Genetic alteration of SLCO1B3 defines constitutional indocyanine green excretory defect in patients who underwent hepatectomy.

AIM: Constitutional indocyanine green (ICG) excretory defects must be distinguished when assessing liver function. The absence of OATP1B3 expression due to homogenous alterations in the SLCO1B3 gene has been recently reported to induce ICG excretory defects; however, its association with the clinical examinations and the clinical implications of heterogeneous SLCO1B3 gene alteration remain unclear. METHODS: OATP1B3 expression was evaluated in 49 patients who underwent hepatectomy after evaluation of the ICG retention rate at 15 min (ICGR15) and technetium-99 m-galactosyl serum albumin (99mTc-GSA) hepatic scintigraphy. Additionally, alterations in SLCO1B3 were analyzed in patients without OATP1B3 expression. Subsequently, 59 patients who underwent hepatectomy for colorectal liver metastasis (CRLM) were analyzed. RESULTS: Of 49 patients, 6 (12%) had absent OATP1B3 expression. They had significantly higher ICGR15 value (74.7% vs. 23.5%; p < 0.0001), better modified albumin-bilirubin (ALBI) grade (≤grade 2A, 100% vs. 42%; p = 0.010), more normal 99mTc-GSA hepatic scintigraphy (100% vs. 28%; p = 0.0003), and better pathological liver fibrosis (F0-1, 100% vs. 49%; p = 0.027) compared to those with OATP1B3 expression. Three available frozen blocks of cases without OATP1B3 expression showed homozygous alterations in SLCO1B3. Of 59 patients with CRLM in normal liver background, five (8.5%) had heterozygous insertion in SLCO1B3, however they had no difference in ICGR15 values or other clinical findings compared to the other patients. CONCLUSIONS: Constitutional ICG excretory defects may be defined by the complete absence of OATP1B3 expression. The modified ALBI grade and 99mTc-GSA hepatic scintigraphy were useful for detecting constitutional ICG excretory defects.

Reproducibility and efficiency of liver volumetry using manual method and liver analysis software.

BACKGROUND: For liver volumetry, manual tracing on computed tomography (CT) images is time-consuming and operator dependent. To overcome these disadvantages, several three-dimensional simulation software programs have been developed; however, their efficacy has not fully been evaluated. METHODS: Three physicians performed liver volumetry on preoperative CT images on 30 patients who underwent formal right hepatectomy, using manual tracing volumetry and two simulation software programs, SYNAPSE and syngo.via. The future liver remnant (FLR) was calculated using each method of volumetry. The primary endpoint was reproducibility and secondary outcomes were calculation time and learning curve. RESULTS: The mean FLR was significantly lower for manual volumetry than for SYNAPSE or syngo.via; there was no significant difference in mean FLR between the two software-based methods. Reproducibility was lower for the manual method than for the software-based methods. Mean calculation time was shortest for SYNAPSE. For the two physicians unfamiliar with the software, no obvious learning curve was observed for using SYNAPSE, whereas learning curves were observed for using syngo.via. CONCLUSIONS: Liver volumetry was more reproducible and faster with three-dimensional simulation software, especially SYNAPSE software, than with the conventional manual tracing method. Software can help even inexperienced physicians learn quickly how to perform liver volumetry.

Resection and reconstruction of the largest abdominal vein system (the inferior vena cava, hepatic, and portal vein): a narrative review.

Background and Objective: As tumors invade major abdominal veins, surgical procedures are transformed from simple and basic to complicated and challenging. In this narrative review, we focus on what is currently known and not known regarding the technical aspects of major abdominal venous resection and its reconstruction, patency, and oncologic benefit in a cross-cutting perspective. Methods: A systematic literature search was performed in PubMed and Semantic Scholar from inception up to October 18, 2023. We reviewed 106 papers by title, abstract, and full text regarding resection or reconstruction of the inferior vena cava, hepatic vein confluence, portal vein (PV), and middle hepatic vein (MHV) tributaries in living donor liver transplantation (LDLT) in a cross-cutting perspective. Key Content and Findings: The oncologic benefit of aggressive hepatic vein resection with suitable reconstruction against adenocarcinoma remains unclear, and further studies are required to clarify this point. A superior mesenteric/PV resection is now a universal, indispensable, and effective procedure for pancreatic ductal adenocarcinoma. Although many case series using tailor-made autologous venous grafts have been reported, not only size mismatch but also additional surgical incisions and a longer operation time remain obstacles for venous reconstruction. The use of autologous alternative tissue remains only an alternative procedure because the patency rate of customized tubular conduit type to interpose or replace the resected vein is not known. Unlike arterial replacement, venous replacement using synthetic vascular grafts is still rarely reported and there are several inherent limitations except for reconstruction of tributaries of MHV in LDLT. Conclusions: Various approaches to abdominal vein resection and replacement or reconstruction are technically feasible with satisfactory results. Synthetic vascular grafts may be appropriate but have a certain rate of complications.