Lung Cancer (Squamous Cell Carcinoma) in Dogs

Squamous Cell Carcinoma of the Lungs in Dogs

The epithelium is the cellular covering of all of the internal and external surfaces of the body, protecting the organs, inner cavities and outer surfaces of the body in a continuous layer of multi-layered tissue. The squamous epithelium is a type of epithelium that consists of the outer layer of flat, scale-like cells, which are called squamous cells. A squamous cell carcinoma of the lung is a type of metastasizing tumor that arises from the squamous epithelium in lungs.

This is a rare form of primary tumor with high metastatic potential, especially if it reaches the regional lymph nodes.

Symptoms and Types

• Cough
• Lethargy
• Inability to exercise normally
• Weight loss
• Lameness
• Increased respiration rate
• Coughing up blood

Diagnosis

You will need to give your veterinarian a thorough history of your dog’s health and onset of symptoms. A standard physical examination will include routine laboratory tests, with a complete blood count, biochemical profiles, and urinalysis. The results of the blood tests may reveal an increased number of leukocytes or white blood cells (leukocytosis) in the blood, indicative of an invasion that the body is fighting against. Biochemistry profiles in some patients may show abnormally high levels of calcium (hypercalcemia).

Another diagnostic tool that your veterinarian can use to ascertain your dog’s condition is an endoscope, a minimally invasive tubular device that can be inserted into the body without having to perform surgery in order to view the tumor up close and to take fluid and tissue samples from within the lungs. These samples can then be sent to a veterinary pathologist for further evaluation. The results of this test usually provide an initial diagnosis. Your veterinarian will also take thoracic (chest) X-rays, which may show a single mass arising from a single focus. The trachea may appear to be displaced or compressed due to the presence of a mass, or tumor. In some patients a partial or complete airway obstruction may also be seen.

The only way to confirm a diagnosis of squamous cell carcinoma is to take a lung tissue sample (biopsy). This sample will be sent to a veterinary pathologist, who will cut into very small sections to examine under a microscope.