Share it:

section content

  • Patient is an 11 year and 4 month old male neutered Havanese that presented to the Schwarzman Animal Medical center for chronic vomiting and new hematemesis.
  • Initial workup for chronic vomiting, through the ER, was done a couple of months prior, which included an abdominal ultrasound. The exam revealed mild iliac lymphadenopathy asymmetry (reactivity was considered), bilateral chronic nephropathy and non obstructive nephrolithiasis, and a left adrenal gland nodule (r/o nodular hyperplasia or adenoma). The gastrointestinal tract was normal, enteritis was considered possible.
  • Due to failure to medical management since the initial visit, a repeat ultrasound of the gastrointestinal tract, a gastrointestinal panel and an internal medicine consult for endoscopy/biopsies were recommended. The GI panel revealed an elevated folate (> 24.0 ug/L) which may signify small intestinal bacterial overgrowth or possible EPI and the rest being otherwise normal. A complete blood count and biochemistry revealed a mild lymphocytosis, mild hypocalcemia, and a moderate hypoalbuminemia. Baseline cortisol was normal (4.1 ug/dL).

 

  • Locally extensive gastric wall thickening measures up to 1.2 cm along portions of the gastric cardia and fundus.
  • Wall layering is partial to completely effaced along this portion of the thickened gastric wall.
  • “Pseudolayering” is characterized by a thick hyperechoic and poorly margined band between hypoechoic layers of the gastric wall
  • The mesenteric fat adjacent to this structure is slightly hyperechoic.
  • The stomach wall is otherwise normal, with the stomach containing a mild amount of intraluminal gas. The PDJ, small intestines, ICJ and colon are normal.
  • A mildly enlarged gastric lymph node is observed, measuring 0.5 cm in thickness. This lymph node has mildly rounded margins and is surrounded by mildly hyperechoic fat.
  • Locally extensive gastric wall thickening with loss of wall layering and regional steatitis. A malignant neoplastic etiology (e.g. carcinoma) is prioritized, especially considering the “pseudo layer” appearance. Gastritis is considered less likely but is not entirely excluded.
  • Mildly enlarged gastric lymph node with regional steatitis. Both reactivity and neoplastic infiltration are possible.

In a study focusing on the ultrasonographic findings of canine gastric epithelial neoplasia, thickening of the gastric wall was present in all 16 animals.  Differentials for this thickening included gastric neoplasia, gastric hyperplasia, gastritis, edema or hemorrhage. The majority of the dogs in the study (14/16), a pseudolayered appearance of the wall was found. Histologically, invasive carcinoma was most likely responsible for the uneven and poorly echogenic ultrasonographic pattern of the lesions. The study concluded that a thickened, poorly echogenic gastric wall with associated pseuodlayering and regional or distant lymphadenopathy is highly suggestive of gastric epithelial tumor. Pseudolayer is used in place of “layered wall”, which is reserved for a normal wall appearance. (1).  It has been previously associated with gastric adenocarcinoma and is represented by an alternating hypoechoic and hyperechoic layered appearance of the thickened wall that does not correspond with actual normal histological anatomy (2).

Gastric carcinoma prevalence is low in the canine population (0.16%), with a few breeds having a predilection for the disease (Tervuren, Bouvier des Flandres, Groenendael, collie, standard poodle and Norwegian elkhound) and males having significantly higher odds compared to females. There are multiple subtypes of the gastric carcinoma, adenocarcinoma being the most common. The most common clinical signs include vomiting, anorexia, lethargy, ptyalism, polydipsia and abdominal distension and discomfort (3).

The most common location for canine gastric carcinoma are located in the lesser curvature and pyloric region of the stomach. There is a high rate of metastasis at the time of diagnosis (70-90%), the most common location being regional lymph nodes. Prognosis without treatment is poor, with median overall survival time with metastasis being 33 days (95% Cl 14-578).

The only potential curative treatment option involves surgical resection with wide margins (1-2 cm) however this option is limited based on the common locations of the lesions. Chemotherapy alone or after surgery have been reported. (4).

References:

  1. Penninck, D. G., Moore, A. S., & Gliatto, J. (1998). Ultrasonography of canine gastric epithelial neoplasia. Veterinary Radiology Ultrasound, 39(4), 342–348. https://doi.org/10.1111/j.1740-8261.1998.tb01618.x
  2. Larson, M. M., & Biller, D. S. (2009). Ultrasound of the gastrointestinal tract. Veterinary Clinics of North America: Small Animal Practice, 39(4), 747–759. https://doi.org/10.1016/j.cvsm.2009.04.010
  3. Seim-Wikse, T., Jörundsson, E., Nødtvedt, A., Grotmol, T., Bjornvad, C. R., Kristensen, A. T., & Skancke, E. (2013). Breed predisposition to canine gastric carcinoma – a study based on the Norwegian Canine Cancer Register. Acta Veterinaria Scandinavica, 55(1). https://doi.org/10.1186/1751-0147-55-25
  4. Hugen, S., Thomas, R. E., German, A. J., Burgener, I. A., & Mandigers, P. J. (2016). Gastric carcinoma in canines and humans, a review. Veterinary and Comparative Oncology, 15(3), 692–705. https://doi.org/10.1111/vco.12249

Ultrasound still image of the video shown above. Notice the poorly margined hyperechoic band surrounded by hypoechoic tissue in this thickened portion of the gastric wall (pseudo-layering)

Ultrasound still image of the video shown above. Notice the discrete margins of gastric wall layering without thickening in a region of normal stomach

Image from gastroscopy during biopsy of gastric mass