- Eliot Kaplan, DVM -
Last month I discussed mast cell tumors in dogs. As mentioned, when a mast cell tumor is diagnosed in a dog, it must be treated as a malignant (aggressive) cancer. That means immediate surgical removal. When the tumor is removed, the surgeon should remove healthy tissue around the tumor as well. In other words, healthy tissue up to 1- 3 centimeters beyond the obvious edge of the tumor should be removed to maximize the chances of a surgical cure.
In cats, mast cell tumors on the skin are a different story. In the majority of cases, they are benign---easy to cure with simple surgery. Wide surgical margins are not required. Unfortunately, in rare instances, mast cell tumors in cats can take another form. Instead of developing primarily on the skin, in this form, the tumor develops on the spleen. This can be fatal. Weight loss and poor appetite are the symptoms I see with this form most often. Uncommonly, the tumor on the spleen can discharge tumor cells that settle on the skin resulting in multiple skin mast cell tumors developing as well.
Treatment of choice is to remove the spleen as well as any mast cell tumors on the skin. These cats will often live well for at least 1 year after surgery. Some cats could even be cured by the surgery. Regardless, when a cat is found to have multiple mast cell tumors on the skin, it is a good idea to ultrasound the abdomen of the cast to make sure the spleen is free of tumor. However, even if the spleen is involved, the prognosis for the next year or longer can still be quite good with surgery. |
