Diseases of Colon & Rectum Flashcards
aetiology of colorectal cancer?
old age, low fibre intake, high fat & sugar intake, obesity, smoking, lack of exercise, long standing inflammatory disease e.g. Crohn’s
modes of cancer spread?
direct, lymphatic, blood (liver, lung)
presentation of colorectal cancer?
anaemia, tiredness, bowel changes, wt loss, rectal bleeding, pain or lump, tenesmus
what is tenesmus?
recurrent need to empty bowels
hx for colorectal cancer?
changes in bowel habits, bleeding from back passage, wt loss, abdominal pain, swelling in abdomen, previous operations?
ix for colorectal cancer?
FOBT (screening), barium enema, rigid sigmoidoscopy/ colonoscopy, CT colonography
how to stage for colorectal cancer using radiology
CT abdo, MRI rectum
what must be done before colonoscopy?
bowel prep, CO2 insufflation, buscopan IV
tx for colorectal cancer?
surgery- right hemicolectom, extended right hemicolectomy, transferase colectomy, sigmoid colectomy, anterior resection, APR post-op staging chemo imaging palliative
what surgical technique is recommended and why?
laproscopy- smaller wound site and faster recovery
what type of palliative care is carried out for colorectal cancer?
stenting, palliative chemo/radio
what are adenomas also known as?
polyps
what is an adenoma?
a protrusion above an epithelial surface
true/false…
polyps are benign
false…
they can be malignant or benign
what are the classes of polyp?
adenoma, serrated polyp, polypoid adenocarcinoma, other
what is an adenoma?
benign tumour but can cause local invasion hence should all be removed
pathophysiology of an adenoma?
normal mucosa > adenoma > large adenoma > adenocarcinoma
what is the tx for polypoid adenocarcinoma?
surgical removal of colon/rectum, radio & chemo
where does polypoid adenocarcinoma usually invade into?
muscularis propria
what is the staging of polypoid adenocarcinoma?
Dukes Criteria
go through Dukes Criteria…
Dukes A: confined by muscularis propria
Dukes B: spread into muscularis propria
Dukes C: metastasis to LNs
recap of TNM staging…?
T: T1 (submucosa), T2 (into muscle), T3 (through muscle), T4 (adjacent structures)
N: N0 (no LNs), N1 (<3LNs) N2 (>3 LNs)
M: M0 (no mets), M1 (mets)
where site is polypoid adenocarcinoma usually found at?
left sided- rectum, sigmoid, descending
what are the common mutations that cause polypoid adenocarcinoma?
APC & K-ras
what nodes are invaded with polypoid adenocarcinoma?
mesenteric
local invasion of polypoid adenocarcinoma?
mesorectum, peritoneum, etc
what is the hereditary cancer causing syndrome?
non polyposis coli (HNPCC)
true/false…
HNPCC presents with <100 polyps
True
describe HNPCC…
right sided, crohn’s like inflammation, late onset
what is the familial cancer causing symptom?
adenomatous polyposis (FAP)
how many polyps does FAP have?
> 100
describe FAP…
early onset, defect in APC tumour suppression gene, throughout colon
what is diverticular disease?
small sacs form in wall of large intestine
why do diverticula form?
high luminal pressure caused by low fibre
what is the epidemiology of diverticular disease?
> 50yo
what is difference between diverticulosis and diverticulitis
diverticulosis: having diverticula (sacs)
diverticulitis: when diverticula become inflamed
aetiology of diverticulitis?
low fibre intake, fatty food, Marfan’s
symptoms of diverticulitis?
LIF pain/tenderness, septic, altered bowel habits
ix for diverticulitis?
exam, barium enema, sigmoidoscopy, CT
what is the diverticulitis scoring system for acute disease?
Hinchey Classification
describe the Hinchey Classification
- para colic abscess
- pelvic abscess
- purulent peritonitis
- faecal peritonitis
tx for uncomplicated diverticulitis
IV antibiotics and inc fibre
tx for complex diverticulitis
Hartmann’s procedure, 1y resection/ anastomosis, percutaneous drainage, laparoscopic lavage and drainage, antibis
what is hartmann’s procedure?
remove sigmoid colon and attach colostomy bag to descending colon
complications of diverticulitis?
pericoli abscess, perforation, haemorrhage, fistula, stricture
what is meckel’s diverticulum?
a result of the incomplete regression of Vitelli-intestinal duct
symptoms of Meckel’s?
asymptomatic
tx for Meckel’s?
laparoscopic resection
when does Meckel’s present?
before 2 years of age- usually incidental finding
what does Meckel’s usually mimic?
appendicitis
complications of Meckel’s?
bleed, perforation, ulceration, diverticulitis, malignant change
what are the types of colitis?
acute or chronic
aetiology of colitis?
infective colitis, ulcerative, crohn’s, ischaemic
what organisms cause infective colitis?
c.dif, campylobacter, shigella, e.coli 0157
what is colitis?
inflammation of colon
symptoms of colitis?
diarrhoea +-blood, cramps, dehydration, sepsis, wt loss & anaemia
ix for colitis?
barium enema*, sigmoidoscopy & biopsy, stool cultures, X-ray
tx for colitis
fluids, IV steroids, GI rest, surgery
who does ischaemic colitis usually affect
elderly and arteriopaths
infection of which artery may result in ischaemic colitis?
infected mesenteric artery
what is colonic angiodysplasia?
submucosal lakes of blood
where does colonic angiodysplasia usually affect?
right side of colon
tx for angiodysplasia?
embolisation, ablation, surgical resection
what are 3 less common bowel diseases?
large bowel obstruction
sigmoid volvulus
pseudomembranous colitis
causes and tx of large bowel obstruction?
colorectal cancer, benign stricture, volvulus.
tx- resuscitate, operate, stent
causes, ix and tx of sigmoid volvulus?
bowel twist on mesentery.
ix- X-ray, rectal contrast
tx- flatus tube, surgical resection
what is most common presentation for pseudomembranous colitis?
massive diarrhoea & vomit
tx for pseudomembranous colitis?
metronidazole/ vancomycin
