancer are there in England and Wales per year?
25,000
111
How many new cases of stomach cancer are there in England and Wales per year?
11,000
112
How many new cases of pancreatic cancer are there in England and Wales per year?
5,500
113
What investigations are used to investigate the abdomen?
* Plain x-rays
* Contrast studies
* Ultrasound
* Cross-setional imaging
* Angiography
114
What type of x-rays are used to investigate the abdomen?
* Abdominal x-ray *(AXR)*
* Erect chest x-ray *(CXR)*
115
What kind of contrast studies are used to investigate the abdomen?
* Barium swallow
* Barium enema
* Barium meal/follow through
* Water soluble contrast studies
116
What kind of cross-sectional imaging techniques are used to investigate the abdomen?
* Computed tomography (CT)
* Magnetic resonance imaging (MRI)
117
How big is the dose of radiation given by the techniques used to investigate the abdomen?
Varies considerably
118
Which techniques for investigation of the abdomen don't use any radiation?
* Ultrasound
* MRI
119
Which technique used to investigate the abdomen can deliver a high dose of radiation?
CT scan
120
How does the radiation dosage given during a CT scan differ from that of an abdominal x-ray?
Can be up to 15x the dose
121
What are the potential risks of radiation?
* Carcinogenesis
* Genetic
* Developmental risk to foetus
122
What are contrast studies used to define?
Hollow viscera
123
What contrast is used in studies?
* Barium
* Water soluble contrast *(typically containing iodine)*
124
What are the common types of GI contast studies?
* Swallow
* Meal
* Follow through
* Enema
125
What is a barium enema?
A barium study where the contrast medium is inserted rectally
126
What does a barium enema enable?
The colon to be visualised
127
What does ultrasound utilise to generate images?
Sound waves
128
What frequency sound waves are used in ultrasound?
Usually 2-18MHz
129
What are the advantages of ultrasound?
* Cheap compared to CT and MRI
* Portable
130
What is the disadvantage of ultrasound?
It is highly user dependant
131
What can an abdominal ultrasound be used to do?
* Determine if the patient has gallstones, or if the common bile duct is dilated
* Can view liver and portal vein, even the appendix
132
What is the dilation of the common bile duct an indicator of?
That there is an impacted gallstone in the duct
133
What is the problem with abdominal ultrasounds with the aim to view the liver and portal vein?
The scans are often difficult to interpret, and the usefulness of a scan is often down to who is doing and interpreting the scan
134
What technique is used to visualise the blood supply to the GI tract?
GI angiography
135
When is being able to visualise the blood supply to the GI tract very useful?
For bleeding and ishchaemia
136
How is GI angiography conducted?
By injecting a radio-opaque contrast agent intravenously, and then using various modalities to capture the images
137
What is shown in this GI angiogram?
The aorta, with the coelic trunk, and superior mesenteric arteries and its branches. *The inferior mesenteric artery and it's branches are harder to see*
138
What structures are visable in an abdominal x-ray?
* Stomach
* Small and large bowel
* Soft tissues
* Liver
* Spleen
* Kidneys
* Psoas muscles
* Bladder
* Lung bases
* Bones
139
When is a part of a hollow tube visible on an x-ray?
If it is filled with gas
140
Why are parts of a hollow tube filled with gas visible on an x-ray?
Low density gas acts as contrast
141
When are lumens not visible on abdominal x-rays?
When they are fully fluid filled
142
When is the ability to visualise gas filled areas on an abdominal x-ray useful?
Can be used to visualise the stomach *(if gas filled)*, but more commonly used to visualise the small bowel
143
What are the common reasons for requesting a plain abdominal radiograph?
* Acute abdominal pain
* Small or large bowel obstruction
* Acute exacerbation of IBD
* Renal colic
144
What abnormalities can be shown on an abdominal x-ray?
* Small bowel obstruction
* Large bowel obstruction
* Volvulus
* Chronic pancreatitis
* Aneurysms with calcification
* Nodes
* Bones
* Artifacts
* Foreign bodies
* Kidney stones
145
What position does the small bowel usually occupy on the abdominal x-ray?
Central position
146
What can the small bowel display on an x-ray?
'Circular folds', or valvulae conniventes
147
How do valvulae conniventes appear on x-rays?
As lines that appear to cross the whole of the bowel lumen
148
What is this x-ray image showing?
The large bowel
149
What position does the large bowel usually occupy on an x-ray?
A more peripheral position
150
What is it often possible to see on an x-ray of the larg bowel?
* Haustra
* Faeces
151
How do haustra appear on an abdominal x-ray?
As incomplete lines going across the lumen
152
How do faeces appear on an abdominal x-ray of the large bowel?
Like clouds in the lumen
153
What rule do small and large bowel obstructions follow?
3/6/9
154
What is the 3/6/9 rule?
* A small bowel is said to be dilated when it is greater than 3cm diameter
* The large bowel is said to be dilated when its greater than 6cm diameter
* The caecum *(when the ileoceacal valve is working)* is said to be dialted when it is greater than 9cm diameter
155
What is it important to check when applying the 3/6/9 rule?
That the x-ray is shown to scale
156
What is this image showing?
A small bowel obstruction
157
How does a small bowel obstruction usually present?
* Vomiting *(early)*
* Mild distention
* Absolute constipation *(late feature)*
* Colicky pain that presents every 2-3 minutes
158
What is meant by absoloute constipation?
Not passing anything per rectum, *even flatus*
159
Why do you vomit early, and experience constipation late, with a small bowel obstruction?
Because the obstruction is nearer the mouth than a large bowel obstruction
160
What can cause a small bowel obstruction?
* Adhesions
* Hernias
* Tumours
* Inflammation
161
What kind of hernias can cause a small bowel obstruction?
* Inguinal
* Femoral
* Incisional
162
What is this image showing?
A large bowel obstruction
163
How does a large bowel obstruction appear on an abdominal x-ray?
* More at the periphery of the x-ray
* Lines going across the lumen *(haustra)* are incomplete
164
How does a large bowel obstruction present?
* Abdominal pain
* Distention
* Constipation *(early feature)*
* Colicky pain
* Vomiting *(late feature)*
165
How does the colicky pain present with a large bowel obstruction differ from that with a small bowel obstruction?
It is not as frequent, being experienced every 10-15 minutes
166
What is a feature of vomiting in large bowel obstructions?
Can be faeculant
167
What are the causes of a large bowel obstruction?
* Colorectal carcinoma
* Diverticular stricture
* Hernia
* Volvulus
* Psuedo-obstruction
168
What is a volvulus?
When a viscera twists around itself, or *more commonly* when it twists around its mesentery
169
What is the most common volvulus?
Sigmoid volvulus
170
What is a more rare type of volvulus?
Caecal volvulus
171
What is the consequence of twisting in a volvulus?
The enclosed loop of bowel dilates, and is at risk of perforating or cutting of its blood supply *(which runs in the mesentery)*
172
What is this arrow showing?
Chronic pancreatitis
173
When can an erect chest x-ray be useful?
In diagnosing a perforated bowel
174
What can cause a perforated bowel?
* Peptic ulcer
* Diverticular disease
* Tumour
* Obstruction
* Trauma
* Iatrogenic
175
Why does the CXR need to be erect when trying to diagnose a perforated bowel
Because you are looking for the diaphragm to be elevated away from any other viscera *(the liver on the* by the presence of air/gas in the peritoneal cavity. The air/gas will rise to the top of the cavity and so the patient needs to be sat up for 10 minutes prior to the x-ray to ensure this happens
176
Why is a raised diaphragm indicative of a perforated bowel?
The peritoneal cavity normally only contains a small amount of fluid, so the presence of air/gas is abnormal and could be the result of a perforated bowel
177
What does an x-ray of a raised diaphragm look like?
178
What does an abdominal CT use?
* High dose radiation
* IV or oral/rectal contrast
179
How does the resolution of an abdominal CT differ from that of a MRI?
* Good spatial resolution
* Poor contrast resolution
180
Draw a diagram illustrating the planes of view that can be acheived by an abdominal CT
181
Label this transverse abdominal CT
* A - Liver
* B - Stomach
* C - Oesophagus
* D - Spleen
182
Label this coronal abdominal CT
* A - Right crus
* B - Oesophagus
* C - Stomach *(fundus)*
* Aorta
183
Label this sagittal abdominal CT
* A - Right crus of diaphragm
* B - Celiac artery
* C - Superior mesenteric artery
* D - Oesophagus
* E - Aorta
184
Does MRI imaging use radiation?
No
185
What is the advantage of MRI imaging?
Good spatial and contrast resolution
186
What is the disadvantage of MRI imaging?
Time consuming
187
What is a magnetic resonance cholangio-pancreatogram (MRCP)?
A MRI scan that can visualise the gallbladder and bilary tree
188
Label this diagram
* A - Gall bladder
* B - Stone in gall bladder
* C - Stone in bile duct
* D - Bile duct
