Gastric Carcinoma Flashcards
Are peptic ulcers due to cancer?
No, they are a good example of chronic inflammation
What is Zollinger-Ellison syndrome + how does it lead to peptic ulceration?
- tumours from pancreas, stomach or duodenum secrete large amounts of gastrin (gastrinomas)
- cause excess gastric acid secretion
- therefore increased acid attack -> weakened defence system against peptic ulcer
What are complications of peptic ulcers?
- bleeding
- perforation
- stricture formation
- malignant change
How might stricture formation due to peptic ulcer present?
- due to healing of the ulcer by fibrosis
- may present as obstruction
Is the development of carcinoma a common complication of peptic ulcers?
- No, it’s rare
- in fact, it’s now believed that reports of malignant transformation in peptic ulcers probably represents cases in which a lesion thought to be a chronic peptic ulcer was actually an ulcerated carcinoma from start
- ulcerated gastric carcinomas typically have a rolled edge
What investigation should be done from any suspected peptic ulcer in the oesophagus or stomach to rule out that it isn’t actually an ulcerated cancer?
Biopsy
NB. Dudoenal cancer is v rare and so chance of duodenal cancer masquerading as a peptic ulcer is remote. Hence duodenal ulcers do not need to be biopsied to exclude malignancy unless there are worrying endoscopic features.
Who is gastric cancer common in? Has the incidence changed?
- peak incidence in over 50yr age group
- M > F
- incidence has fallen in west over last 50yrs
- reduction due to falling prevalence of H pylori infection and an improved diet
What are important risk factors for developing gastric cancer?
- H Pylori infection (but remember, most ppl w H Pylori infection will not develop cancer)
- cigarette smoking
- alcohol
- diet: food w/ nitrates/nitrite components; salt-based preservatives
- autoimmune gastritis
How might gastric cancer present?
- history of new-onset dyspepsia (esp in a pt >55y)
- unintended weight loss
- progressive dysphagia
- vomiting
- Virchow’s node palpable (left supraclavicular fossa) - Troiser’s sign
What kind of cancer are gastric cancers?
- adenocarcinomas
- arising from glandular mucosa
What are the 2 main types of gastric adenocarcinoma and how do they differ?
- intestinal-type adenocarcinomas - show gland formation, lined by mucus-secreting cells. Better prognosis than diffuse-type (but still poor 5 year survival). Tend to occur in older individuals.
- diffuse-type adenocarcinomas - consist of ‘signet-ring’ cells, with a diffuse pattern of infiltration. Very aggressive -> v bad prognosis. Tends to occur in a younger age group.
They key investigation for gastric cancer is endoscopy and biopsy. What important info does biopsy give us?
- type of cancer (usually squamous cell carcinoma or adenocarcinoma)
- the grade - well, moderately or poorly differentiated
Histology shows signet ring cells, contain large vacuole of mucin which displaces nucleus to one side. Higher number of signet ring cells are associated with a worse prognosis.
How is gastric cancer staged?
- TNM system
- CT or endoscopic USS
- Endoscopic USS superior
- CT CAP first-line staging in most centres
- Laparoscopy to identify occult peritoneal disease
- PET CT (for junctional tumours)
What is the treatment for gastric carcinoma?
- proximally sited disease greater than 5-10cm from O-G jxn may be treated by sub-total gastrectomy
- total gastrectomy if tumour <5cm from O-G jxn
- for type 2 junctional tumours (extending to oesophagus) → oeseophagogastrectomy
- early gastric cancer confined to mucosa → endoscopic sub mucosal resection
- lymphadenectomy D2 nodal dissection
- adjunctive chemotherapy
All pts with gastric cancer are discussed at the MDT meeting to decide on most appropriate treatment: curative or palliative. What is the prognosis of gastric cancer?
- very poor prognosis
- around 5% survival at 5 years
- mainly bc tumour is usually at high stage on presentation
