Pulmonary carcinoma with metastasis in a cat

Domestic Long Hair Cat

9-years-old, domestic long-haired cat. Presented for weight loss, decreased appetite, lethargy, with elevated respiration rate and coughing episodes. A thoracic CT-scan was performed.

Domestic Long Hair Cat

Description

There is a mass like lesion, with irregular and ill-defined margins affecting the entire right accessory lung lobe and infiltrating the left caudal lung lobe (red arrows). This lesion has soft tissue attenuation, showing a slightly heterogeneous contrast enhancement. The lesion is visible as a consolidated area with presence of multiple air bronchograms embedded within the lesion, causing a mild mass effect over the lobar bronchi of the left caudal lung lobe, which is laterally displaced.

cat, thorax, lung lobe
cat, thorax, lung lobe
cat, thorax, lung lobe
cat, thorax, lung lobe

From left to right: pre and post-contrast images

In addition, the right middle and caudal lung lobes (blue and pink arrows respectively) are completely consolidated, with a slightly increased volume and presence of air bronchograms, with similar appearance compared to the previously described lesion. Cranial to this region, there is a subpleural lesion connecting with the right caudal lung lobe, which seems to infiltrate the caudal aspect of the right cranial lung lobe (yellow arrows). These lung lobes have a soft tissue attenuation with a mild and slightly heterogeneous contrast enhancement.

cat, thorax, lung lobe
cat, thorax, lung lobe
cat, thorax, lung lobe

In addition, at the aerated portions of the left caudal lung lobe, there are multiple, variable in size, ill-defined nodular lesions (pink arrows).

cat, thorax, lung lobe
cat, thorax, lung lobe

There is a moderate/marked enlargement of the tracheobronchial lymph nodes (green arrows), which show a reduced homogeneous contrast enhancement.

cat, thorax, lymph nodes
cat, thorax, lymph nodes

Diagnosis

  • Complete consolidation of the right middle, caudal and accessory lung lobes associated to a mass-like lesion, partially infiltrating as well the left caudal lung lobe and possibly the right cranial lung lobe. These findings are most likely consistent with a neoplastic process (primary pulmonary tumor – carcinoma, among others).
  • At least 3 small nodules in the left caudal lung lobe, adjacent to the previously described lesion, consistent with metastatic disease, most likely.
  • Moderate tracheobronchial lymphadenopathy, most likely metastatic.

Thyroid carcinoma with severe pulmonary metastasis in a dog.

7-years-old, French Bulldog. Respiration improved after BOAS surgery, but recently has become noisier. A CT-scan of head, neck and thorax was performed.

Description

In the right cranial cervical region, there is a soft tissue attenuating mass with heterogeneous attenuation, showing marked heterogeneous post-contrast enhancement (red arrows), located in the anatomical location of the right thyroid, which is not visible. The mass is highly infiltrative, with ill-defined margins.

dog, neck, cervical
dog, neck, cervical
dog, neck, cervical
dog, neck, cervical

The mass severely invades the adjacent soft tissues invading the cranial trachea (pink arrows), the laryngeal wall (purple arrows) and the wall of the cranial esophageal sphincter (blue arrows).

dog, neck, trachea, larynx, oesophagus
dog, neck, trachea, larynx, oesophagus
dog, neck, trachea, larynx, oesophagus
dog, neck, trachea, larynx, oesophagus

The right retropharyngeal lymph node is severely enlarged with homogeneous post-contrast enhancement (blue arrows).

dog, neck, lymph nodes
dog, neck, lymph nodes

In the thorax there is a thrombus that extends along the cranial vena cava slightly invading the right atrium (red arrows).

dog, thorax, vena cava, right atrium

There are several small soft tissue nodules, with well-defined margins, spread throughout the lung parenchyma. They show marked heterogeneous post-contrast enhancement.

dog, thorax, lung parenchyma
dog, thorax, lung parenchyma
dog, thorax, lung parenchyma
dog, thorax, lung parenchyma

Diagnosis

  • Large mass highly infiltrative with aggressive characteristics located in the right cranial cervical region at the anatomical location of the right thyroid, consistent with a neoplastic process (infiltrative thyroid carcinoma, most likely).
  • Marked right retropharyngeal lymphadenopathy, consistent with metastasis.
  • Multiple pulmonary nodules, consistent with severe pulmonary metastasis.

Lobar pneumonia with abscess caused by inhalation of a foreign body in a dog.

2-years-old, mixed breed dog. Presented for coughing episodes and suspected abscess caused by foreign body. A thoracic CT-scan was performed.

Description

The accessory lung lobe is almost entirely consolidated, being increased in attenuation with presence of an air bronchogram at its dorsal and medial aspect and a cavitary lesion at its ventral aspect. The area of alveolar pattern shows a slightly heterogeneous enhancement (blue arrows). The cavitary lesion presents multiple cavities within it that appear to be connected with each other, with fluid attenuating, non-contrast enhancing material and multiple gas bubbles, being surrounded by a thick capsule that shows marked post-contrast enhancement (red arrows). These lesions are in close contact with the diaphragm and with the cardiac silhouette in the region adjacent to the left ventricle. The caudal vena cava (CVC) is located to the right of the consolidated lobe, in intimate contact with the area of alveolar pattern, without being in contact with the cavitary lesion or involved in it.

dog, CT, thorax, lung lobe
dog, CT, thorax, lung lobe
dog, CT, thorax, lung lobe

In the left caudal lung lobe, there is a focal and tubular bronchiectasis of the lobar bronchus up to its most peripheral aspect (blue arrows) with the bronchus correctly aerated. In its more peripheral aspect, at the most caudodorsal aspect of the lung lobe, associated to the area of bronchiectasis, there is a focal area with slightly ill-defined margins, increased attenuation (pink arrows) associated with a pleural band (orange arrows), causing a small indentation on the surface of the lung lobe.

dog, CT, thorax, lung lobe
dog, CT, thorax, lung lobe
dog, CT, thorax, lung lobe
dog, CT, thorax, lung lobe

In the left caudal lung lobe, there is a focal and tubular bronchiectasis of the lobar bronchus up to its most peripheral aspect (blue arrows) with the bronchus correctly aerated. In its more peripheral aspect, at the most caudodorsal aspect of the lung lobe, associated to the area of bronchiectasis, there is a focal area with slightly ill-defined margins, increased attenuation (pink arrows) associated with a pleural band (orange arrows), causing a small indentation on the surface of the lung lobe.

dog, CT, thorax, lymph nodes
dog, CT, thorax, lymph nodes
dog, CT, thorax, lymph nodes

Diagnosis

  • Alterations in the right accessory lung lobe consistent with lobar pneumonia and abscess most likely associated with inhaled foreign body, even if the foreign body is not clearly visible in the CT. Consider that, given that the lesion consistent with an abscess is in intimate contact with the diaphragm and the cardiac silhouette, the presence of adhesions in these structures cannot be ruled out.
  • Alterations in the left caudal lung lobe, at its caudodorsal aspect, consistent with pneumonic focus with pleural adhesion and bronchiectasis of the main bronchus, associated with migration of the inhaled foreign body.
  • Mild sternal and tracheobronchial lymphadenopathy, most likely reactive.