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