Primary Lung Tumors in Dogs (Lung Cancer, Pulmonary Neoplasia)

Primary Lung Tumors in Dogs (Lung Cancer, Pulmonary Neoplasia)

By: Dr. Erika de Papp

Section: Information In-depth

The most common clinical sign seen in patients with lung tumors is a chronic cough. Usually this is a non-productive cough, which means the pet is not coughing up fluid or mucus. Occasionally pets will cough up small amounts of blood. If the tumor is large and is causing compression of the trachea or a major airway, the animal may experience dyspnea (difficulty breathing). Other causes of dyspnea associated with lung cancer include fluid accumulation around the lungs, known as pleural effusion, and widespread cancerous involvement of the lungs, leaving little normal lung tissue.

The clinical signs can also be vague and not specific to the respiratory tract. Up to 25 percent of pets with lung cancer may not show any clinical signs of illness. Occasionally dogs and cats with lung cancer are lame.

This can occur because of spread of tumor to the bones of the limbs (more common in cats), or due to a secondary effect that the tumor has on bone growth (more common in dogs). The latter condition results in excess bone growth and swelling of the limbs, and is referred to as hypertrophic osteopathy. Several other conditions may cause similar clinical signs to those seen in animals with lung cancer. These include:

  • Heart failure. Heart disease and more commonly heart failure, are common causes of chronic coughing in dogs. Dogs that are in heart failure also experience dyspnea due to fluid accumulation in the lungs.

  • Pneumonia. Bacterial infections in the lungs will often cause coughing and dyspnea. This is more common in dogs, but also seen in cats.

  • Metastatic cancer. Cancer that starts in one organ and spreads to other parts of the body is known as metastatic disease. The lungs are a common site of metastasis for many cancers, and the clinical signs may mimic those seen with primary lung tumors.

  • Heartworm infection. Heartworms affect both the heart and the lungs, and may cause coughing and dyspnea in affected animals. This is more common in dogs.

  • Fungal infection. Fungal infections are common in many of the Midwestern, Southeastern, and Southwestern states. Two fungal infections that can severely affect the lungs and produce coughing and dyspnea include Blastomycosis and Coccidioidomycosis. These infections usually affect multiple organ systems and are more common in younger animals.

  • Lungworms. These are parasitic worms that have a predilection for living in the respiratory tract, and can affect both dogs and cats.

  • Collapsing trachea. Physical collapse of portions of the trachea is a common problem in small breed dogs. It causes a characteristic honking cough and may causes episodes of respiratory distress.

    •  
    Printable Version
     
    Have a Pet Question?
    Review the Most Frequent Questions
    Answered by Dr. Jon and His Staff of Veterinarians
    Ask Dr. Jon
    Dr. Jon's Newsletter
    Yes! Send Me the Latest Health Information, Pet Tips, Pet Stories and more...
     
     
     

    Over 10,000 Veterinarian Approved Articles

    Dogs & Puppies
    Cats


    Local Pet Information Guide
     Alabama
     Alaska
     Arizona
     Arkansas
     California
     Colorado
     Connecticut
     DC
     Delaware
     Florida
     Georgia
     Hawaii
     Idaho
     Illinois
     Indiana
     Iowa
     Kansas
     Kentucky
     Louisiana
     Maine
     Maryland
     Massachusetts
     Michigan
     Minnesota
     Mississippi
     Missouri
     Montana
     Nebraska
     Nevada
     New Hampshire
     New Jersey
     New Mexico
     New York
     North Carolina
     North Dakota
     Ohio
     Oklahoma
     Oregon
     Pennsylvania
     Rhode Island
     South Carolina
     South Dakota
     Tennessee
     Texas
     Utah
     Vermont
     Virginia
     Washington
     West Virginia
     Wisconsin
     Wyoming