Abstract: Objective:To investigate the clinical application of indocyanine green (ICG) near infrared fluorescence imaging in the surgical treatment of hepatocellular carcinoma (HCC).
MethodThe prospective study was adopted. The clinicopathologic data of 24 patients with HCC who underwent surgical resection at the General Hospital of PLA from October 2014 to February 2015 were collected. Intravenous injection of ICG (0.5 mg/kg) was performed before surgery (range, 20.0-120.0 hours, mean, 47.5 hours). After free liver in open surgery, tumor lesions were displayed by fluorescent detector probe and completely resected under the guidance of the probe. The residual liver in vivo was detected, especially resection margin, and rapid frozen pathological examination of suspected lesions were conducted during operation. Fluorescence imaging of isolated tumor specimens was performed, the results of which were analyzed with results of pathological examination. Fluorescence imaging characteristics of the preoperative tumor, new lesions and isolated tumor specimens were observed. The followup using outpatient examination and telephone interview was performed for 1 year up to October 2015. The enhanced rescan of computed tomography (CT) and laboratory reexamination were performed every 3 months, and recurrence rate and mortality were recorded. Measurement data with normal distribution were represented as average (range).
Result: (1) Twentyfour primary lesions in 24 patients were detected by preoperative imaging examination. Of the 24 primary lesions, 19 showed fluoresce on the liver surface with an average depth of 0.36 cm (range, 0.00-0.65 cm) and an average diameter of 6.20 cm (range,1.20-9.00 cm）, 5 didn't show fluoresce with an average depth of 1.52 cm (range, 0.90-2.60 cm) and an average diameter of 4.60 cm (range, 1.50-7.80 cm). (2) Thirteen new suspicious lesions were detected in the residual liver, with an average depth of 0.30 cm (range, 0.00-0.60 cm) and an average diameter of 0.65 cm (range, 0.20- 1.20 cm). The results of intraoperative rapid frozen pathological examination showed that cirrhotic liver nodule was diagnosed in 4 patients, cancer in 3 patients (1 with highdifferentiated tumor and 2 with moderatedifferentiated tumor), dysplasia in 2 patients, inflammatory changes in 2 patients and fatty degeneration in 2 patients. (3) Isolated tumor specimens from 24 patients were cut along the center, with strong fluoresce on the sections. Eleven highdifferentiated tumors showed tumor tissue imaging, 2 of 9 moderatedifferentiated tumors showed tumor tissue imaging and 7 of 9 moderatedifferentiated tumors showed annular fluorescent imaging of tumor peripheral tissue, 4 poordifferentiated tumors showed annular fluorescent imaging of tumor peripheral tissue. (4) All the 24 patients were followed up for 1 year without death, and 3 of 24 patients had tumor recurrences with an average recurrence time of 8.3 months (range, 5.0-11.0 months) and received comprehensive treatment as the main treatment of surgery.
Conclution: ICG mediated near infrared fluorescence imaging during the surgery can not only display the primary tumor location clearly, but also detect small lesions which are invisible by routine preoperative imaging examination or during operation, with an advantage of complete tumor clearance.