gastrointestinal cancers Flashcards
what is cancer?
a disease caused by uncontrolled division of abnormal cells ina part of the body
what is primary cancer
arising directly from the cells in an organ
what is a secondary cancer?
spread to another organ, directly or by other means
cancer of glandular epithelium
adenocarcinoma - most common
most common cancer of GI tract type? not location
adenocarcinoma
cancer of squamous epithelium?
SCC squamous cell carcinoma
cancer of enteroendocrine cells
neuroendocrine tumours (NETs)
cancer of interstitial cells of Cajal
gastrointestinal stromal tumours (GISTs)
cancer of smooth muscle
leiomyoma
leiomyosarcoma
cancer of adipose tissue
liposarcomas
epidemiology of oesophageal squamous cell carcinoma?
upper 2/3 of oesophagus
acetaldehyde pathway (alcohol related)
less developed world
epidemiology of oesophageal adenocarcinoma?
arises from metaplastic columnar epithelium lower 1/3 of oesophagus related to acid reflux more developed world elderly male 10.1 female
how does reflux lead to cancer?
oesophagitis (GORD)
Barretts (metaplasia)
dysplasia (low-high grade)
adenocarcinoma (neoplasia)
what are the surveillance rules for Barretts oesophagus?
no dysplasia - 2/3 years
low grade dysplasia - 6monthly
high grade dysplasia - interventions
how do oesophageal cancers often present?
LATE with dysphagia and weight loss
therefore 65% palliative
poor 5 year survival
how are survival rates for oesophageal adenocarcinoma?
65% palliative cases
high morbidity, high risk surgeries
less than 20% 5 year survival
what is the diagnosis process for oesophageal cancer?
2wk cancer referral service
endoscopy and biopsy
how is staging for oesophageal cancer determined?
primarily CT scan CAP
possible laparoscopy or PET scan (usually done as upper GI malignancy more aggressive than lower)
what is the curative treatment plan for oesophageal cancer?
neo-adjuvant chemotherapy then radical surgery (two stage Ivor Lewis Oesophagectomy)
what is a Two stage Ivor lewis oesohagectomy?
removal of oesophagus and stitch it to stomach
palliative treatment for oesophageal cancer?
chemo
DXT (anti-cancer agent)
stents
what are the forms of colorectal cancer
usually all adenocarcinomas
sporadic
familial
hereditary syndrome
what is sporadic colorectal cancer?
absence of FH, older population, isolated lesion
what is familial colorectal cancer?
FH, high risk if index case is under 50 and 1st degree relatives
what is hereditary syndrome colorectal cancer?
FH, younger age of onset, specific gene defects (FAP, HNPCC/Lynch syndrome)
FAP - familial adenomatous polyposis HNPCC - hereditry nonpolyposis colorectal cancer
what is the epidemiology of colorectal cancer?
most common GI cancer western 3rd highest death rates of cancer 1in 10 men 1 in 14 women generally over 50s
what are the risk factors for colorectal cancer?
PMH colorectal cancer, adenoma, UC, radiotherapy
FH 1st degree relatives, genetic predispositions
environment carcinogenic food, smoking, obesity, socioeconomic status
what is the disease process for colorectal cancer?
normal epi (APC mutation) hyperproliferative epi, abberant cryptic foci (COX-2 overexpression) small adenoma (K-ras mutation) large adenoma (p53 mutation, loss of 18q) colon carcinoma +invasion
what is the most common location for colorectal cancer presentation?
2/3 desc colon, rectum
1/2 sigmoid colon, rectum
how does caecal and right sided colorectal cancer present?
iron deficiency anaemia bowel habit change - diarrhoea distal iluem obstruction (late) palpable mass (late)
how does left sided and sigmoid colorectal cancer present?
PR bleeding
mucus in stool
thin stool (late)
how does rectal colorectal cancer present?(rectal carcinoma)
PR bleeding mucus tenesmus - want to open bowels but nothing released anal, perineal and sacral pain (late) bowel obstruction (late)
what are the symptoms of local colorectal cancer invasions?
bladder symptoms
female genital tract symptoms
what are the locations and symptoms of metastasis of colorectal cancer?
liver - hepatic pain, jaundice (very far along)
lung - cough, monophonic wheeze
regional lymph nodes - swelling
perioneum - sister mary joseph nodule (at umbilicus)
bone pain
what are the examinations for a primary colorectal cancer?
abdominal mass, tenderness and distention (large bowel obstruction)
digital rectum exam - most under 12cm dentate
rigid sigmoidoscopy
what are the investigations for colorectal cancer?
faecal occult blood - Guaiac test (haemoccult), faecal immunochemical test FBC colonoscopy CT colonoscopy MRI pelvis for rectal cancer CT chest/abdo/pelvis (for staging)
what are the faecal occult blood tests for colorectal cancer?
Gaiac test - based on pseudoperoxidase activity of haematin
sensitivity 40-80%, specificity 98%
dietary restrictions of red meat, melon, horseradis, vit C and NSAIDs 3 days before
faecal immunochemical test - detects minute amounts of blood in faeces
what can blood tests show for colorectal cancer?
anaemia - low ferritin
tumour marker CEA for monitoring - not diagnostic
how can colonoscopy aid colorectal cancer diagnosis?
visualise lesions smaller than 5mm
removal of small polyps - reduced cancer incidence
how can CT colonoscopies aid colorectal cancer diagnosis?
visualise lesions larger than 5mm
less invasive and better tolerated
but if lesions identified, patient needs colonoscopy for diagnosis
how do MRI pelvis help with rectal carcinoma?
depth of invasion and mesorectal lymph involvement shown
no bowel prep necessary
helps choose between preoperative chemoradiotherapy vs straight to surgery
how is colorectal cancer typically managed?
by surgery
maybe by stents/radiotherapy/chemotherapy
how is an obstructing colorectal cancer in the right and transverse colon managed?
resection and primary anastamosis - good blood supply, low risk of leaking right hemicolectomy (asc) or extended right hemicolectomy (transverse and asc)
how is an obstructing colorectal cancer in the left side managed?
Hartmann’s procedure - formation of colostomy (colon goes straight to skin, rectum sealed off) reversible
or Primary anastamosis - 10% leakage
Palliative stent
why is management of right sided colorectal cancer easier than left sided?
right side blood supply - right colic artery, middle colic artery, ileocolic artery
left side blood supply - left colic
resection dependent on blood supply which is weaker on LHS
rectum also very weak supply
what is the most common form of pancreatic cancer? (not location)
pancreatic ductal adenocarcinoma
risk factors for pancreatic cancer
chronic pancreatitis T2DM smoking family history occupation - insecticides, nickel etc
pathogenesis of pancreatic cancer
non-invasive neoplastic precursor lesions
acquire genetic and epigenetic alterations along the way to become cancer
from PanIN-1A - PanIN-3
clinical presentation of pancreatic cancer - head
most common location
jaundice - painless, palpable gallbladder
weight loss - anorexia, malabsorption and diabetes
pain - epigastrium - back
signs of advanced head of pancreas cancer
persistent vomiting due to duodenal obstruction
gastrointestinal bleeds - duodenal invasion or varices secondary to portal or splenic vein occlusion
clinical presentation of pancreatic cancer - tail and body
insidious marked weight loss back pain jaundice uncommon vomiting very late stage - DJ flexure
investigations for pancreatic cancer
tumour marker CA19-9 ultrasonography dual phase CT MRI MRCP ERCP EUS Laparoscopy PET
importance of tumour marker CA19-9 in pancreatic cancer
greater sensitivity at higher concentrations
falsely elevated in pancreatitis, hepatic dysfunction, obstructive jaundice
ultrasonography findings for pancreatic cancer
dilated bile ducts
liver metastases
can identify tumours
use of dual phase CT in pancreatic cancer
confers resectability in most cases
shows vascular and other organ invasion
distant mets
MRCP and ERCP in pancreatic cancer
MRCP - ductal images wihtout ERCP complications
ERCP - confirms double duct sign, aspiraition of bile-duct system, also therapeutic (biliary stenting - jaundice)
resections of pancreatic cancer
HOP - whipples resection (distal bile duct and gallbladder, distal stomach and duodenum too)
TOP - distal pancreas removed, take out splenic artery and spleen
what is hepatocellular cancer
cancer of hepatic cells
primary liver cancer
where is cholangiocarcinoma most likely to be
bifurcation of common hepatic duct (right/left)
what is cholangiocarcinoma
cancer of bile ducts
what cancer commonly metastasises to the liver
colorectal cancer
what is hepatocellular cancer associated with
underlying cirrhosis
treatment of hepatocellular cancer
liver transplant
trans arterial catheter embolisation
radiofrequency ablation
last 4-6mnth without it, 5yr with
gallbladder cancer associated with
gallstones
porcelain gallstones
chronic typhoid infection
treatment for gallbladder cancer
removal
cholangiocarcinoma associated with
ulcerative colitis and primary sclerosing cholangitis
liver fluke
choledochal cysts
treatment for cholangiocarcinoma
excision
secondary liver cancer treatment
excision
survival 50% possible
history signs of difference between upper and lower oesophageal issues
painful on swallowing - upper
food easy to swallow but feels stuck seconds later - lower
staging investigation for confirmed colorectal cancer
CT chest abdo pelvis
if in doubt about liver, MRI liver
if rectal cancer, MRI of rectum
PET or laparoscopy not required
