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AIP: Diarrhoea > Colorectal cancer > Flashcards

Colorectal cancer Flashcards

1
Q

Where is colorectal on the ranking for commonest cancers in UK, and cause of cancer deaths?

A

Third most common type in UK, second most cause of cancer deaths

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2
Q

What are the 5 locations of colorectal cancer and relative averages?

A
  1. Rectal: 40%
  2. Sigmoid: 30%
  3. Ascending colon and caecum: 15%
  4. Transverse colon: 10%
  5. Descending colon: 5%
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3
Q

What are the 3 types of colon cancer?

A
  1. Sporadic (95%)
  2. Hereditary non-polyposis colorectal carcinoma (HNPCC 5%)
  3. Familial adenomatous polyposis (FAP <1%)
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4
Q

What have studies shown that sporadic colon cancer may be due to?

A

A series of genetic mutations, e.g.:

  • >50% show allelic loss of APC gene
  • other series of abnormalities: activation of K-rase oncogene, deletion of p53 and DCC tumour suppressor genes → can lead to invasive carcinoma
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5
Q

What is the inheritance pattern of HNPCC (hereditary non-polyposis colorectal carcinoma)?

A

Autosomal dominant

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6
Q

What is the most common form of inherited colon cancer?

A

HNPCC (hereditary non-polyposis colorectal carcinoma)

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7
Q

What proportion of patients with the gene for HNPCC develop cancer?

A

Around 90%

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8
Q

What are 3 features of colorectal cancer caused by HNPCC?

A
  1. Often in proximal colon
  2. Poorly differentiated
  3. Highly aggressive
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9
Q

How many mutations have been identified that lead to HNPCC (hereditary non-polyposis colorectal carcinoma) and what effects do they have?

A

7; affect genes involved in DNA mismatch repair leading to microsatellite instability

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10
Q

What are the 2 most common genes involved in HNPCC (hereditary non-polyposis colorectal carcinoma)?

A
  1. MSH2 (60%)
  2. MLH (30%)
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11
Q

What type of cancer are patients with HNPCC also commonly at risk of, alongisde a higher risk of other cancers?

A

Endometrial cancer

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12
Q

What criteria are sometimes used to aid diagnosis of colorectal cancer in HNPCC, and what 3 things does this consist of?

A
  • The Amsterdam criteria
  1. at least 3 family members with colon cancer
  2. the cases span at least 2 generations
  3. at least one case diagnosed before the age of 50 years
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13
Q

What is the inheritance pattern of FAP (familial adenomatous polyposis)?

A

Autosomal dominant

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14
Q

What does the condition FAP (familial adenomatous polyposis) result in?

A

Formation of hundreds of polyps by the age of 30-40 years; patients inevitably develop carcinoma

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15
Q

What is the genetic cause of FAP (familial adenomatous polyposis)?

A
  • Mutation in a tumour suppressor gene called adenomatous polyposis coli gene (APC), located on chromosome 5
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16
Q

What investigation can be performed in suspected FAP (familial adenomatous polyposis)?

A

Genetic testing: analysing DNA from a patient’s white blood cells

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17
Q

What is the usual treatment of FAP (familial adenomatous polyposis)?

A

Patients generally have a total colectomy with ileo-anal pouch formation in their twenties

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18
Q

What type of tumours are patients with FAP also at risk of (in addition to colorectal carcinomas)?

A

Duodenal tumours

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19
Q

What is Gardner’s syndrome and what are 4 features?

A
  • Variant of FAP
  1. Features osteomas of the skull and mandible
  2. Retinal pigmentation
  3. Thyroid carcinoma
  4. Epidermoid cysts on the skin
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20
Q

What is the lifetime risk of colorectal cancer in the UK population?

A

5% (1 in 20?! that’s actually quite high)

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21
Q

What are 2 key features of FAP (familial adenomatous polyposis)?

A
  1. More than 100 adenomatous polyps affecting the colon and rectum
  2. Duodenal and fundic glandular polyps (polyps in upper portion of stomach)
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22
Q

In addition to FAP and HNPCC, what are 4 other inherited colorectal cancer syndromes?

A
  1. Turcot’s syndrome
  2. Peutz-Jeghers syndrome
  3. Cowden disease
  4. MYH associated polyposis
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23
Q

What are 3 features of Turcot’s syndrome?

A
  1. Polyposis
  2. Colonic tumours
  3. CNS tumours
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24
Q

What are 2 types of mutations that can cause Turcots syndrome?

A
  1. APC + MLH1
  2. PMS2
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25
Q

What are 2 features of Peutz-Jeghers syndrome?

A
  1. Hamartomatous polyps (overgrowth of multiple aberrant cells, mostly benign, due to systemic genetic condition) in GI tract
  2. Increased risk of GI malignancy
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26
Q

What are 2 possible genes involved in Peutz-Jegher’s syndrome?

A
  1. LKB1
  2. STK11
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27
Q

What are 5 features of Cowden disease?

A
  1. Multiple hamartomas (also known as multiple hamartoma syndrome):
  2. Multiple mucocutaneous lesions
  3. Trichilemmomas (benign follicular neoplasms)
  4. Oral papillomas
  5. Acral keratosis (warty papules on upper surface of hands and feet)
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28
Q

What are 4 diseases that the multiple hamartomas of Cowden’s disease can lead to?

A
  1. Breast carcinoma - 50%
  2. Fibrocystic disease of breast - 75% of women
  3. Thyroid disease (may include malignancy) - 75%
  4. Bowel involvement in 85%
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29
Q

What is the gene that is involved in 85% of cases of Cowden disease?

A

PTEN

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30
Q

What is the gene involved in MYH associated polyposis?

A

MYH

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31
Q

What is the lifetime incidence of colorectal cancer in untreated FAP?

A

100%

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32
Q

What proportion of cases of FAP are caused by de novo germ line mutations showing no prior family history?

A

up to 25%

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33
Q

What proportion of sporadic colorectal cancers have somatic mutations that inactivate the gene APC?

A

up to 80%

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34
Q

What is the role of the APC protein, coded for by the APC gene that is affected in most cases of FAP and also non-inherited colorectal cancer?

A

Likely multiple critical cellular functions, best established role is as a major binding partner and regulator of the ß-catenin protein, in the so-called canonical or ß-catenin dependent Wnt signaling pathway

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35
Q

What gene is often involved in non-inherited colorectal cancer and in what way?

A

APC: somatic mutations that inactivate APC, both alleles usually affected

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36
Q

What is another name for HNPCC (hereditary non-polyposis colorectal carcinoma)?

A

Lynch syndrome

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37
Q

On which side are tumours more likely to be in HNPCC?

A

Right sided

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38
Q

What histology are tumours in HNPCC more likely to show?

A

More likely to be mucinous and have dense lymphocytic infiltrates

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39
Q

What should be excluded and how should verification be made of a diagnosis of HNPCC?

A

Exclude FAP

Verify tumour by pathological identification

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40
Q

What proportion of individuals who fulfill the Amsterdam criteria will not be found to have evidence of mismatch repair gene defects on genetic testing?

A

60% (still increased risk of colorectal cancer, but not as much as if they had the mismatch repair gene defects)

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41
Q

What are KRAS genes?

A
  • RAS family of small G proteins which act as molecular switches downstream of growth factor receptors
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42
Q

In what proportion of colorectal cancers are KRAS or the other 2 in the family (NRAS and HRAS) the site of mutation?

A

40%

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43
Q

Which type of colorectal adnomas tend to have KRAS mutations when examined?

A

Larger tumours, >1cm

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44
Q

What is the usual function of the p53 gene?

A

Functions as a key transcriptional regulator of genes that encode proteins with functions in c_ell-cycle checkpoints_ at the G1/S and G2/M boundaries, in promoting apoptosis, and in restricting angiogenesis

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45
Q

Why do gene mutations in p53 cause colorectal cancer?

A
  • Normally, stresses on tumour cells activate cell-cycle arrest, apoptosis, and anti-angiogenic pathways
  • Many colonic tumours will demonstrate changes in the p53 gene that may facilitate tumour progression through from adenoma to carcionma
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46
Q

What is the inheritance pattern of Cowden syndrome?

A

Autosomal dominant (rare)

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47
Q

In which decade of life is Cowden syndrome most commonly diagnosed?

A

Third decade of life (i.e. twenties)

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48
Q

What is the risk of developing colorectal cancer in Cowden syndrome?

A

15-20%

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49
Q

What screening recommended in Cowden syndrome and why?

A

Regular colonoscopic screening from age 45 due to colorectal cancer risk

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50
Q

What is meant by an oncogene?

A

Gene which has the potential to induce cellular proliferation and avoid apoptosis

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51
Q

What is usually the effect of oncogene mutations and how do they appear in tumours?

A

Usually gain of function, therefore dominant

Increased expression of oncogenes found in most tumours

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52
Q

What is a tumour suppressor gene?

A

Genes that inhibit cellular proliferation or induce apoptosis

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53
Q

What is the effect of a mutation in a tumour suppressor gene?

A

Loss of function mutations, therefore recessive

Mutations in both tumour suppressor gene alleles allow cells to proliferate without restraint

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54
Q

What do most colorectal cancers develop from?

A

Adenomatous polyps

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55
Q

What percentage has screening for colorectal cancer been shown to reduce mortality by?

A

16%

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56
Q

What are the 2 types of screening for colorectal cancer offered by the NHS?

A
  1. Home based, faecal immunochemical test (FIT) screening to older adults
  2. One-off flexible sigmoidoscopy being rolled out
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57
Q

Which people are screened using faecal immunochemical test (FIT) screening, and how frequently?

A

Everyone aged 60-74 years in England, 50-74 years in Scotland, every 2 years. Patients over 74 years may request screening

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58
Q

What does the faecal immunochemical test (FIT) involve?

A

Sent test through post, uses antibodies that specifically recognise human haemoglobin

Used to detect and can quantify the amount of human blood in a single stool sample

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59
Q

What are 2 advantages of FIT over the conventional FOB test?

A
  1. Only detects human haemoglobin as opposed to animal haemoglobin ingested through diet
  2. Only one faecal sample needed compared to 2-3 for FOB
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60
Q

What info do the patient/ GP receive about the result of the FIT test to screen for colorectal cancer?

A

Numerical value is generated but not reported to them; just told if test is normal or abnormal

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61
Q

What is the next step if the result of a FIT (faecal immunochemical test) is positive?

A

Offered colonoscopy

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62
Q

At colonoscopy following abnormal FIT (faecal immunochemical test), what proportion will

  1. have a normal exam
  2. have polyps
  3. have cancer?
A
  1. 5 in 10
  2. 4 in 10
  3. 1 in 10
63
Q

What may be the next step if a patient has a positive FIT, then has polyps on colonoscopy which follows?

A

May be removed due to their premalignant potential

64
Q

What is the aim of flexible sigmoidoscopy screening for bowel cancer?

A

Aim is to detect asymptomatic cancers, but also allow detection and treatment of polyps, reducing the future risk of colorectal cancer

65
Q

How do patient info leaflets refer to flexible sigmoidoscopy screening for colorectal cancer?

A

Bowel scope screening

66
Q

At what age is flexible sigmoidoscopy screening for colorectal cancer offered?

A

One-off screening at 55 years old; patients can self refer up to the age of 60 if didn’t take up offer at age 55

67
Q

What are 4 situations when you should use a 2 week wait referral to colorectal services i.e. cancer pathway?

A
  1. Patient 40 or older with unexplained weight loss AND abdominal pain
  2. Patient 50 or older with unexplained rectal bleeding
  3. Patient 60 or older with iron deficiency anaemia or change in bowel habit
  4. test with occult blood in their faeces
68
Q

What are 3 situations when a 2 week wait referral for colorectal cancer should be considered?

A
  1. Rectal or abdominal mass
  2. Unexplained anal mass or anal ulceration
  3. Patients <50y with rectal bleeding AND any of the following:
  • abdo pain
  • change in bowel habit
  • weight loss
  • iron deficiency anaemia
69
Q

What are 3 additional scenarios when FOBT (faecal occult blood testing - or would they use FIT instead now) should be used, in addition to the usual screening regime?

A
  1. Patients > 50y with unexplained abdominal pain OR weight loss
  2. Patients <60 years with changes in bowel habit OR iron deficiency anaemia
  3. Patients >60y who have anaemia even in the absence of iron deficiency
70
Q

What does Dukes’ classification describe?

A

The extent of spread of colorectal cancer

71
Q

What is each of the 4 Dukes’ stages, and the description and 5 year survival for each?

A
  • DUKES’ A: tumour confined to the mucosa, 95%
  • DUKES’ B: tumour invading bowel wall, 80%
  • DUKES’ C: lymph node metastases, 65%
  • DUKES’ D: distant metastases, 5% (20% if resectable)
72
Q

What are 3 investigations which should/ may be performed as part of colorectal cancer staging?

A
  1. CT of the chest/ abdomen and pelvis
  2. Entire colon evaluated with colonoscopy OR CT colonography
  3. If tumour lies below peritoneal reflection: mesorectum evaluated with MRI
73
Q

What is nearly always the treatment of colorectal cancer, and what are 3 things which may be used as palliative adjuncts?

A

Surgery - resectional surgery is only option for cure (tailored to patient and location)

  1. Stents
  2. Surgical bypass
  3. Diversion stomas
74
Q

What are most resections of colon cancer tailored around and why?

A

Most tailored around resection of particular lymphatic chains e.g. ileo-colic pedicle for right sided tumours, as lymphatic drainage of the colon followings the arterial supply

75
Q

What is an example of a confounding factor that could govern the choice of surgical procedures to treat colon cancer?

A

Tumour in a patient from a HNPCC family may be better served with a panproctocolectomy rather than segmental resection

76
Q

What are 3 technical factors for an anastomosis to heal which is formed following resection of the colon?

A

3 technical factors for healing:

  1. adequate blood supply
  2. mucosal apposition
  3. no tissue tension
77
Q

What are 3 things that could compromise the technical factors needed for an anastomosis to heal following bowel resection and what should be done in the instance of these occurring?

A
  1. Surrounding sepsis
  2. Unstable patients
  3. Inexperienced surgeons

May be safer to construct end stoma rather than attempting anastomosis

78
Q

What are the 2 options when a colonic cancer presents with an obstructing lesion?

A
  1. stent it
  2. resect
79
Q

In modern practice, how does management of obstructive colonic vs rectal tumours differ?

A

Unusual to defunction a colonic tumour with a proximal loop stoma, but in the rectum you need to be staged properly first, so should have a defunctioning loop colostomy before resection can occur

80
Q

What is offered to patients with risk factors for disease recurrence (for colorectal cancer) following resection?

A

Chemotherapy, commonly a combo of 5FU and oxaliplatin

81
Q

What are the 2 types of resection that can be performed on rectal tumours and what is the key thing that governs the choice of which?

A
  1. Anterior resection
  2. Abdomino-perineal excision of rectum (APER)

Involvement of the sphincter complex or very low tumours require APER (also need 2cm resection margin, could influence decision)

82
Q

What is the clearance margin required for resection of tumours in the rectum?

A

2cm - could impact type of procedure chosen

83
Q

For rectal tumours, what is an integral part of the procedure in addition to excision of the rectal tube?

A

Meticulous dissection of the mesorectal fat and lymph nodes (total mesorectal excision / TME)

84
Q

What is there a high risk of with the circumferential resection margin for rectal cancer?

A

High risk of disease recurrence

85
Q

What is a form of treatment which can be offered for rectal, but not colonic, cancers?

A

Irradiation, because the rectum is an extraperitoneal structure

86
Q

What is offered to some patients for rectal cancer prior to resectional surgery and why?

A

Offered long and short course neoadjuvant radiotherapy, because it is an extraperitoneal structure so can receive irradiation (unlike colon)

87
Q

Which patients with rectal cancer are not offered irradiation prior to resectional surgery?

A

Patients with T1 and 2/N0 disease on imaging, should proceed straight to surgery

88
Q

In addition to resection, what treatment is offered to patients with T4 rectal cancer?

A

long course chemo-radiotherapy

89
Q

What are patients with T3, N0 rectal cancer offered prior to resectional surgery?

A

Short course radiotherapy

90
Q

Why shouldn’t patients presenting wiht large bowel obstruction from rectal cancer undergo resectional surgery without staging? 3 reasons

A
  1. Rectal surgery is more techincally demanding than colon cancer
  2. Anastomotic rate is higher
  3. Danger of a positive resection margin in an unstaged patient is high
91
Q

When should patients with rectal cancer not undergo resectional surgery without staging?

A

When patients present with large bowel obstruction from the rectal cancer

92
Q

What treatment should patients with obstructing rectal cancer undergo?

A

Should have a defunctioning loop colostomy, then be staged, before resectional surgery takes place (due to importance of staging before resection - colostomy in meantime)

93
Q

What type of resection AND anastomosis is used for distal transverse colon tumours?

A

left hemicolectomy; colo-colic anastomosis

94
Q

What type of resection AND anastomosis is used for proximal transverse colon tumours?

A

Right hemicolectomy; ileo-colic anastomosis

95
Q

What type of resection AND anastomosis is used for ascending colon tumours?

A

Right hemicolectomy; ileo-colic anastomosis

96
Q

What type of resection AND anastomosis is used for descending colon tumours?

A

Left hemicolectomy; colo-colic anastomosis

97
Q

What type of resection AND anastomosis is used for caecal tumours?

A

Right hemicolectomy; ileo-colic anastomosis

98
Q

What type of resection AND anastomosis is used for sigmoid colon tumours?

A

High anterior resection; colo-rectal anastomosis

99
Q

What type of resection AND anastomosis is used for upper rectum tumours?

A

Anterior resection (TME: total mesorectal excision); colo-rectal anastomosis

100
Q

What type of resection AND anastomosis is used for low rectum tumours?

A

Anterior resection (low TME); colo-rectal anastomosis ± defunctioning stoma

101
Q

What type of resection and anastomosis is used for anal verge tumours?

A

Abdomino-perineal excision of rectum; no anastomosis

102
Q

In what situation is the risk of an anastomosis much greater, and particularly with which type of anastomosis?

A

In the emergency setting where the bowel has perforated, particularly when anastomosis is colon-colon

103
Q

What should be done instead of an anastomosis in the emergency setting where the bowel has perforated?

A

End colostomy is often safer, and can be reversed later

104
Q

What is Hartman’s procedure?

A

When resection of the sigmoid colon is performed and an end-colostomy is fashioned

105
Q

What is a safe type of anastomosis following left-sided bowel resection, even in the emergency setting?

A

Ileo-colic anastomoses are relatively safe (unlike colo-colic) even in the emergency setting, do not need to be defunctioned

106
Q

What are 7 key symptoms of colorectal cancer?

A
  1. PR bleeding: mixed with stool
  2. Change in bowel habits >4 weeks (looser, alternate btw diarrhoea and constipation)
  3. Tenesmus
  4. Palpable mass - rectal or abdo, pain
  5. Anaemia (microcytic) - tumours bleed slowly over time
  6. Weight loss
  7. Bowel obstruction: abdo pain, constipation, vomiting
107
Q

What are 5 differential diagnoses for colorectal cancer?

A
  1. Haemorrhoids
  2. Diverticular disease
  3. Angiodysplasia in colon
  4. Infections
  5. Inflammatory bowel disease
108
Q

What are 4 of the most common symptoms for right sided colorectal cancer?

A
  1. Anaemia e.g. fatigue
  2. Pain
  3. Mass
  4. Mild diarrhoea
109
Q

What are 3 of the most common symptoms for left sided colorectal cancer?

A
  1. Pain
  2. Bleeding and mucus per rectum
  3. Change in bowel habit
110
Q

What are 3 of the most common symptoms of rectal cancer?

A
  1. Tenesmus
  2. Bleeding
  3. Change in bowel habit
111
Q

What is the precursor lesion to a colorectal carcinoma?

A

Adenoma - forms carcinoma following additional mutations following gross chromosomal alterations

112
Q

What could be a protective treatment against colorectal cancer (not yet rolled out)?

A

Aspirin taken regularly - cox inhibition

113
Q

What are 10 factors that increase risk of developing colorectal cancer?

A
  1. Age >50 - more polyps with age
  2. Obesity
  3. Red meat, processed meat in diet
  4. Alcohol
  5. Smoking
  6. Radiation
  7. Inflammatory bowel disease
  8. Diabetes
  9. Anal cancer risk associated with HPV infection - mainly HPV 16 and 18
114
Q

What are 4 factors that could decrease risk of colorectal cancer?

A
  1. Exercise
  2. Screening
  3. Dietary: antioxidants, dairy products, fibre
  4. Folic acid/ aspirin
  5. Calcium and vitamin D
115
Q

What are the risks of developing colorectal caner with a)UC and b) Crohn’s compared to the general population?

A

a) 30x greater
b) 10-20x greater

116
Q

What is the precusor lesion of the majority of colorectal cancers?

A

Adenomatous polyps:

  • benign glandular polyps
  • sporadic or inherited (FAP)
  • single or multiple
117
Q

What are 3 types of adenomatous polyps (precursor to colorectal cancers)?

A
  1. Tubular adenomas
  2. Tubulo-villous adenomas
  3. Villous adenomas
118
Q

What are 4 risk factors in adenomatous polyps associated with cancer?

A
  1. Multiple polyps
  2. Polyps size more than 10mm
  3. Villous adenoma
  4. High grade dysplasia
119
Q

What is the commonest colorectal cancer tumour type and what proportion does this account for?

A

Adenocarcinoma, 90%

120
Q

What are 4 uncommon subtypes of colorectal cancer tumour?

A
  1. Mucinous carcinoma
  2. Signet ring cell carcinoma
  3. Small cell endocrine carcinoma
  4. Squamous / adenosquamous carcinoma
121
Q

What is the single most independent prognostic factor for colorectal cancer?

A

Lymph node involvement (but also differentiation, depth of invasion)

122
Q

What does the image show?

A

Familial adenomatous polyposis - multiple polyps, mucosal surface covered with small polyps

123
Q

What blood test is often used to check/follow the presence of colorectal cancer?

A

CEA (carcino-embryonic antigen): protein produced by some bowel cancers

124
Q

When is the CEA blood test used in colorectal cancer management?

A

Baseline reading taken at diagnosis, can be used to see if treatment is working and assess for recurrence

125
Q

Why isn’t CEA blood test used to diagnose colorectal cancer?

A

Some bowel cancers don’t produce it so would get a false negative, when it doesn’t always actually exclude cancer

126
Q

What are 3 baseline blood tests to perform when investigating for colorectal cancer?

A
  1. FBC: anaemia
  2. LFT: metastasis to liver
  3. CEA
127
Q

What are 5 investigations that can be performed to diagnose colorectal cancer?

A
  1. Colonoscopy ± biopsy - this with a biopsy is most ideal investigation
  2. Rigid sigmoidoscopy ± biopsy
  3. Flexible sigmoidoscopy
  4. Barium enema
  5. Imaging to identify presence of mets
128
Q

What might be needed if a colonoscopy biopsy is not possible to diagnose colorectal cancer?

A

CT-guided biopsy

129
Q

What are 4 types of imaging tests to identify the presence of metastases in colorectal cancer?

A
  1. CT (GI protocol)
  2. MRI
  3. PET scan
  4. CT colonography (see image)
130
Q

What are the 4 stages to the ‘T’ part of TNM staging for colorectal cancer?

A
  1. T1: tumour only in inner layer of bowel wall: lamina propria up to submucosa
  2. T2: muscle layer - muscularis propria
  3. T3: deeper, serosa
  4. T4: through lining of bowel through bowel wall, may have invaded nearby organs or structures
131
Q

What are the 3 categories of N staging as part of TNM staging for colorectal cancer?

A
  1. N0: no lymph nodes containing cancer cells
  2. N1: 1-3 lymph nodes close to bowel contain cancer cells
  3. N2: 4 or more
132
Q

What are the 2 parts to the M part of TNM staging of colorectal cancer?

A
  1. M0: no spread to other organs
  2. M1: spread to other parts of body
133
Q

How do the 8 stages tie in with the TNM staging for colorectal cancer?

A
  1. Stage 0: Tis, N0, M0
  2. Stage I: T1-2, N0, M0
  3. Stage IIa: T3, N0, M0
  4. Stage IIb: T4, N0, M0
  5. Stage IIIa: T1-2, N1, M0
  6. Stage IIIb: T3-4, N1, M0
  7. Stage IIIc: any T, N2, M0
  8. Stage IV: any T, any N, M1
134
Q

What are 3 staging modalities?

A
  1. CT chest/ abdo/ pelvic
  2. Full bowel examination
  3. MRI pelvis (rectal)
135
Q

What are 4 most common sites of metastatic spread of colorectal cancer?

A
  1. Main duct of lymphatic system
  2. Lungs
  3. Heart
  4. Liver
136
Q

What proportion of patients with colorectal cancer present with metastatic disease?

A

20%

137
Q

Of those paitents who are diagnosed with early stage colorectal cancer, what proportion will suffer from disease recurrence?

A

20%

138
Q

What are 5 kinds of specialist nurses who may be involved in the care of a patient with colorectal cancer?

A
  1. Oncology nurse specialist
  2. Clinical nurse specialist
  3. Colorectal nurse specialist
  4. Stoma nurse
  5. Chemotherapy nurse
139
Q

The presence of what mutation in colorectal cancer can influence treatment decisions?

A

Presence of EGFR mutation

140
Q

Why might a patient with coloerectal cancer receive neoadjuvant chemotherapy?

A

Downstage tumour to ensure clear surgical margins

141
Q

Why might a patient with colorectal cancer receive adjuvant chemotherapy following surgery?

A

To maximise chance for cure, especially if high risk of recurrence e.g.:

  • positive surgical margins
  • lymphovascular invasion
  • tumour perforation
  • poorly differentiated grade III type tumour
  • invasion of adjacent organs
142
Q

When is palliative chemotherapy given in colorectal cancer and why?

A

When cancer cannot be removed, to delay or reverse cancer-related symptoms and improve quality and length of life

143
Q

What is the mainstay of chemotherapy treatment for colorectal cancer based around?

A

5-FU (fluorouracil): thymidylate synthetase inhibitor (antimetabolite), blocks synthesis of thymidine - nucleic acid required for DNA replication

144
Q

In addition to 5-FU, what are 3 other examples of chemotherapy drugs given in colorectal cancer?

A
  1. Capecitabine
  2. Oxaliplatin
  3. Irinotecan
145
Q

What is the only time radiotherapy is really used in colorectal cancers?

A

Before or after surgery in rectal cancer

146
Q

What are biological agents in the treatment of colorectal cancer?

A

Targeted therapies, work through specific pathways involved in cancer growth to attack cancer cells directly

147
Q

What are 2 examples of biological agents that can be used to increase survival in colorectal cancer?

A
  1. VEGFR inhibitors e.g. bevacizumab, aflibercept: disrupts tumour blood supply
  2. EGFR inhibitors e.g. cetuzimab and panitumumab, only if NO mutation in EGFR receptor; acts on commonly disrupted pathway in colon cancer
148
Q

What is the typical follow up of patients with colorectal cancer, following chemotherapy?

A
  • seen alternating between oncologists and surgeons in outpatient clinic every 3 months then extended to 6 months, then every 12 months
  • clinical exam, history, blood tests inc CEA
  • colonoscopy 1 year after removal then annually for 5 years
  • surveillance colonoscopy every 3-5 years to identify new polyps and/or cancers
  • Annual CT
149
Q

What do many patients with colorectal cancer die from (present in 50%)?

A

Liver metastases

150
Q

What is ERAS?

A

Enhance recovery after colorectal surgery

151
Q

What are 2 operative elements of ERAS?

A
  1. Minimally invasive/tranverse incisions
  2. Epidural/ low opiate use
152
Q

What are 4 post-operative elements of ERAS?

A
  1. Rapid mobilisation
  2. Early feeding
  3. No NGT/ drains
  4. Restricted IV fluids
153
Q

What are 4 things that ERAS leads to, inc. cost effects and staff involved?

A
  1. Decreased length of stay
  2. Decreased septic complications
  3. Probably cost neutral (?)
  4. Team approach

AIP: Diarrhoea (8 decks)

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