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Mammary Gland Tumor in Cats




Each cat needs to be thoroughly evaluated before a treatment plan is made since aggressive treatment may not be the best option. However, research and advances in treating mammary tumors continue.


The treatment of choice is surgical removal of the mass and significant surrounding tissue. Depending on the stage of the mammary tumor and area affected, the veterinarian may advise that the regional lymph nodes or additional mammary glands be removed at the time of surgery. One side of the mammary chain (i.e., all mammary tissue on the right or left side) may be removed to prevent further risk to the tissue. Bilateral mastectomies are difficult, but may also be advised to prevent local spread.


In addition, chemotherapy can be used as a treatment. General health factors must be considered in any treatment plan, and consulting with a veterinary oncologist is helpful. 


Living and Management


Making the cat comfortable during the remainder of its life is an important goal in treatment. Medications that limit pain or anxiety associated with the mammary tumors may be prescribed. Frequent check-ups are important to identify if the cancer has returned or metastasized.




By spaying cats before the age of six months, the risk of mammary cancer is limited considerably. Less is known about spaying older cats with mammary gland tumors, but it is usually recommended.

Image: g215 via Shutterstock


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