Predictive risk factors for resection surface-related complications after laparoscopic simultaneous resection of primary colorectal tumor and synchronous liver metastases: a single-center retrospective study.

BACKGROUND: Laparoscopic simultaneous resection (LSR) of primary colorectal tumors and synchronous colorectal liver metastases (sCRLM) has been recently performed. This study aimed to evaluate the postoperative outcomes after LSR and determine the risk factors for resection surface-related complications (RSRC), such as postoperative biliary fistula and liver-transection surface abscess. METHODS: Between 2009 and 2022, consecutive patients with sCRLM who underwent LSR were included. We retrospectively analyzed clinicopathological data, including intraoperative factors and postoperative outcomes. The difficulty level of all liver resections was classified according to the IWATE difficulty scoring system (DSS). We then performed univariate and multivariate analyses to identify the risk factors for RSRC. RESULTS: Of the 112 patients, 94 (83.9%) underwent partial hepatectomy and colorectal surgery. The median DSS score was 5 points (1-11), with 12 (10.7%) patients scoring ≥ 7 points. Postoperative complications were observed in 41 (36.6%) patients, of whom 16 (14.3%) experienced severe complications classified as Clavien-Dindo grade IIIa or higher. There was no postoperative mortality. The most common complication was RSRC (19 patients, 17.0%). Multivariate analysis identified American Society of Anesthesiologists (ASA) classification ≥ 3 [odds ratio (OR) 10.3, 95% confidence interval (CI) 1.37-77.8; P = 0.023], DSS score ≥ 7 points (OR 5.08, 95% CI 1.17-20.0; P = 0.030), and right-sided colectomy (OR 4.67, 95% CI 1.46-15.0; P = 0.009) as independent risk factors for RSRC. Postoperative hospital stays were significantly longer for patients with RSRC than for those without RSRC (22 days vs. 11 days; P < 0.001). CONCLUSION: Short-term outcomes of LSR for patients with sCRLM were acceptable in an experienced center. RSRC was the most common complication, and high-difficulty hepatectomy, right-sided colectomy, and ASA classification ≥ 3 were independent risk factors for RSRC.

Intraoperative artificial intelligence system identifying liver vessels in laparoscopic liver resection: a retrospective experimental study.

BACKGROUND: The precise recognition of liver vessels during liver parenchymal dissection is the crucial technique for laparoscopic liver resection (LLR). This retrospective feasibility study aimed to develop artificial intelligence (AI) models to recognize liver vessels in LLR, and to evaluate their accuracy and real-time performance. METHODS: Images from LLR videos were extracted, and the hepatic veins and Glissonean pedicles were labeled separately. Two AI models were developed to recognize liver vessels: the "2-class model" which recognized both hepatic veins and Glissonean pedicles as equivalent vessels and distinguished them from the background class, and the "3-class model" which recognized them all separately. The Feature Pyramid Network was used as a neural network architecture for both models in their semantic segmentation tasks. The models were evaluated using fivefold cross-validation tests, and the Dice coefficient (DC) was used as an evaluation metric. Ten gastroenterological surgeons also evaluated the models qualitatively through rubric. RESULTS: In total, 2421 frames from 48 video clips were extracted. The mean DC value of the 2-class model was 0.789, with a processing speed of 0.094 s. The mean DC values for the hepatic vein and the Glissonean pedicle in the 3-class model were 0.631 and 0.482, respectively. The average processing time for the 3-class model was 0.097 s. Qualitative evaluation by surgeons revealed that false-negative and false-positive ratings in the 2-class model averaged 4.40 and 3.46, respectively, on a five-point scale, while the false-negative, false-positive, and vessel differentiation ratings in the 3-class model averaged 4.36, 3.44, and 3.28, respectively, on a five-point scale. CONCLUSION: We successfully developed deep-learning models that recognize liver vessels in LLR with high accuracy and sufficient processing speed. These findings suggest the potential of a new real-time automated navigation system for LLR.

[A Case of Curatively Resected Rectal Cancer with Preservation of Urinary Function after Chemotherapy].

A55 -year-old man was diagnosed with rectal cancer invading the urinary bladder and swollen para-aortic lymph nodes. Since distant metastasis was indicated and total pelvic exenteration was required, 6 courses of chemotherapy with mFOLFOX6 plus panitumumab were performed. After the chemotherapy, the rectal cancer and para-aortic lymph nodes significantly decreased in size, and novel distant metastasis was not observed in CT scans. Therefore, the tumor was considered resectable, and operation was performed. Intraoperative frozen section analysis showed that the para-aortic lymph nodes and surgical margin of the urinary bladder were negative. Thus, low anterior resection of the rectum and partial resection of the urinary bladder were performed. R0 resection was pathologically achieved, and adjuvant chemotherapy with S-1 was administered for 6 months. The patient is alive without recurrence for 10 months. Upfront chemotherapy can be a strategy for advanced rectal cancer with urinary bladder invasion to avoid total pelvic exenteration.

Development of X-ray contrast agents using single nanometer-sized gold nanoparticles and lactoferrin complex and their application in vascular imaging.

The technology to accurately image the morphology of tumor vessels with X-ray contrast agents is important to clarify mechanisms underlying tumor progression and evaluate the efficacy of chemotherapy. However, in clinical practice, iodine-based contrast agents present problems such as short blood retention owing to a high clearance ability and insufficient X-ray absorption capacity when compared with other high atomic number elements. To resolve these issues, gold nanoparticles (AuNPs), with a high atomic number, have attracted a great deal of attention as contrast agents for angiography, and have been employed in small animal models. Herein, we developed novel contrast agents using AuNPs and captured changes in tumor vessel morphology with time using X-ray computed tomography (CT). First, glutathione-supported single nanometer-sized AuNPs (sAu/GSH) (diameter, 2.2 nm) were fabricated using tetrakis(hydroxymethyl)phosphonium chloride as a reducing agent. The sAu/GSH particles were intravenously injected into mice, remained in vessels for a few minutes, and were then excreted by the kidneys after 24 h, similar to the commercial contrast agent iopamidol. Next, the Au/GSH and lactoferrin (sAu/GSH-LF) (long axis size, 17.3 nm) complex was produced by adding lactoferrin to the sAu/GSH solution under the influence of a condensing agent. On intravenously administering sAu/GSH-LF to mice, the blood retention time was 1-3 h, which was considerably longer than that observed with iopamidol and sAu/GSH. Moreover, we succeeded in imaging morphological changes in identical tumor vessels for several days using X-ray CT with sAu/GSH-LF.

Living donor liver transplantation for Budd‒Chiari syndrome with right posterior segment graft and patch plasty using the superficial femoral vein: a case report.

BACKGROUND: In living donor liver transplantation (LDLT) for patients with Budd‒Chiari syndrome (BCS), there are several concerns about reconstruction of the inferior vena cava (IVC) and hepatic veins. Herein, we report the case of a patient with BCS who underwent LDLT with right posterior segment graft (RPSG) and patch plasty for reconstruction of the hepatic venous outflow, using the patient's own superficial femoral vein (SFV). CASE PRESENTATION: A 19-year-old man, who was diagnosed with primary BCS, underwent LDLT. His main hepatic veins were totally obstructed, and membranous stenosis was seen in the IVC. The LDLT donor was his mother; however, liver volumetric analysis showed that only her RPSG was appropriate. In the recipient surgery, 16 cm of the left SFV was harvested and was cut longitudinally and opened. The right hepatic vein (RHV) of the RPSG was anastomosed to the sidewall of the SFV graft. After explantation of native diseased liver was completed, the stenotic and thickened wall of the IVC was widely resected, and a large anastomotic orifice was created. Patch cavoplasty was performed with the RHV‒SFV graft patch. After portal reperfusion started, hepatic venous outflow was satisfactory, and there was no venous graft congestion. Both his postoperative course and his long-term course after discharge were uneventful. CONCLUSIONS: In LDLT for BCS patients, ingenuity is required for the reconstruction of venous outflow. The SFV patch can be safely harvested from liver transplant recipients and is suitable for venous reconstruction. In addition, RPSG is an alternative type of liver graft for LDLT if a conventional right- or left-lobe graft cannot be used.

The anti-angiogenic agent lenvatinib induces tumor vessel normalization and enhances radiosensitivity in hepatocellular tumors.

The evaluation of angiogenesis inhibitors requires the analysis of the precise structure and function of tumor vessels. The anti-angiogenic agents lenvatinib and sorafenib are multi-target tyrosine kinase inhibitors that have been approved for the treatment of hepatocellular carcinoma (HCC). However, the different effects on tumor vasculature between lenvatinib and sorafenib are not well understood. In this study, we analyzed the effects of both drugs on vascular structure and function, including vascular normalization, and investigated whether the normalization had a positive effect on a combination therapy with the drugs and radiation using micro X-ray computed tomography with gold nanoparticles as a contrast agent, as well as immunohistochemical analysis and interstitial fluid pressure (IFP) measurement. In mice subcutaneously transplanted with mouse HCC cells, treatment with lenvatinib or sorafenib for 14 days inhibited tumor growth and reduced the tumor vessel volume density. However, analysis of integrated data on vessel density, rates of pericyte-covering and perfused vessels, tumor hypoxia, and IFP measured 4 days after drug treatment showed that treatment with 3 mg/kg of lenvatinib significantly reduced the microvessel density and normalized tumor vessels compared to treatment with 50 mg/kg of sorafenib. These results showed that lenvatinib induced vascular normalization and improved the intratumoral microenvironment in HCC tumors earlier and more effectively than sorafenib. Moreover, such changes increased the radiosensitivity of tumors and enhanced the effect of lenvatinib and radiation combination therapy, suggesting that this combination therapy is a powerful potential application against HCC.

Laparoscopic liver cyst fenestration with real-time indocyanine green fluorescence-guided surgery: a case report.

Laparoscopic fenestration (LF) has recently been considered a standard procedure for nonparasitic symptomatic liver cysts. Here, we report a case of LF that was safely performed using real-time indocyanine green (ICG) fluorescence-guided surgery. A 74-year-old woman presented with right upper abdominal pain and poor dietary intake. The patient was diagnosed with symptomatic liver cysts and underwent LF. One hour before surgery, ICG (2.5 mg) was intravenously administered to the patient. ICG fluorescence imaging clearly showed the biliary ducts and distinguished the cysts from the liver parenchyma. We could resect only the cyst walls as wide as possible under the guidance of both white light and fluorescence imaging. There were no signs of postoperative symptom recurrence. Detection of ICG fluorescence in the liver parenchyma is as important as ICG cholangiography for fenestration. Laparoscopic liver cyst fenestration with real-time ICG fluorescence-guided surgery is safe and can be used as a standard procedure.