Pathology: Colorectal Carcinoma Flashcards
what is a polyp?
a protrusion above an epithelial surface
is a polyp benign or malignant?
can be either
name four possible differentials diagnosis of a colonic polyp
adenoma
serrated polyp
polypoid carcinoma
adenocarcinoma
name the three types of appearance a polyp can have
pedunculated
sessile
flat
is adenoma of the colon benign or malignant?
benign
what are most colonic polyps?
adenomas
what are all adenomas?
dysplastic
why do all adenomas need to be removed?
they are all premalignany
what two methods can be used to remove adenomas?
endoscopically
surgically
what is the most common primary treatment for colonic adenocarcinoma?
surgery
what can adenocarcinoma of the colon cause?
ulceration
stricture
perforation
what staging system is used to stage colorectal carcinoma and predict prognosis?
dukes staging
describe a colorectal carcinoma with dukes stage A
confined by the muscularis propria
describe a colorectal carcinoma with dukes stage B
invaded through the muscularis propria
describe a colorectal carcinoma with dukes stage C
has metastasised to lymph nodes
which side of the colon is most commonly affected by colorectal carcinoma?
left
what parts of the colon are affected in left sided colorectal carcinoma?
rectum
sigmoid colon
descending colon
how does left sided colorectal carcinoma present?
blood PR
altered bowel habit
obstruction
what parts of the colon are affected in right sided colorectal carcinoma?
caecum
ascending colon
how does right sided colorectal carcinoma present?
anaemia and weight loss
what three methods of spread can colorectal carcinoma use?
local invasion
lymphatic spread
haematogenous
where can colorectal carcinoma spread via local invasion?
the peritoneum and mesentery
where can colorectal carcinoma spread via lymphatic spread?
mesenteric lymph nodes
where can colorectal carcinoma spread via the haematogenous route?
the liver and other distant sites
name the two inherited colorectal cancer syndromes
hereditary non polyposis coli (HNPCC)
familial adenomatous polyposis (FAP)
what is HNPCC?
hereditary non polyposis coli
how many polyps are present with HNPCC?
less than 100
what method of inheritance is involved with HNPCC?
autosomal dominant
what causes HNPCC?
a defect in DNA mismatch repair
what genes can the mutation for HNPCC be on?
MLH-1
MSH-2
PMS-1
MSH-6
which side is affected by HNPCC?
right side
what response does HNPCC trigger?
a crohn’s like inflammatory response
what other cancers is HNPCC associated with?
gastric and endometrial carcinoma
what is FAP?
familial adenomatous polyposis
how many polyps are there in FAP?
more than 100
which type of inheritance is involved in FAP?
autosomal dominant
what causes FAP?
a defect in tumour suppression
where is the mutation for FAP found?
FAP genes
what type of cancer does FAP cause?
adenocarcinoma
what other tumours is FAP associated with?
desmoid tumours
thyroid carcinoma
