>I local club members' ferret was diagnosed with a brain tumor. FML >archive search and the Fox book proved to be no help. >Anyone with experience/advice for me to forward to the owner? Dear Shari: Before going down the road with brain tumors, which are very uncommon, I generally would ask how that particular diagnosis was arrived at. The problem with a brain tumor diagnosis, is that in most cases, and at most practices, it is a very untreatable diagnosis. However, bacterial meningitis, a far more common problem in ferrets, especially young ones, is a treatable condition and can have identical signs. I have seen a number of cases of meningitis that were diagnosed as brain tumors and not treated, and the animal died of a treatable disease. If you want the hard facts on brain tumors - the most common type in ferrets is lymphoma, followed by astrocytoma. Both of these tumors affect the brain itself, and the tumor, as it grows, destroys the part of the brain that it occupies. Because their distribution is variable, the clinical signs generally vary due to it location, and are referrable to the affected site (for example, if the bottom of the brain is affected, an animal may go blind as a presenting sign.) One type of brain tumor in ferrets, a meningioma, actually arises in the coverings overlying the brain, and compresses the brain. Surgery can be performed on these tumors at specialy hospitals, usually universities, and good results can be had, but at a steep financial cost. Seizures are probably the most common presenting sign of brain tumors in ferrets. However, seizures may also result from insulinoma (most commonly) or from epilepsy (not very common). Insulinoma is easily diagnosed, epilepsy is not (and is usually diagnosed from a response to antconvulsant therapy.) T oday, probably the most definitive non-invasive test for the presence of a brain tumor is a CAT scan (which is available at many university veterinary schools). I approach the diagnosis of a brain tumor with great care, as many practices are not equipped to see inside the black box of the skull. Make sure that all treatable diseases have been ruled out, because a brain tumor in a ferert generally has very limited treatment options. With kindest regards, Bruce Williams, dVM [Posted in FML issue 3236]