1b GI Cancer Flashcards
What is a cancer?
A disease caused by an uncontrolled division of abnormal cells in a part of the body
What is the difference between primary and secondary cancer?
Primary = arising directly from cells in an organ
Secondary = Spread from another organ, directly or by other means (blood and lymph)
What are cancers from squamous epithelium called?
Squamous Cell Carcinoma (SCC)
What are cancers of glandular epithelium called?
Adenocarcinoma
What are cancers of enteroendocrine cells called?
Neuroendocrine tumours (NETs)
What are cancers of the interstitial cells of Cajal called?
Gastrointestinal Stromal Tumours (GISTs)
What are cancers of the smooth muscle called?
Leiomyoma / leiomyosarcomas
What are cancers of the adipose tissue called?
Liposarcomas
What are the three forms of colorectal cancer?
Sporadic
Familial
Hereditary syndrome
Describe the histopathology of colorectal cancer?
Adenocarcinoma
Which type of colorectal cancer is present in older populations, with an absence of family history and generally an isolated lesion?
Sporadic
Which type of colorectal cancer is present with patients with a family history, younger age of onset and specific gene defects?
hereditary syndrome
What can PREVENT the normal epithelium to become hyperproliferative epithelium?
Aspirin and other NSAIDs
Folate
Calcium
Which mutation is involved with the formation of hyperproliferative epithelium?
APC mutation
Which mutation is involved with the formation of A large adenoma?
K-Ras mutation
What STOPS the formation of a large adenoma from a small adenoma?
Oestrogen
Aspirin and other NSAIDs
Which two genetic events result in the formation of a colon carcinoma from a large adenoma?
Loss of 18q
p53 mutation
What are the past history risk factors for colorectal cancer?
Adenoma, ulcerative colitis, radiotherapy
Having which condition in your family history will increase the risk of colorectal cancer?
Peutz-Jegher’s syndrome - rare disorder in which growths called polyps form in the intestines
What are the diet and environmental risk factors for colorectal cancer?
Smoking
Obesity
Socioeconomic status
What are the clinical presentations of caecal and right sided cancer?
Iron deficiency anaemia (most common)
Change of bowel habit (diarrhoea)
Distal ileum obstruction (late)
Palpable mass (late)
What are some clinical presentations of left sided and sigmoid carcinoma?
PR bleeding, mucus
Thin stool - late sign
What are some symptoms of a rectal carcioma?
PR bleeding, mucus
Tenesmus - continutally needing to empty bowels
Anal, perineal, sacral pain (late)
What are some signs of a local invasion?
Bladder symptoms
Female genital tract symptoms
What are some signs of a metastasized colorectal cancer ?
Liver (hepatic pain, jaundice)
Lung (cough)
Regional lymph nodes
Peritoneum - Sister Marie Joseph nodule
What sign indicates metastasis of colorectal cancer?
Sister Marie Joseph Nodule
What are signs of primary cancer?
Abdominal mass
DRE: most <12cm dentate and reached by examining finger
Rigid sigmoidoscopy
Abdominal tenderness and distension – large bowel obstruction
What are some signs of metastasis of colorectal cancer which involve other body systems?
Hepatomegaly (mets)
Monophonic wheeze – lung metastasis
Bone pain
What is the FIT test?
FIT (Faecal Immunochemical Test) - detects minute amounts of blood in faeces (faecal occult blood).
Which tumour marker is a good indicator of colorectal cancer?
Tumour markers: CEA which is useful for monitoring
What is the difference between colonoscopy and FlexiSigmoid?
colonoscopy goes the whole way around, flexi is only in the sigmoid colon
what are the benefits of a colonoscopy?
- visualise lesions
- remove small polyps
- reduce incidence of cancer
Which imaging / investigations is used to visualise lesions that are > 5mm in size?
CT colonoscopy/colonography
What is the benefit of an MRI of the pelvis?
You are able to visualise the depth of invasion, no bowel prep or sedation is involved
What is used to stage colorectal cancer?
CT chest / Abdo / Pelvis
What is the primary management of colorectal cancer?
Surgery
Sometimes stent / radiotherapy / chemotherapy
How is an obstructing colon carcinoma of the right and transverse colon managed?
Resection and primary anastomosis
Extended right hemicolectomy = right colon and portion of the transverse colon is also removed
What is the management of a left sided bowel obstruction?
Hartmann’s procedure
Primary anastomosis
Palliative Stent
Why is there a difference in the right sided and left sided colorectal cancer management principles?
Right sided recieves a good blood supply from the middle colic artery, right colic artery and ileocolic artery,, therefore can resect and anastomose
Left sided blood supply is less good, therefore Hartmann’s procedure needs to be done, along with anastamosis
What type of resection is done when the tumour is in the cecum?
Right hemicolectomy
What procedure is done when the tumour is in the ascending colon - right side?
Right and transverse portion of the colon removed in an extended right hemicolectomy
What procedure is done when the cancer is left sided, in the descending colon?
left side resected