Historically, a diagnosis of neoplasia in an exotic animal was made at necropsy or resulted in euthanasia of the animal. Rationale for euthanasia of the animal often included: advanced state of neoplasia at discovery; difficulty in administering and monitoring therapy in zoologic specimens; lack of access to advanced therapies such as radiotherapy; and expense of treatments. If treatment was attempted, it traditionally involved cytoreductive or curative surgical resection of the primary tumor, along with a course of corticosteroid treatment.
With the advent of advanced diagnostic and therapeutic technologies within zoological institutions, including increased preventive medicine examinations with better screening techniques, more options are available for the diagnosis and treatment of neoplasia. Recently, more animals have been treated for malignancies. Current examples include reports of treatment of a tenrec, African lions, a flamingo, a gorilla, a penguin, birds, a ground cuscus, ferrets, a sun bear, and a racer.1-12
Cancers such as lymphoma, mast cell tumor, osteosarcoma, and soft tissue sarcomas may now be more readily managed in zoological animals through minimally invasive procedures in conjunction with operant conditioning. Treatment options for neoplasia are more numerous and advanced than they have historically been, and are becoming more cost-effective. Options range from radiation therapy, intravenous chemotherapy through vascular access ports, oral chemotherapy to biomodulators such as molecularly targeted therapeutics. As zoological medicine continues to trend toward more preventive medicine and increased operant conditioning, prolonging the lives of cancer-affected animals will continue to become a realistic component of zoological medicine.
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