Intraoperative identification of canine hepatocellular carcinoma with indocyanine green fluorescent imaging

Objectives To evaluate the feasibility of high‐sensitivity near‐infrared fluorescence imaging with indocyanine green for intraoperative identification of hepatocellular carcinoma in dogs. Methods Twelve hepatic nodules were surgically resected from six dogs. In each dog, 0 · 5 mg/kg indocyanine green was intravenously injected for 12 to 18 hours preoperatively. The hepatic nodules were investigated under laparotomy using a near‐infrared fluorescence imaging light camera system prior to resection. Resected nodules were histopathologically diagnosed and their fluorescence images were evaluated. Results Of the 12 hepatic nodules, 6 were diagnosed as hepatocellular carcinoma and 6 as nodular hyperplasia. Indocyanine green‐fluorescence was observed in four large hepatocellular carcinoma nodules and one case of nodular hyperplasia, whereas it was absent in the remaining nodules. The sensitivity and positive predictive values of indocyanine green fluorescent imaging for hepatocellular carcinoma was 71 · 4 and 80 · 0%, respectively. Complete resection of the hepatic masses was achieved in all dogs. Clinical Significance Near‐infrared fluorescence imaging may be feasible for intraoperative mapping of hepatocellular carcinomas in hepatic lobes and may help increase the chance of complete resection of hepatocellular carcinoma in dogs.