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BRS YR2 > Gastrointestinal Cancers > Flashcards

Gastrointestinal Cancers Flashcards

1
Q

What is the definition of cancer?

A

a disease characterised by the uncontrolled division of abnormal cells in the body

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2
Q

What type of cancer tends to arise from squamous epithelial cells?

A

squamous cell carcinoma

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3
Q

What type of cancer tends to arise from metaplastic columnar epithelial cells?

A

adenocarcinoma

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4
Q

What type of cancer tends to arise from enteroendocrine cells?

A

neuroendocrine tumours (NETs)

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5
Q

What type of cancer tends to arise from interstitial cells of Cajal cells?

A

Gastrointestinal Stromal Tumours (GISTs)

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6
Q

What type of cancer tends to arise from smooth muscle cells?

A

Leiomyoma/leiomyosarcomas

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7
Q

What type of cancer tends to arise from adipose tissue cells?

A

Liposarcomas

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8
Q

What musculature makes up the oesophagus?

A

upper 2/3 = skeletal

lower 1/3 = smooth

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9
Q

Where does the oesophagus start?

A

C5

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10
Q

Where does the oesophagus end?

A

T10

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11
Q

Where do you tend to find squamous cell carcinoma?

A

upper 2/3 of the oesophagus

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12
Q

What pathway is associated with squamous cell carcinoma?

A

acetyldehyde patheay

EtOH to acetate

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13
Q

What is oesophagitis?

A

inflammation of the oesophagus (caused by GORD)

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14
Q

How prevalent is oesophagitis?

A

30% of the UK population

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15
Q

What is Barretts oesophgus?

A

metaplasia of the oesophagus

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16
Q

How prevalent is Barretts oesophgus?

A

5% of the GORD population

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17
Q

What is the risk of cancer with Barret’s oesophagus?

A

0.5-1%/year

30-100 fold risk of cancer

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18
Q

How do oesophageal cancers present?

A
  • late
  • dysphagia
  • weight loss
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19
Q

Where do you tend to find adenocarcinomas in the oesophagus?

A

lower 1/3 of the oesophagus

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20
Q

What tends to cause adenocarcinomas in the oesophagus?

A

acid reflux

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21
Q

What are the Barrett’s surveillance guidelines when no dysplasia is seen?

A

every 2-3 years (endoscopy)

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22
Q

What are the Barrett’s surveillance guidelines when low grade dysplasia is seen?

A

every 6 months

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23
Q

What are the Barrett’s surveillance guidelines when high grade dysplasia is seen?

A

intervention (cancer is highly likely)

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24
Q

What population does squamous adenocarcinoma of the oesophagus most affect?

A
  • elderly patients

- males more than females

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25
Q

How do you diagnose oesophageal cancer?

A

endoscopy and biopsy

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26
Q

How do you stage oesophageal cancer?

A
  • CT scan
  • Laparoscopy
  • ?Endoscopic US
  • ?PET scan
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27
Q

Why to do you do a laparoscopy?

A

to ensure there aren’t any metastases

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28
Q

How do you treat squamous cell cancer?

A
  • radiotherapy
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29
Q

How do you treat adenocarcinomas?

A
  • neo-adjuvant chemotherapy

- followed by surgery

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30
Q

What happens to the palliative instances of oesophageal cancer?

A
  • chemotherapy
  • DXT
  • stent
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31
Q

What happens in a oesophagectomy?

A

Two-stage Ivor Lewis approach

removing parts of the stomach and the oesophagus

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32
Q

What population is most affected by colorectal cancer?

A
  • > 50 years old

- men

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33
Q

What are the different forms of colorectal cancer?

A
  • sporadic
  • familial
  • hereditary syndrome
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34
Q

What is the sporadic form of colorectal cancer?

A
  • Absence of family history
  • Older population
  • Isolated lesion
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35
Q

What is the familial form of colorectal cancer?

A

Family history, higher risk if:

  • index case is young (<50years)
  • the relative is close (1st degree)
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36
Q

What is the hereditary syndrome form of colorectal cancer?

A
  • Family history
  • Younger age of onset
  • Specific gene defects
    e. g.
  • Familial adenomatous polyposis (FAP)
  • Hereditary nonpolyposis colorectal cancer (HNPCC or Lynch syndrome)
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37
Q

How do people with Familial adenomatous polyposis?

A
  • young polyps

- removals of lots of the large colon at a young age

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38
Q

What can cause hyperproliferative epithelium?

A

APC mutation

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39
Q

What can cause a small adenoma?

A

COX-2 overexpression

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40
Q

What can cause a small adenoma to develop into a large adenoma?

A

K-ras mutation

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41
Q

What can cause a large adenoma to develop into a colon carcinoma?

A
  • p53 mutation

- loss of 18q

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42
Q

What is thought to prevent the progression of polyps to colorectal cancers?

A

aspirin

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43
Q

What are the risk factors of developing Colorectal cancers?

A 
PMHx
- colorectal cancers
- adenoma, UC, and radiotherpy
FHx
- first degree relative
- genetic predisposition
Lifestyle
- smoking
- obesity
- socioeconomic status
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44
Q

Where does colorectal cancer occur?

A

2/3 - descending colon, rectum

1/2 - sigmoid colon and rectum (seen on sigmoidoscopy)

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45
Q

How does caecal and right sided cancer present?

A
  • iron deficiency anaemia
  • bowel habit changes (diarrhoea)
  • distal ileum obstruction (late)
  • palpable mass (late)
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46
Q

How does sigmoid and left sided cancer present?

A
  • PR bleeding
  • mucus
  • thin stools (late)
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47
Q

How does rectal cancer present?

A
  • PR bleeding
  • mucus
  • tenesmus
  • anal, perineal and sacral pain
  • bowel obstruction (late)
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48
Q

What are the late signs of local invasion of a carcinoma?

A
  • bladder symptoms

- female genital tract symptoms

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49
Q

What are the late signs of metastasis of a carcinoma?

A
  • liver: hepatic pain, jaundice
  • lung: cough
  • regional lymph nodes
  • peritonism: sister mary joseph nodule
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50
Q

What are the signs of primary colorectal cancer?

A
  • abdominal mass
  • DRE: most <12cm from dentate line and reached by finger
  • rigid sigmoidoscopy
  • abdominal tenderness and distension (large bowel obstruction)
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51
Q

What are the signs of metastasis and complications of colorectal cancer?

A
  • hepatomegaly
  • monophonic wheeze
  • bone pain
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52
Q

How do you diagnose colorectal cancer?

A
  • FIT (faecal immunochemical test) for occult blood
  • FBC: anaemia, haematinitcs, low ferritin
  • tumour markers: CEA (NOT a diagnostic tool)
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53
Q

How do you investigate colorectal cancer?

A
  • colonscopy
  • CT colonoscopy/colonography
  • MRI pelvis
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54
Q

Why is a colonscopy used to investigate colorectal cancer?

A
  • can visualize lesions <5mm
  • small polyps can be removed
  • reduced cancer incidence
  • performed under sedation
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55
Q

Why is a CT colonoscopy/colonography used to investigate colorectal cancer?

A
  • can visualize lesions >5mm
  • no need for sedation
  • less invasive, better tolerated
  • colonoscopy is still needed for diagnosis if lesions are identified
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56
Q

Why is a MRI pelvis used to investigate colorectal cancer?

A
  • depth of invasion
  • mesorectal lymph node involvement
  • no bowel prep or sedation required
  • help choose between preop chemoradiotherapy or straight to surgery
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57
Q

What scans are used to stage a colorectal cancer prior to treatment?

A

CT chest/abdomin/pelvis

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58
Q

How do you manage an obstructing colon carcinoma in the right and transverse colon?

A
  • resection

- primary anastomosis

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59
Q

How do you manage an obstructing colon carcinoma in the left sided colon?

A 
Hartmann's procedure
- proximal end colostomy (LIF)
- reversal in 6 months
Primary anastomosis
- intraoperative bowel lavage with primary anastomosis (10% leak)
- defunctioning ileostomy
Palliative stent
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60
Q

What arteries supply the right and transverse colon?

A
  • Iliocolic
  • Right colic
  • Middle colic
61
Q

What arteries supply the left sided colon?

A
  • Left colic

- sigmoid arteries

62
Q

What happens in a Right Hemicolectomy?

A
  • right side of the large bowel
  • removing the ascending colon, caecum
  • connecting the terminal ileum, to the transverse colon
63
Q

What happens in a Extended Right Hemicolectomy?

A
  • remove 2/3 or the large bowel (caecum, ascending colon and part of the transverse colon)
  • connect terminal ilium to the remainder of the transverse colon
64
Q

What happens in a Left Hemicolectomy?

A
  • remove the descending colon

- connect transverse colon to the sigmoid colon via anastomosis

65
Q

How do you resect with rectal cancer?

A
  • remove the rectum and part of the sigmoid colon

- connect the remaining colon (sigmoid) to the anus

66
Q

What is normally done instead of a resection with rectal cancer?

A

iliostomy

67
Q

What is the most common cause of pancreatic cancer?

A

pancreatic ductal adenocarcimona

68
Q

When does pancreatic cancer tend to present?

A
  • late (80-85%)

only 15-20% have resectable disease

69
Q

When does pancreatic cancer tend to occur?

A

between 60-80 years of age

70
Q

What are the risk factors of pancreatic cancer?

A
  • chronic pancreatitis (18 fold risk)
  • T2DM
  • cholelithiasis
  • previous gastric surgery
  • pernicious anaemia
  • diet (high in fat, protein, coffee and etOH)
  • occupation (chemical and metal exposure)
  • smoking
  • family history (hereditary pancreatitis
71
Q

What are pancreatic intraepithelial neoplasias?

A
  • microscopic (<5mm)

- not visible by pancreatic imaging

72
Q

What happens in the development of pancreatic ductal adenocarcinomas?

A
  • non-invasive neoplastic precursor lesions

- that acquire clonally selected genetic and epigenetic alterations along the way

73
Q

What mutations are associated with PanIN-1?

A

K-Ras mutations

74
Q

What mutations are associated with PanIN-2?

A

CDKN2A

75
Q

What mutations are associated with PanIN-3?

A

BRCA2, TP53

76
Q

How does a carcinoma at the head of the pancreas present?

A

(2/3)

  • Jaundice
  • Weight loss
  • Pain
  • acute pancreatitis
  • GI bleeding
  • vomiting
77
Q

What causes jaundice with a carcinoma at the head of the pancreas?

A
  • invasion or compression of the CBD
  • painless
  • Courvoisier’s sign (palpable gallbladder)
78
Q

What causes weight loss with a carcinoma at the head of the pancreas?

A
  • anorexia
  • malabsorption (due to exocrine insufficiency)
  • diabetes
79
Q

What causes pain with a carcinoma at the head of the pancreas?

A

70%

  • epigastrium
  • radiates to the back (25%)
80
Q

What does pain with a carcinoma at the head of the pancreas indicate?

A
  • posterior capsule invasion

- irresectability

81
Q

What does vomiting with a carcinoma at the head of the pancreas indicate?

A

duodenal obstruction

82
Q

What does GI bleeding with a carcinoma at the head of the pancreas indicate?

A
  • duodenal invasion

- varices (due to portal or splenic wein occlusions)

83
Q

How does a carcinoma at the body and tail of the pancreas present?

A
  • asymptomatic at the early stages
  • weight loss
  • back pain
  • vomiting
  • unresectable at time of diagnosis
  • jaundice unlikely
84
Q

What does vomiting with a carcinoma at the body and tail of the pancreas indicate?

A

(late) - invasion of the DJ flexure

85
Q

What investigations can be done with pancreatic cancer?

A
  • Tumour marker: CA19-9
  • Ultrasonography
  • Dual-phase CT
  • MRI
  • MRCP
  • ERCP
  • EUS
  • laparoscopy and laparascopic US
  • PET
86
Q

What does the Tumour marker: CA19-9 indicate?

A
  • falsely elevated in: pancreatitis, hepatic dysfunction and obstructive jaundice
  • conc. >200U/ml = 90% sensitivity
  • conc. > 1000 = high sensitivity
87
Q

What can an ultrasonography detect?

A
  • identify pancreatic tumours
  • dilated bile ducts
  • liver metastases
88
Q

What can a dual-phase CT detect?

A
  • accurately predict resectability in 80-90% of cases
  • contiguous organ invasion
  • vascular invasion (coeliac axis and SMA)
  • distant metastases
89
Q

What can an MRI detect?

A

detects and predicts resectability with accuracies similar to a CT

90
Q

What can an MRCP detect?

A

provides ductal images without ERCP complications

91
Q

What can an ERCP detect?

A
  • confirms the typical double duct sign
  • aspiration/brushing of the bile-duct system
    0 therapeutic modality - biliary stenting to relieve jaundice
92
Q

What can an EUS detect?

A
  • highly sensitive in the detection of small tumours
  • assesses vascular invasion
  • FNA
93
Q

What can a laparoscopy and laparoscopic US detect?

A

radiologically occult metastatic lesions of liver and peritoneal cavity

94
Q

What can a PET detect?

A

demonstrates occult metastases

95
Q

When do you do a whipple resection?

A

when the carcinoma is at the head of the pancreas

96
Q

What is a whipple resection?

A
  • remove: distal bile duct, gall bladder, distal stomach, all of the duodenum until the jejunum starts
  • bile duct, stomach and remaining pancreas attach to the small intestine
97
Q

What is a TOP resection?

A
  • remove: distal part of pancreas (tail and body), spleen)
98
Q

What are the 4 different types of liver cancer?

A
  • Hepatocellular cancer
  • Cholangiocarcinoma
  • Gall Bladder cancers
  • Colorectal cancer liver metastases
99
Q

Where does hepatocellular cancer occur?

A

in the hepatocytes of the liver itself

100
Q

When does hepatocellular cancer tend to occur?

A
  • when patients have cirrhosis

- HEP B/C and alcohol disease

101
Q

Where does Cholangiocarcinoma occur?

A
  • bile ducts, the bifurcation of the common hepatic duct
102
Q

How do you treat hepatocellular cancer?

A 
(chemo is ineffective)
Optimal is surgical excision with curative intent
- liver transplant
- transarterial haemoembolisation 
- radiofrequency ablation
103
Q

What is associated with gallbladder cancer?

A
  • gallstones
  • porcelain gall bladder
  • chronic typhoid infections
104
Q

How do you treat gallbladder cancer?

A

(chemo is ineffective)

surgical excision with curative intent

105
Q

What is the 5 year survival rate of cancer?

A

stage 2: 64%
stage 3: 44%
stage 4: 8%

106
Q

What does stage 2 gallbladder cancer mean?

A
  • transmural invasion

- excision is effective

107
Q

What does stage 3 gallbladder cancer mean?

A
  • invades the liver

- surgical excision if qualify

108
Q

What does stage 4 gallbladder cancer mean?

A
  • invaded the liver >2cm
  • distal metastases
  • unlikely to qualify for surgery
109
Q

What is thought to cause Cholangiocarcinoma?

A
  • choledochal cyst
  • UC and primary scloerosing cholangitis
  • liver flukes
110
Q

How do you treat Cholangiocarcinoma?

A

surgical excision with curative intent

- in the liver, at the hilum, distally

111
Q

How do you treat secondary liver metastases?

A

(chemo improving)

surgical excision with curative intent

112
Q

How do you surgically resect a hepatocellular cancer?

A

remove the affected part of the liver (as little as possible)

113
Q

How do you surgically resect a gallbladder cancer?

A

remove the gallbladder, all the lymphnodes, liver tissue surrounding

114
Q

How do you surgically resect a Cholangiocarcinoma?

A

remove the half of the liver with the tumour

115
Q

What are the different types of causes of dysphagia?

A
  • abdominal
  • cardiac
  • other
116
Q

What are the structural abdominal causes of upper dysphagia?

A
  • Pharyngeal cancer

- Pharyngeal pouch

117
Q

What are the neurological abdominal causes of upper dysphagia?

A
  • Parkinson’s
  • Stroke
  • Motor neurone disease
118
Q

What are the structural abdominal causes of lower dysphagia?

A 
inside(mural and luminal):
- oesophageal or gastric cancer
- stricture
- Schatzki ring
outside (extrinsic compression):
- lung cancer
119
Q

What are the neurological abdominal causes of lower dysphagia?

A
  • Achalasia

- diffuse oesophageal spasm

120
Q

What are the cardiac causes of lower dysphagia?

A

post-prandial angina

121
Q

What are the other possible causes of lower dysphagia?

A
  • globus sensation

- anxiety

122
Q

How could you differentiate between dysphagia and angina?

A
  • pain seconds after swallowing is unlikely to be angina

- unusual to happen only after meals ?exertional

123
Q

Why can angina occur after meals?

A
  • blood shifts to the bowel for digestion

- blood supply limited through narrowed coronaries

124
Q

How can you differentiate between upper and lower dysphagia?

A

upper: food is painful on swallowing
lower: food is easy to swallow but feels stuck seconds later

125
Q

How can you differentiate between neurological and mechanical cause of dysphagia?

A

if both solids and liquids are difficult to swallow - it is likely neruological

126
Q

What would put a patient at risk of strictures?

A

Hx of reflux

127
Q

What investigations would be done for a suspected oesophageal cancer?

A
  • ECG (rule out cardiac causes)
  • FBC (anaemia)
  • U+Es (dehydration)
  • CXR
  • upper GI endoscopy
128
Q

What is associated with dysphagia?

A

aspiration pneumonia

129
Q

What is needed when considering treatment of lower oesophageal adenocarcinoma?

A
  • Staging CTCAP (look at invasion and metastases)
  • PET scan (anything missed by CT)
  • Staging laparoscopy (last line, very small metastases)f
130
Q

What causes microcytic anaemia?

A
  • Iron deficiency anaemia
  • Anaemia of chronic disease
  • Thalassaemia
  • Sideroblastic anaemia
131
Q

What is classified as microcytic anaemia?

A

MCV<80

132
Q

What causes normocytic anaemia?

A
  • Aplastic anaemia
  • Bleeding
  • Chronic disease
  • Destruction (haemolysis)
  • Endocrine disorders:
    Hypothyroidism
    Hypoadrenalism
133
Q

What is classified as normocytic anaemia?

A

MCV 80-96

134
Q

What causes macrocytic anaemia?

A
  • Foetus (pregnancy)
  • Alcohol excess
  • Thyroid disorders
  • Reticulocytosis
  • B12/Folate deficiency
  • Cirrhosis
135
Q

What is classified as macrocytic anaemia?

A

MCV>96

136
Q

What causes iron deficiency anaemia?

A

blood loss

  • increased demand
  • decreased absorption
137
Q

What are the common gastric causes of iron deficiency anaemia?

A
  • Aspirin/NSAID use
  • Colonic adenocarcinoma
  • Gastric carcinoma
  • Benign gastric ulcer
  • Angiodysplasia
  • Coeliac disease
  • Gastrectomy (decreased absorption)
  • H.pylori
138
Q

What are the common non-GI causes of iron deficiency anaemia?

A
  • Menstruation
  • Blood donation
  • Haematuria (1% of iron deficiency anaemias)
  • Epistaxis
139
Q

Any overt bleeding noticed - to explain iron deficiency anaemia?

A

Blood in stool
Haematuria
Epistaxis
Haemoptysis

140
Q

Generic symptoms of malignancy?

A
  • Weight loss
  • Anorexia
  • Malaise
141
Q

What symptoms that might suggest colorectal cancer?

A
  • Change in bowel habit
  • Blood or mucus in stool
  • Faecal incontinence
  • Tenesmus
142
Q

Symptoms that might suggest an upper GI cancer?

A
  • Dysphagia

- Dyspepsia

143
Q

What does Malena indicate?

A

upper GI bleeding

144
Q

What does bright red PR bleeding indicate?

A
  • lower GI

- haemorrhoids

145
Q

What does blood and stool mixed indicated?

A

large colon issues

146
Q

What tests would you do if colorectal cancer is suspected?

A
  • Urine dipstick (haematuria?)
  • Iron studies (confirm iron deficiency as the cause of microcytic anaemia)
  • anti-TTG (coeliac screening)
  • urgent colonoscopy through the 2-week-wait suspected cancer pathway. - - If negative, an upper GI endoscopy will be organised
147
Q

What qualifies you for the 2-week wait suspected cancer colonoscopy?

A

blood in the stool

148
Q

What tests need to be done to decide on a treatment plan for a descending colon adenocarcinoma?

A
  • Staging CTCAP
    (metastases picked up easily)
  • MRI liver, pelvis
149
Q

How do you manage a descending colon adenocarcinoma T3N0M1?

A
  • resect primary colonic tumour/colonic stent
  • neoadjuvant chemotherapy
  • liver resection

BRS YR2 (70 decks)

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