Adrenal and retroperitoneal neoplasia with invasion of multiple vascular structures

Toy Poodle

12-years-old, Toy Poodle dog. Presented with mass palpable in the abdomen. An abdominal and thoracic CT-scan was performed.

Toy Poodle

Description

There is a large, oval, soft tissue mass (red arrows) with markedly irregular and ill-defined margins, located in the caudal aspect of the retroperitoneum, adjacent and ventral to the abdominal aorta and caudal vena cava. The mass has a markedly heterogeneous soft tissue attenuation with strong and heterogeneous post-contrast enhancement. The mass causes a mild dorsal displacement of the aorta (Ao) and its trifurcation (pink arrows). In addition, the mass causes a severe invasion of the caudal vena cava, which is distended with a large filling defect with an intravenous thrombus, showing the same attenuation and post-contrast enhancement as the mass (blue arrows). The mass also invades both common iliac veins, more prominent and extensive on the right compared to the left (orange arrows).

dog, CT, abdomen, retroperitoneum
dog, CT, abdomen, retroperitoneum
dog, CT, abdomen, retroperitoneum
dog, CT, abdomen, retroperitoneum
dog, CT, abdomen, retroperitoneum

Adjacent to the mass (red arrows), on the left side, there is another oval mass, showing better defined margins and similar characteristics with strong and heterogeneous contrast enhancement, that could be consistent with a severely enlarged left medial iliac lymph node (green arrows).

dog, CT, abdomen, retroperitoneum
dog, CT, abdomen, retroperitoneum

The left kidney is markedly hydronephrotic with a severe distention of the renal pelvis, with preservation of a thin cortex (green arrows). The proximal aspect of the left ureter is also markedly distended, filled with fluid attenuating material up to the level of the mass, where the ureter seems to be embedded within the mass (pink arrows).

dog, CT, abdomen, left kidney

The right adrenal gland is enlarged with well-defined and irregular margins, showing a strong and slightly heterogeneous post-contrast enhancement (orange arrows). The lesion invades the phrenicoabdominal vein, with a filling defect that has the same attenuation as the lesion in the adrenal (blue arrows). It is also in intimate contact with the caudal vena cava causing a mild invasion, with a small and irregular filling defect (purple arrows).

dog, CT, abdomen, right adrenal gland
dog, CT, abdomen, right adrenal gland
dog, CT, abdomen, right adrenal gland

There are multiple small pulmonary nodules, with soft tissue attenuation, showing mild contrast enhancement, spread throughout the lung lobes (orange arrows).

Alt text: dog, CT, thorax, lung lobes
Alt text: dog, CT, thorax, lung lobes
Alt text: dog, CT, thorax, lung lobes

One of the cranial mediastinal lymph nodes is slightly prominent with homogeneous post-contrast enhancement (orange arrows).

dog, CT, thorax, cranial mediastinal lymph node

Diagnosis

  • Mass with aggressive characteristics affecting the right adrenal gland, most likely consistent with malignant neoplasia (primary adrenal tumor – pheochromocytoma or carcinoma vs metastasis from the mass located in the caudal retroperitoneum). The mass causes invasion of the right phrenicoabdominal vein and mild invasion of the cauda vena cava.
  • Mass located in the caudal retroperitoneum, ventral to the aorta and caudal vena cava, infiltrative and with ill-defined margins, most likely consistent with a neoplastic process (retroperitoneal paraganglioma, most likely).

    • The mass severely invades the caudal vena cava and other adjacent vessels, such as both common iliac veins, both deep circumflex iliac veins, median sacral vein and caudal vesical vein.

    • Moderate left hydroureter and marked left hydronephrosis, most likely secondary to invasion/severe compression of the left ureter by the mass.

  • Severe left medial iliac lymphadenopathy most likely consistent with metastasis.
  • Multiple small pulmonary nodules throughout the lung parenchyma, most likely consistent with metastasis.
  • Mild cranial mediastinal lymphadenopathy, most likely consistent with metastasis vs reactive.
BACK

Chronic hepatitis with hepatic cirrhosis and portal hypertension in a dog

7-year-old mixed dog

7-years-old, mixed dog. Presented with vomiting, weight loss and decreased appetite. An abdominal CT-scan was performed.

7-year-old mixed dog

Description

The liver is severely reduced in size, with markedly rounded margins, especially on the left side. The left medial and lateral liver lobes are severely reduced in size, with rounded margins, and homogeneous pre- and post-contrast attenuation (orange arrows). The remaining liver lobes are also decreased in size, although less severely, with a nodular appearance, showing slightly heterogeneous soft tissue attenuation and post-contrast enhancement, with multiple ill-defined hypoattenuating areas (blue arrows).

dog, CT, abdomen, liver lobes
dog, CT, abdomen, liver lobes

The portal vein, at its extra and intrahepatic portions, and the hepatic veins are surrounded by a hypoattenuating halo/region, which is quite severe in the cranial abdomen and less severe in the remaining portions, consistent with severe perivascular oedema (green arrows). 

dog, CT, abdomen, portal vein
dog, CT, abdomen, portal vein
dog, CT, abdomen, hepatic and renal vessels

Adjacent to the hepatic vessels, in the left cranial abdomen, there is a small network of tortuous vessels, without being able to follow its path, consistent with gastroesophageal varices (purple arrows). In addition, there is a small network of tortuous vessels in the region surrounding the cranial mesenteric artery and renal vessels, medial to the left kidney, consistent with gastrophrenic varices (red arrows).

dog, CT, abdomen, hepatic and renal vessels
dog, CT, abdomen, hepatic and renal vessels

The pancreas is slightly prominent with a hypoattenuating halo and multiple hypoattenuating stripes consistent with pancreatic oedema (orange arrows).

dog, CT, abdomen, pancreas

Some of the mesenteric lymph nodes (hepatic, splenic and colic lymph nodes – blue, orange and green arrows respectively) are slightly prominent, decreased in attenuation and with reduced post-contrast enhancement

dog, CT, abdomen, mesenteric lymph nodes
dog, CT, abdomen, mesenteric lymph nodes
dog, CT, abdomen, mesenteric lymph nodes

There is a scant amount of peritoneal fluid surrounding the abdominal organs, visible between the intestinal loops (green arrows). In addition, the peritoneal fat has a diffusely and slightly increased attenuation, with presence of fat stranding (blue arrows).

dog, CT, abdomen, intestinal loops
dog, CT, abdomen, intestinal loops

Diagnosis

  • Severely reduced in size liver (left side>right) with nodular appearance, with rounded margins and areas of heterogeneous attenuation. These changes are most likely consistent with hepatic cirrhosis, most likely secondary to chronic hepatitis. Associated with these changes, there are changes consistent with portal hypertension:
    • Very severe perivascular oedema surrounding the portal vessels and hepatic vein.
    • Pancreatic and mesenteric oedema.
    • Presence of gastrophrenic and gastroesophageal varices, consistent with acquired portal collateral circulation.
    • Scant amount of peritoneal effusion.
  • Mild mesenteric lymphadenopathy, which could be reactive associated with the hepatic abnormalities vs edematous lymph nodes secondary to portal hypertension cannot be excluded.
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