VX2 rabbit liver tumor model

Male New Zealand white rabbits (2.5–4 kg, Charles River Laboratories) were used in accordance with institutional guidelines under approved Animal Care and Use Committee protocols. Animals were maintained in laminar flow rooms at constant temperature and humidity, with food and water provided ad libitum. Thirty-two rabbits underwent implantation of VX2 tumors in the left lobe of the liver as explained in detail previously (19, 20). Briefly, VX2 tumor chunks were injected into the quadriceps muscle of the hind leg of a donor rabbit and tumors were allowed to grow for 3 weeks. The tumor chunks were harvested from the donor animal and approximately 0.4 mL were injected into the left liver lobe of a recipient rabbit via median laparotomy using a 18G catheter. Abdominal fascias and skin were closed in two layers using absorbable suture materials (chromic gut 3.0; vicryl 4.0). The tumors were allowed to grow for 14 days until a well delineated solitary tumor (1–2.0 cm in diameter) was measurable on CT or MRI (21).

For all surgical interventions, the animals were initially sedated with intramuscular acepromazine 0.25–1 mg/kg and ketamine hydrochloride 30–45 mg/kg. Surgeries and MRI were performed under general anesthesia using isoflurane 1%–3% in oxygen. Supplemental heat support was provided and physiologic monitoring (oxygen saturation, heart rate, and body temperature) was performed during the experiment. Analgesic meloxicam (0.3 mg/kg) and buprenorphine (0.02–0.05 mg/kg) were administered subcutaneously before and after surgical interventions.