History and Physical Exam: An 11-year-old, castrated male domestic shorthair cat presented for evaluation of a rapidly growing mass along his left rostral maxilla. The owners reported that hyperemia of the mucus membranes had been noticed in that region at his annual physical exam by his local veterinarian. The lesion progressed over the next 5 months and caused loosening of his maxillary canine and incisor teeth. The cat also had a history of hypertrophic cardiomyopathy and hyperthyroidism. Physical examination revealed an approximate 3.5 x 3 x 2 cm gingival mass in the left rostral maxilla displacing the lip. Additional findings included loose teeth, blood-tinged saliva, a moderately enlarged left mandibular lymph node, a palpable thyroid slip and a grade III/VI heart murmur. Continue reading →
The clinical oncology service is comprised of veterinary oncologists, residents and technicians that work together as a team. The oncology service works closely with the surgery service, which has expertise in surgical oncology, as well as with pathology, diagnostic imaging, interventional radiology, and the pain clinic. Through the collaboration with these and other specialty services throughout the hospital, we are able to offer a broad range of options for owners of companion animals with cancer.
As a member of the National Cancer institute’s Comparative Oncology Trials Consortium, as well as through independent studies and collaboration with other veterinary and biomedical institutions, the oncology service is able to offer investigational therapies in addition to conventional treatment.
The oncology service boasts a 6 MV Siemens linear accelerator with 2-16 MeV electrons, a multileaf collimator, and intensity-modulated radiation therapy (IMRT) capabilities. In addition, strontium 90 plesiotherapy is offered, allowing for wide breadth of radiation therapy options. Continue reading →
Every veterinary student knows that lymphoma is the most common hematopoietic neoplasm in dogs and cats. However, we are now recognizing that lymphoma isn’t a single clinical entity. Rather, it is a collection of neoplastic disorders triggered by a myriad of genetic mutations and epigenetic factors that culminate in uncontrolled proliferation of lymphocytes. Multi-institutional collaborative efforts are underway to illuminate the molecular fingerprints of canine and feline lymphomas that will allow for better understanding of the biology of lymphoma as well as improving treatment strategies and outcomes. These benefits are likely to extend across species – even to humans as the field of comparative oncology grows.
Figure 1. Lymphoma in dogs typically presents as generalized peripheral lymphadenopathy. Mandibular swelling due to lymph node enlargement, as shown here, often is a sign that leads clients to seek evaluation.
High-Dose Cyclophosphamide Holds Promise for Dogs with Lymphoma
For decades, the cornerstone of treatment for dogs with lymphoma has been chemotherapy employing five drugs: cyclophosphamide, doxorubicin, vincristine, L-asparaginase and prednisone. Efforts to optimize these protocols by adjusting the doses and scheduling of drugs have not yielded significant improvement in remission rates or survival times. In addition, the realization that discontinuous short chemotherapy protocols are as effective as traditional long protocols that include a lengthy maintenance phase has provided the opportunity to search for novel therapies to combat lymphoma before overt chemotherapy resistance develops.
Alternative modalities that have been studied include radiation therapy, chemotherapy agents traditionally reserved for rescue therapy, monoclonal antibodies, dose-intensified chemotherapy and bone marrow transplantation. These approaches have yielded variable results, and some promising findings are under continued investigation. Continue reading →