Use Of Imaging-Guided Intensity-Modulated Stereotactic Body Radiation Therapy To Treat A Well-Differentiated Hepatocellular Carcinoma In A Dog

CASE DESCRIPTIONA 14-year-old 5.6-kg (12.3-lb) castrated male Toy Poodle was evaluated because of high serum activities of alkaline phosphatase and alanine aminotransferase and the presence of a hepatic mass.CLINICAL FINDINGSAbdominal CT revealed a large (approx 6.8 X 7.1 X 6.5-cm) soft tissue mass along the midline of the liver. The mass either originated from the papillary process of the caudate lobe or the left medial liver lobe.TREATMENT AND OUTCOMEA partial liver lobectomy was performed, and approximately a third of the mass was successfully removed and submitted for histologic examination. Consultation with the oncology service was advised to determine whether radiation therapy could be used to treat the residual disease. On 5 consecutive days, the dog underwent imaging-guided intensity-modulated radiotherapy-stereotactic body radiation therapy (4 Gy/treatment) with a simultaneous integrated boost to the center of the tumor. The dog received a base dose of 20 Gy that was then boosted to 28 Gy. In the 10-month period after completion of radiation therapy, the hepatocellular mass continued to decrease in size, and overall improvements in the dog's serum liver enzyme abnormalities were evident.