Seminars in Avian and Exotic Pet Medicine最新文献

Lymphoma is the most common malignant neoplasm of ferrets. Older ferrets are typically affected with a chronic, lymphocytic form of lymphoma, whereas juvenile ferrets more often acutely develop a lymphoblastic form. Lymphoma in ferrets can affect any organ but most often involves the spleen, liver, lymph nodes, thymus/mediastinum, and kidneys. No definitive cause for lymphoma in ferrets has yet been identified; however, cluster outbreaks of lymphoma among cohabitating ferrets suggest an infectious (possibly viral) etiology. This article reviews potential causes of lymphoma in ferrets. Typical clinical signs depending on tumor location are discussed. Common diagnostic findings are presented, including results of radiographic and ultrasonographic studies, hematology, and histopathologic examination. Treatment options for ferret lymphoma, including chemotherapy and radiation, are outlined.

Photodynamic therapy (PDT) is a novel form of treatment for solid cancers. It relies on the systemic administration of a light-reactive drug (photosensitizer) to the patient. Through various mechanisms, the photosensitizer localizes to the malignant tissue. The photosensitizer is then activated by visible red light, often provided by a laser. The drug and light alone do not cause tissue damage; when the photosensitizer, light, and molecular oxygen are present together, the reactive oxygen species generated locally lead to apoptosis, vascular stasis, and subsequent ischemic necrosis, and inflammation. PDT is potentially useful for the treatment of exotic animals, because it has fewer adverse effects than radiation therapy or chemotherapy. Because PDT is typically a single session, there are fewer issues with repeated general anesthesia and vascular access. To date, experiences with PDT in exotic animals are limited, but preliminary reports suggest it will become a useful treatment in these species. Further knowledge of photosensitizer pharmacokinetics and tumor biology in exotic animals will be necessary to develop PDT into a useful cancer treatment modality.

There is little information in the literature regarding the use of chemotherapy to treat cancer in exotic animals. This article provides a historical perspective on the use and utility of the body surface area scheme for dosing chemotherapy in animals. Normogram-based recommendations for arriving at a proper chemotherapy dose for the management of cancer in exotic animals are made. It is realistic to offer treatment for many neoplastic diseases in exotic animal species, as long as the limitations are realized and informed consent of the owner is obtained.

Radiation therapy has long played a significant role in the treatment of cancer in people, dogs, and cats. Recently, this technology has been applied to small mammal, avian, and reptile species with some success. Radiation therapy may play an important role in the control of locally aggressive tumors and has been used in both definitive and palliative settings. However, there are some special challenges that must be overcome to successfully treat these species with radiation therapy and, in many cases, little is known about the natural behavior of the tumors being treated. This article introduces some of the basic tenets of radiation oncology, while addressing some of the aspects of radiation biology that are problematic when treating very small or air-filled patients. Much work needs to be done to define fractionation schemes and field geometries that will allow avian and exotic pets to be safely and effectively irradiated.