Clinicopathological study of surgery for pulmonary metastases of hepatoblastoma with indocyanine green fluorescent imaging

Abstract

Background:The prognosis of metastatic hepatoblastoma remains poor; to improve it, pulmonary metastasis must be controlled. Indocyanine green (ICG) fluorescent imaging has been used recently for lung metastasectomy. The objective of our study was to clarify the usefulness of ICG imaging for lung metastasectomy of hepatoblastoma using detailed clinicopathological analysis.Procedure: Patients with hepatoblastoma who underwent resection of pulmonary metastases with ICG fluorescent imaging were studied using a retrospective analysis of clinical information, a review of their surgical records, and a histological analysis of their metastatic nodules.Results: Sixteen patients were enrolled. In total, 61 ICG imaging-guided pulmonary metastasectomies were performed, and 350 ICG-positive and 23 ICG-negative specimens were identified. Tumors were confirmed in 250 of the ICG-positive specimens, including eight nonpalpable nodules, on microscopic examination. ICG-positive and tumor-negative specimens showed histological changes suggesting the regression of a tumor or bloodstream disturbance.Conclusions: Surgical resection is one of the few treatment strategies available to patients with hepatoblastoma with multiple relapses of pulmonary metastasis resistant to chemotherapy. This study demonstrates the high sensitivity of ICG imaging and that thorough metastasectomy can be achieved with ICG imaging. Because a number of false-positive specimens were detected, further optimization of the dose of ICG and the timing of its administration, and establishment of detection of ICG-positive, tumornegative nodules during surgery are important issues. Several false-negative specimens were also detected, suggesting the presence of ICG-negative metastatic tumors. Palpation during surgery and imaging studies remain essential for detecting metastatic lesions, even in the era of ICG imaging.

Feasibility of indocyanine green‐guided localization of pulmonary nodules in children with solid tumors

“…Those studies reported increased ICG uptake and impaired excretion of the fluorophore due to the tumor's biliary characteristics. 2,[22][23][24][25][26][27][28][29] However, the literature lacks information about nonhepatic tumor-related metastases and the feasibility and effectiveness of ICG application in those cases.…”

Indocyanine green navigation in minimally invasive resection of multiple metachronous pulmonary metastases of hepatoblastoma

“…Pulmonary metastatic lesions are easily detected by ICG fluorescence due to the lack of ICG accumulation in normal lung tissue, which results in a clear contrast generated in pulmonary metastases of hepatocyte neoplasic cell such as HBs or hepatocarcinomas 3 . In addition, one of the limitations of ICG fluorescence imaging is its inability to probe deep tissue, as the fluorescence emitted by ICG can only penetrate 5–10 mm of tissue 2 . However, typical HB metastatic lesion location in peripheral pulmonary areas reduces the impact of this drawback 5 .…”

“… 3 In addition, one of the limitations of ICG fluorescence imaging is its inability to probe deep tissue, as the fluorescence emitted by ICG can only penetrate 5–10 mm of tissue. 2 However, typical HB metastatic lesion location in peripheral pulmonary areas reduces the impact of this drawback. 5 Moreover, intraoperative lung collapse by one‐lung ventilation may facilitate detection of the metastatic lesion if it is not near the surface of the lung once the lung has been collapsed.…”

“…Indocyanine green (ICG) is a fluorescent dye that is well absorbed by hepatocyte‐derived neoplastic cells and is excited by infrared radiation at 760 nm, emitting fluorescence at 830 nm. 2 Based on these unique characteristics, it has been applied to detect both liver and metastatic site lesions in HB, 3 , 4 although its utility in minimally invasive surgery has been rarely reported. We present the utility of ICG navigation in thoracoscopic resection of multiple metachronous pulmonary metastasis of HB.…”

Thoracoscopic Resection of Lung Nodules following CT-Guided Labeling in Children and Adolescents with Solid Tumors

“…Preoperative labeling combined with minimally invasive resection of metastases has been developed during recent years to meet these challenges. Different techniques pursuing this approach have been described, some of them also in children [ 7 , 8 , 9 , 10 , 11 , 12 , 13 , 21 , 22 , 23 ]. These methods include labeling with Indocyanine Green (ICG) or other fluorescending agents, radionuclear labeling, or the use of hook wires.…”