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Mast Cell Tumor (Mastocytoma) in Dogs

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Manipulation of the tumor may result in the release of histamines from the tumor due to the mast cells releasing from the tumor into the blood stream. Antihistamines may be prescribed to alleviate some of the symptoms related to this effect. This same behavior can come into play as a result of surgical intervention; antihistamines will be used under the circumstances, as a large release of histamines on the body can have a drastic effect on the organs.


Aggressive surgical removal of the mast cell tumor and surrounding tissue is generally the treatment of choice. A microscopic evaluation of the surgically removed tissue is essential for determining the success of the surgical removal and for predicting the biological behavior of the tumor; if tumor cells extend too close to the surgical margins, your veterinarian will need to perform a more aggressive surgery as soon as possible. In case of lymph-node involvement with no generalized involvement in other parts of the body, aggressive surgical removal of the affected lymph node(s) and the primary tumor will be required; follow-up chemotherapy is useful for the prevention of further metastasis of tumor cells.


If the primary tumor and/or affected lymph nodes cannot be excised entirely, chemotherapy may have short-term benefit, with some respite from the effects of the disease. Your dog may have a brief recovery period of one to four months.


If there is a generalized spread of tumor cells to other parts of the body, surgical removal of the primary tumor and affected lymph nodes are of minimal benefit, but chemotherapy may have short-term benefit (less than 2 months). Radiation therapy is a good treatment option for mast cell tumor of the skin in a location that does not allow aggressive surgical removal; if possible, surgery will be performed before radiation therapy is given to reduce the tumor to a microscopic volume; tumors on an extremity often respond better than tumors located on the trunk.


Living and Management


Your veterinarian will want to microscopically evaluate any new masses and evaluate the lymph nodes at regular intervals in order to detect spread of Grade 2 or Grade 3 tumors. Your doctor will also want to perform a complete blood count at regular intervals if your dog is receiving chemotherapy. Immunity can be affected by cancer fighting drugs, so it will be important to protect your dog from illness and communicable diseases during this period, as well as sticking closely to a healthy, immune boosting diet.




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