Large bowel neoplasia (colon pathology) Flashcards
How prevalent is colorectal cancer?
3rd most common cancer diagnosis
17,000 UK deaths per year
What histological type of cancer is most seen in colorectal cancers?
Adenocarcinomas (98%)
What do most colorectal cancers arise from?
The majority of colorectal cancers arise from polyps (adenomas)
What are the types of polyps/adenomas?
Tubular
Villous
Tubulovillous
Where are tubular polyps most commonly found?
90% in colon
What histological features are seen in low grade dysplasia?
Increased nuclear number
Increased nuclear size
Reduced mucin
What is the spicy way of referring to High grade dysplasia?
Carcinoma in situ
What are the histological features of high grade dysplasia?
Crowded
Very irregular
(+ all the features of LG dysplasia)
What are the risk factors for colorectal cancer?
Lifestyle
Family history
History of / ongoing IBD
Genetics
What types of colorectal cancer arise from genetic problems?
FAP - Familial adenomatous polyposis
HNPCC - Hereditary non-polyposis colorectal cancer
Peutz-Jeghers
Right and left sided colorectal adenocarcinomas have specific shapes
What are these shapes?
Right = Exophytic (outward growing) and polypoid
Left = Annular (ring shaped) - Often called ‘napkin ring lesions’
Which side of colon cancer would be more likely to present with rectal bleeding as a symptom?
Left sided
(left = descending part so blood will flow down)
Anaemia is more strongly linked to which sided colon cancer?
Right sided
What is shown in the photo
Colorectal adenocarcinoma
ie polyp thats become malignant
What factors determine the prognosis of a patient with colorectal cancer?
Tumour grade
Tumour stage
Extramural venous invasion
Suitability for resection
