world cancer report - iarc

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Fig. 5.24 The mortality from stomach cancer is decreasing worldwide, including in countries with a high
disease burden. D.M. Parkin et al. (2001) Eur J Cancer, 37 Suppl. 8: S4-66.
monotonous diets which are rich in starchy
food pose an increased risk, probably
because they are deficient in the protective
dietary constituents. Many studies
suggest a small increase in risk (about
two-fold) in smokers, but alcohol does not
affect risk, other than at the gastric cardia.
Conditions which cause an excessive rate
of cell proliferation in the gastric epithelium,
thus increasing the chance of fixation
of replication errors induced by dietary and
endogenous carcinogens, include Helicobacter
pylori infection (Chronic infections,
p56), gastric ulcer, atrophic gastritis and
autoimmune gastritis associated with pernicious
anaemia. Gastritis is associated
with increased production of oxidants and
reactive nitrogen intermediates, including
nitric oxide. There is increased expression
of the inducible isoform of nitric oxide synthase
in gastritis. Gastritis and atrophy
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Males
Females
Males
Females
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alter gastric acid secretion, elevating gastric
pH, changing the gastric flora and
allowing anaerobic bacteria to colonize the
stomach.
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Detection
Early stomach cancer is an adenocarcinoma
limited to the mucosa, or the mucosa
and submucosa. It often does not cause
symptoms, although up to 50% of patients
may have non-specific gastrointestinal
complaints, such as dyspepsia. This often
delays the diagnosis of stomach cancer.
Approximately 80% of Western patients
with stomach cancer present to the physician
with advanced tumours, symptoms of
which may include nausea, weight loss,
back pain, epigastric pain, gastrointestinal
bleeding or perforation [3]. Endoscopy and
biopsy is considered to be the most sensitive
and specific diagnostic test for stom-
Fig. 5.26 (A) Endoscopy showing advanced gastric carcinoma in an 80-year-old male patient (ulcerated
tumour without definite limits, infiltrating into the surrounding stomach wall). (B) Corresponding gross
feature of the resected stomach with advanced cancer located in the lesser curvature of the angulus.
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ach cancer. Endoscopic detection of early
lesions may be improved with dyeendoscopy
using indigo carmine, congored,
truigine or methylene blue. Diagnosis
may also be obtained by double-contrast
barium X-ray. Screening for early disease
by X-ray (photofluoroscopy), followed by
gastroscopy and biopsy of suspicious findings,
has been widely used in Japan since
the 1960s. It is a costly approach to prevention,
and the results have been controversial.
Serum pepsinogen screening is a
new and potentially useful method for
detection of stomach cancer [4].
Tumour staging prior to treatment decision
involves percutaneous ultrasound or computed
tomography to detect liver metastases
and distant lymph node metastases
and laparoscopy (with or without laparoscopic
ultrasound) to seek evidence for
peritoneal spread or serosal involvement.
Pathology and genetics
Chronic atrophic gastritis, in particular H.
pylori-associated chronic active gastritis,
Fig. 5.25 Severe atrophic gastritis with intestinal
metaplasia, a risk factor for gastric carcinoma.
Fig. 5.27 Invasive gastric carcinoma: a well-differentiated
trabecular invasive tubular adenocarcinoma.
Stomach cancer
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