Clinical
presented here, abnormalities, other than slight resistance to
insufflation, were not detected on endoscopic examination.
Biopsies of stomach wall taken at the time of endoscopic
examination were normal. Diagnosis of gastric carcinoma was
suspected on ultrasonographic examination and confirmed on
histological examination, indicating gastric neoplasia may be
missed on endoscopy. Neoplastic cells did not infiltrate the
mucosa in this case and thus were unable to be detected on
endoscopic examination.
Abdominal lymphadenopathy was not identified on
ultrasonographic examination and at surgery lymph nodes were
within normal limits. Ultrasonographic detection of enlarged
regional lymph nodes is a frequent finding in dogs with gastric
neoplasia,7 due to a high incidence of metastatic spread.
Regional or distant lymphadenopathy is associated with a poor
prognosis. 4
,8
,6
Survey and contrast radiographic examination may aid
diagnosis of suspected gastric neoplasia, however, findings may
be subtle or nonspecific. Survey abdominal radiographs rarely
reveal features indicative of gastric neoplasia, except for
2
occasional thickening or roughening of the gastric wall. If the
lesion extends into the gastric lumen it will be seen as a filling
defect. Ulceration may be seen on contrast radiographs as an
interruption of the smooth interface. The ulcer itself appears as a
3
‘smudge’ or ill-defined collection of barium in the lesion.
Pathology of musculature of the stomach results in ‘stiffness’ or
3
non-distensible, thickened regions. In the dog presented here
Figure 4. Histological section showing anaplastic carcinoma
cells infiltrating between smooth muscle fibres in the gastric
wall. Note that some of these cells have cytoplasmic clearing
consistent with the production of mucus. [HE, x 250)
there was wide infiltration of muscle. Although this dog was not
examined by fluoroscopy, the appearance of the stomach wall
changed in each radiograph and thus did not have the static
appearance suggestive of abnormal rigidity or stiffness.
Fluoroscopic examination may have aided the diagnosis of
gastric neoplasia in this case.
This case demonstrated that endoscopy may not provide the
diagnosis in all cases of vomiting, anorexia and weight loss
caused by gastric neoplasia. Ultrasound examination provided
information regarding the gastric wall and should be considered
as part of the work up in any case of chronic vomiting.
wall, with loss of layers and enlarged regional lymph nodes, is
suggestive. The most common ultrasonographic finding is
8
transmural thickening associated with altered wall layering as in
the case presented here. Altered layering and hypoechoic
thickening of the gastric wall relates to histological findings of the
tumour arising from submucosa with wide infiltration of muscle.
Regional or distant lymphadenopathy was not seen in the case
presented here. The lymph nodes were within normal limits at
exploratory laparotomy and biopsies were not performed.
References
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clinicopathological study of 11 cases. J Small Anim Pract 1989;30:353-360.
carcinoma include gastric ulceration and rugal abnormalities.2,6
The mucosal surface may lack normal brightness, with apparent
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2
blanching and absence of blood vessels in the submucosa. In
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6
one study 31 cases of canine gastric carcinoma were described.
Twenty-three dogs were examined using a fibre-optic
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in two dogs of gastric carcinoma. Of the remaining two animals,
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findings were not recorded. Eighteen dogs had distinct ulcers. In
five cases without any ulceration, the rugal pattern was diffusely
absent and accompanied by an apparent blanching of mucosa
5
. Sullivan M, Miller A. Endoscopy (fibreoptic) of the oesophagus and stomach in
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8
. Penninck DG, Moore AS, Gliatto J. Ultrasonography of canine gastric
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. Crystal MA, Pennick DG, Matz ME et al. Use of ultrasound guided fine needle
2
with loss of submucosal vascular pattern. In another study, 11
9
cases of canine gastric carcinoma were described. Fibre-optic
examination allowed diagnosis in all dogs, based on the
classification used in human endoscopy.2 Diagnosis was
confirmed by biopsy in seven cases, one was suspicious and in
three cases insufficient material was obtained. In these latter
dogs, the diagnosis of gastric carcinoma was confirmed at
necropsy. Others also consider endoscopy to be the method of
aspiration and automated core biopsy for the diagnosis of gastrointestinal
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1
0. Penninck DG, Nyland TG, Fisher PE, Kerr LK. Ultrasonography of the
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4
choice for diagnosing gastric tumours. However, in the case
(Accepted for publication 25 January 2001)
3
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Aust Vet J Vol 79, No 5, May 2001