GI cancers Flashcards
what is secondary cancer/metastasis
spread to another organ directly or by other means e.g blood or lymph
what are cancers of squamous epithelial cells called
squamous cell carcinoma
what are glandular epithelium cells called
adenocarcinoma
what are enterocendocrine cell tumours called
neuroendocrine tumours
what are interstitial cell of cajal tumours called
gastrointestinal stromal tumours
GISTs
what are smooth muscle cell cancers called
leiomyoma/ leiomyosarcomas
what are adipose tissue cancers called
liposarcomas
describe squamous cell carcinomas in oesophageal cancers
arise from normal oesophageal squamous epithelium at upper 2/3
caused by acetaldehyde pathway (alcohol)
more common in less developed world
describe adenocarcinoma in in oesophageal cancer
occur in lower 1/3 of oesophagus
from metaplastic columnar epithelium
related to acid reflex
more common in more developed world
what is oesophagitis
inflammation
caused by GORD - 30% of uk population
what is barrets oesophagus
metaplasia - potential for cancer
of 30% with oesophagitis 5% will get barrets
what is the bsg guidelines for barrets surveillance
no dysplasia - every 2-3 yrs
lgd - every 6 moths
hgd - intervention
what is the male:female ratio for adenocarcinoma of oesophagus
10:1
what are some common facts of og cancers
late presentation- dysphagia and weightloss 65% palliative high morbidity and complex surgery poor 5 yr survival <20% palliation = difficult
how to diagnose og cancers
endoscopy and biopsy
how can you stage cancers
ct scan
laparoscopy
eus?
pet scan? - to pick up matastases
treatment plan for patients with og cancers
curative = neo adjuvant chemo radical surgery palliative = dxt stent chemo
what is an oesophagectomy
remove upper part of stomach and oesophagus
rejoin
what is colorectal cancer
epidemiology
most common gi cancer in western societies
3rd most common cancer death cause in men and women
lifetime risk 1/10 men and 1/14 women
generally affects patients >50yrs
what are the form of colorectal cancers
sporadic - absence of family history, older population and isolated lesion
familial - family history, higher risk if index case is young < 50yrs and relative is close(1st degree)
hereditary syndrome - family history, younger age of onset, specific gene defects e.g fap, hnpcc/lynch sydrome
what is the usual histopathology of colorectal cancer
adenocarcinoma
what can stop the progression of polyps to cancers
aspirin
what are the risk factors for colorectal cancers
past history - colorectal cancer
adenoma,uc, radiotherapy
family history - 1st degree relative <55 yrs
relative with genetic predisp
diet/environmental - carcinogenic foods, smoking, obesity, socioeconomic status
where are the locations of colorectal cancers
2/3 in descending colon and rectum
1/2 in sigmoid colon and rectum - within reach of flexible sigmoidoscopy
what are the clinical presentations/ symptoms of caecal and right sided cancer
iron def anaemia
change of bowel habit - diarrhoea
distal ileum obstruction - late
palpable mass
what are the clinical presentations with left sided and sigmoid carcinoma
pr bleeding , mucus
thin stool - late
what are the clinical presentations of rectal carcinoma
pr bleeding, mucus
tenesmus
anal, perineal and sacral pain - late
what can you see with late local invasion
bladder symtoms
female genital tract symptoms
what are late metastasis clinical presentations
liver - hepatic, jaundice
lung
regional lymph nodes
peritoneum
what are the signs of primary cancer
abdominal mass
dre most <12cm and reached by examining finger
rigid sigmoidoscopy
abdominal tenderness and distension - large bowel obstruction
what are the signs of metastasis and complications in colorectal cancer
hepatomegaly
monophonic wheeze
bone pain
investigations for colorectal cancer
fit( faecal immunochemical test) - detects minute amounts of blood in faeces (faecal occult blood)
guaiac test (hemoccult) - based on pseudoperoxidase activity of haematin
diet restrictions - avoid red meat, melons, horse radish, vit c and nsaids for 3 days before test
blood tests- fbc: anaemia, haematinics - low ferritin
tumour markers -cea useful for monitoring
what is the best way to find /diagnose colorectal tumours
colonoscopy - can visualise lesions <5mm small polyps can be removed reduce cancer incidence usually performed under sedation
why are ct coloscopy/ colonography preferred for elderly
can visualise lesions>5mm
no need for sedation
less invasive and better tolerated
if lesions identified patients needs colonscopy for diagnosis
other imaging techniques for colorectal cancer
rectal cancer - mri pelvis
- depth of invasion, mesorectal lymph node involvement
no bowel prep or sedation required
helps to choose between preoperative chemoradiotherapy or straight to surgery
ct of chest/abdo/pelvis - staging prior to treatment
how is colon cancer managed
primary managed by surgery
stent/radiotherapy/chemotherapy?
how to manage obstructing colon carcinoma
right and tranverse colon - resection and primary anastomosis left handed obstruction - - hartmanns procedure proximal end colostomy \+- reversal in 6 months primary anastomosis - intraoperative bowel lavage with primary anastomosis - defunctioning ileostomy palliative stent
epidemiology of pancreatic cancer
relatively common and highly lethal commonest form is pancreatic ductal adenocarcinoma 80-85% have late presentation 15-20% have resectable disease higher in western countries rare before 45 4th most common cancer
risk factors for pancreatic cancer
chronic pancreatitis type2 dm cholelithiasis, previous gastric surgery and pernicious anaemia diet occupation smoking 7-10% have family history
mutation in genes found in hereditary pancreatitis
prss1
spink1
cftr
pathogenesis for pancreatic cancer
commonest - pancreatic intraepithelial neoplasias
pdas evolve through non invasive neoplastic precursor lesions
panINs are microscopic <5mm diameter
acquire clonally selected genetic and epigenetic alterations
clinical presentation of pancreatic cancer in head of pancreas
jaundice - >90% due to invasion/progression of cbd
often painless
palplable bladder - courvoisers sign
wightloss - anorexia, malabsorption,diabtetes
pain - 70% at time of diagnosis
epigastrium
radiates to back 25%
gi bleeding if duodenal invasion or varices secondary to portal/splenic vein occlusion
clinical presentation of carcinoma of body/tail of pancreas
develops insidiously and asymptomatic in early stages
at diagnosis - more advsnced than lesions at head
marked weight loss with backpain in 60% of patients
jaundice = uncommon
vomiting sometimes occurs in late stage
most unresectable at time of diagnosis
how to investigate pancreatic cancers
mri imaging - detects and predicts resectability with accuracies similar to ct
mrcp - provides ductal images without complications of ercp
ercp- confirms typical ‘double duct’ sign
aspiration/brushing of bile duct system
therapeutic modality - biliary stenting to relieve jaundice
eus - highly sensitive in detection of small tumours
assessing vascular invasion
fna
laparoscopy and laparoscopic us
pet
how to manage pancreastic cancer
hop resection
top resection
4 reasons for liver operations
hepatocell cancer
cholangiocarcinoma
gallbladder cancers
colorectal cancer
aetiology of primary liver cancer (hepatocellular cancer)
70-90% have underlying cirrhosis
aflatoxin
median survival without treatment = 4-6mths
gallbladder cancer aetiology
unknown gs? porcelain gb chronic typhoid infection median survival without treatment 5-8 mths systemic chemotherapy is ineffective
aetiology of cholangiocarcinoma
psc and uc liver fluke - clonorchis sinesis choledochal cyst median survival without treatment ~ <6m systemic chemotherapy ineffective
