Grant 01585: Evaluating a Safer, Less Toxic Radiation Therapy in the Treatment of Lymphoma

Lymphoma is extremely radiosensitive, however, incorporating full and half-body radiation therapy has demonstrated a quid pro quo effect between treatment-related toxicities and tumor control. In human medicine, this approach has been abandoned for advanced IFRT techniques utilizing advanced radiotherapy systems designed to kill residual disease while sparing normal tissues. As the technology becomes available in veterinary medicine, this treatment capability will also become available; however, there are no studies in the veterinary literature specifically interrogating this strategy. While demonstrable benefit is the ultimate clinical endpoint, it is critical to ensure safe implementation of IFRT for use in canine patients.
To test feasibility and safety, we propose a phase I study in which patients with advanced stage lymphoma will be treated with IFRT using helical tomotherapy. Canine patients identified will be treated with our current standard of care, a 19 week multi-drug chemotherapy protocol. Upon completion, they will be anesthetized to undergo CT examination for radiation therapy planning. Enlarged lymph nodes and the spleen and liver will be contoured as targets and treated to a predetermined dose level. Patients will be subjected to rigorous evaluation at each treatment and at one month intervals for dose limiting toxicities and/or adverse events.