Cancer: Mast Cell

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Most commonly, mast cell cancer is either malignant (cancerous) or potentially malignant. The most common locations of mast cell occurrence is on the skin and in visceral (internal) organs.

Some oncogenic viruses, which are viruses that tend to cause tumors, have been identified as possible causes of mast cell cancer in dogs, but most probably it is caused by abnormalities with the immune system. Dogs of any age can develop mast cell cancer, but those age 8 – 10 years are at greater risk.


Clinically, dogs with mast cell cancer mostly exhibit cutaneous (skin) lesions. These initially appear as lumps on the dog skin in the form of nodules. These nodules are raised and soft to solid on palpation (when touched). These tumors vary in size and contain cellular content. Nodules or tumors can occur anywhere on the body, particularly on a dog's trunk, limbs, and inguinal (groin) region. Severe forms of canine mast cell cancer are characterized by ulcerative lesions, with the content of the ulcers flowing consistently flowing out.

Affected dogs will likely experience generalized symptoms as well, which include vomiting, ulcerative pain in the stomach and abdomen. Blood may pass in the feces. A heightened inflammatory response is noted in dogs with mast cell cancer, due to the excessive release of histamine and other factors.


Clinical symptoms can help, but can never be the basis of making a diagnosis. A biopsy by needle aspirate and and microscopic evaluation is required to confirm the presence of the disease. Estimation and evaluation of dog skin lumps and contents in the lumps should be carefully evaluated as to the form and stage of canine mast cell cancer. Based on this analysis, treatment and prognosis.

Different forms of mast cell cancer in dogs are:

  1. Those which occur on the surface of the skin and that are usually benign in nature. These may develop into a malignant form in latter stages. Malignancy is usually restricted to specific areas of the skin, and collectively are less harmful.
  2. This form affects not only the skin but sub–cutaneous tissues (deeper) as well. These too are potentially malignant, and the prognosis is termed “poor” for this form.
  3. These are reported on the skin and in deeper tissues. Mast cell cancers that occur in the visceral (internal) organs are included in this category. These are highly malignant in nature with a "grave" prognosis.

Similarly, four different stages of mast cell cancer in dogs have been defined on the basis of the state of the malignancy.


There are different options for treatment, but the ratio of unpredictable response to existing treatment options is relatively high in cases of mast cell cancer in dogs. Though mast cell cancers are potentially malignant, surgical removal is preferred for the reason that there is a greater chance of elimination plus precision the goes with targeting a specific area with surgery. Curative surgical treatment is possible for stages involving only skin tissues and a single dog skin lump development on the skin.

For other forms, surgical options alone are not enough. Chemotherapy and radiation therapy are other options, which can be combined with surgical elimination. Response to chemotherapeutics is not satisfactory, thus radiation therapy and/or surgical options are made compulsory along with this approach.

For added support after treatment anti-oxidants such as C-Caps Formula could be helpful with symptoms and recovery. Supplements may also be helpful if a dog doesn't undergo treatment, with support focused on extending the dogs lifespan and improving the quality of life as the disease progresses.