E495
Lumps and Masses

Introduction: Detecting some sort of bump or mass on an animal is one of the most troublesome situations encountered by a pet owner. Questions arise concerning what type of mass it might be: Could the mass be cancerous?  Are there other masses?  What should I do?  Peace of mind and answers to these questions can be found through the help of a veterinarian.

This dog has a skin condition on the underside of the chin and neck called cutaneous lymphoma.

Some important facts that should be realized include the following:
  1. The most common bumps or masses found in small animals are abscesses (infection pockets), tumors, hematomas (blood mass), cysts, warts, granulomas (a type of inflamed tissue, usually chronic in nature), enlarged lymph nodes, or scar tissue. Most of these are not life threatening and are easily treated.
  2. Any fast-growing mass, regardless of size, should receive immediate attention.
  3. Tumors can be benign (less invasive, less destructive) or malignant (invasive, destructive, and may spread to other locations).
  4. Many benign tumors do not cause a problem unless they physically interfere with normal movement/function or they become infected/ulcerated. If necessary, these benign tumors are often easily removed through surgery.
  5. Many malignant tumors are treatable through surgery, chemotherapy, and radiation.

The following information can be very helpful when discussing a mass with a veterinarian:

  1. How long has the mass been present? (It is very important for a veterinarian to know the length of time a mass has been present. Many bumps or masses are difficult to recognize, however, and may have been present long before they were noticed.)
  2. Are there any other masses?
  3. Has there been any injury to the particular area in the past?
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  4. Does the mass come and go?
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  5. Does it seem painful or uncomfortable to the pet?
  6. Has there been any drainage from the area?
  7. Are there any other problems that have been noticed in the pet? These problems may or may not seem to be related to the mass (trouble breathing, increased appetite, or lack of energy).

Diagnosis: After a detailed history has been taken and a physical exam has been performed, some of the following procedures and tests may be required.

  1. X-ray (radiograph) - This procedure gives the health-care professional a deeper look at the involved area. Some tissue and most bone tumors can be identified and evaluated based on X-rays. Radiographs can also help determine whether the mass has spread (metastasized) to other areas of the body. In addition, radiographs can also be very useful in detecting the presence of internal masses, especially in the abdomen or lungs; however, they cannot be used to tell what type of mass is present.
  2. A sample of the mass for observation and analysis may be taken. This can be done in two ways:
  1. In a procedure called a fine needle aspirate, a needle is inserted into the mass and a small sample is removed. Material collected from the needle is then stained and observed under magnification. The staining/magnification process is known as cytology. Cytology is useful in detecting the presence of infection, many types of inflammation, and may also be helpful in diagnosing certain types of cancer.
  2. A second method of taking a sample is called a biopsy. A biopsy involves taking a small sample of the mass using a variety of tools and techniques. Sometimes a mass can be completely re- moved as part of the biopsy procedure. Once a biopsy is taken, the sample is sent to a diagnostic laboratory for microscopic evaluation. Here the tissue is observed microscopically in its natural structure and relationship with surrounding tissue. At this point, a specialist known as a pathologist can often determine the source and identify/ name the mass or lump. To ensure proper treatment and prognosis, it is essential to biopsy a potentially cancerous mass.

Treatment: Therapy for all lumps and masses depends entirely on the diagnosis. This is why diagnostic testing for lumps and masses is of critical importance. Treatment for many masses (some tumors, cysts, warts, scar tissue, and granulomas) requires surgical removal. This is often all that is required and a full recovery can be expected. Malignant tumors most commonly require surgery, chemotherapy and/or radiation. Abscesses should be drained and may require antibiotic treatment. In cases of lymph node enlargement, the cause should be identified and may be treated with antibiotics.

See page F770 for additional information on tumors and masses.