Choong Young Kim

Volumetric analysis and indocyanine green retention rate at 15 min as predictors of post‐hepatectomy liver failure

OBJECTIVES The actual future liver remnant (aFLR) is calculated as the ratio of remnant liver volume (RLV) to total functional liver volume (TFLV). The standardized future liver remnant (sFLR) is calculated as the ratio of RLV to standard liver volume (SLV). The aims of this study were to compare the aFLR with the sFLR and to determine criteria for safe hepatectomy using computed tomography volumetry and indocyanine green retention rate at 15 min (ICG R15). METHODS Medical records and volumetric measurements were obtained retrospectively for 81 patients who underwent right hemi-hepatectomy for malignant hepatic tumours from January 2010 to November 2013. The sFLR was compared with the aFLR, and a ratio of sFLR to ICG R15 as a predictor of postoperative hepatic function was established. RESULTS In patients without cirrhosis, the sFLR showed a stronger correlation with the total serum bilirubin level than the aFLR (R(2) = 0.499 versus R(2) = 0.239). Post-hepatectomy liver failure developed only in the group with an sFLR of <25%, regardless of ICG R15. In patients with cirrhosis, the aFLR and sFLR had no correlation with postoperative total serum bilirubin. An sFLR : ICG R15 ratio of >1.9 showed 66.7% sensitivity and 100% specificity. CONCLUSIONS Regardless of ICG R15, an sFLR of ≥ 25% in patients without cirrhosis, and an sFLR of ≥ 25% with an sFLR : ICG R15 ratio of >1.9 in patients with cirrhosis indicate acceptable levels of safety in major hepatectomy.

A comparison between surgical resection and radiofrequency ablation in the treatment of hepatocellular carcinoma

Purpose The aim of this study was to compare the therapeutic effects of radiofrequency ablation (RFA) and hepatic resection (HR) with regards to procedural morbidity, mortality, overall survival (OS) and disease-free survival (DFS) rates in hepatocellular carcinoma (HCC) patients. Methods Retrospective studies were performed based on the medical records of 129 patients who underwent curative HR, and 57 who patients received RFA for HCC, between 2005 and 2009. The inclusion criteria of HCC were the presence of three or fewer nodules 3 cm or less in diameter or a single nodule of 5 cm or less. Results The 1-, 3- and 5-year OS rates in the HR group were 91.3%, 78.8%, and 64.9%, compared to 94.4%, 74.0%, and 74.0% in the RFA group, with no significant difference between the two groups (P = 0.725). The estimated 1- and 3-year DFS rates were 70.0% and 53.0% in the HR group and 65.2% and 24.7% in the RFA group, respectively. The DFS rates of HR group were significantly higher than RFA group (P = 0.015). Multivariate analysis identified that recurrence (P = 0.036) and portal hypertension (P = 0.036) were associated with OS and that portal hypertension (P = 0.048) and increased serum α-FP (P = 0.008) were the factors significantly associated with DFS. Conclusion HCC within Milan criteria should consider hepatectomy as the primary treatment if the patients liver function and general conditions are good enough to undergo surgical operation. But in that RFA revealed similar overall survival to HR, RFA can be an alternative therapy for patients who are eligible for surgical resection.

Collision tumor of the ampulla of Vater - Coexistence of neuroendocrine carcinoma and adenocarcinoma: report of a case

Herein, we present a case of coexisting neuroendocrine carcinoma and conventional adenocarcinoma (collision tumor) in the ampulla of Vater, which has seldom been reported in the literature. A 51-year-old man presented with a month history of jaundice. MRCP disclosed about 1.9×1.8 cm sized heterogeneously enhancing mass in ampulla of Vater, causing obstructions of distal common bile duct. He underwent pylorus-preserving pancreaticoduodenectomy under the diagnosis on ampulla of Vater cancer. Pathologically, sections on the ampulla of Vater showed conventional ductal adenocarcinoma extended and collided with poorly differentiated neuroendocrine carcinoma. In conclusion, we hereby presented a case of coexisting neuroendocrine carcinoma and conventional adenocarcinoma in the ampulla of Vater.

Neurodegeneration of Drosophila drop‐dead mutants is associated with hypoxia in the brain

The Drosophila drop‐dead (drd) mutant undergoes massive brain degeneration, resulting in sudden death. drd encodes a multi‐pass membrane protein possessing nose resistant to fluoxetine (NRF) and putative acyltransferase domains. However, the etiology of brain degeneration that occurs in drd mutant flies is still poorly understood. Herein, we show that drd neurodegeneration may be because of an oxygen deficit in the brain. We found that DRD protein is selectively expressed in cells secreting cuticular and eggshell layers. These layers exhibit blue fluorescence upon UV excitation, which is reduced in drd flies. The drd tracheal air sacs lacking blue fluorescence collapse, which likely contributes to hypoxia. Consistently, genes induced in hypoxia are up‐regulated in drd flies. Feeding of anti‐reactive oxygen species agents partially rescue the drd from sudden death. We propose that drd flies can provide a non‐invasive animal model for hypoxia‐induced cell death.

Comparison of remnant to total functional liver volume ratio and remnant to standard liver volume ratio as a predictor of postoperative liver function after liver resection.

Backgrounds/Aims The future liver remnant (FLR) is usually calculated as a ratio of the remnant liver volume (RLV) to the total functional liver volume (RLV/TFLV). In liver transplantation, it is generally accepted that the ratio of the graft volume to standard liver volume (SLV) needs to be at least 30% to 40% to fit the hepatic metabolic demands of the recipient. The aim of this study was to compare RLV/TFLV versus RLV/SLV as a predictor of postoperative liver function and liver failure. Methods CT volumetric measurements of RLV were obtained retrospectively in 74 patients who underwent right hemihepatectomy for a malignant tumor from January 2010 to May 2013. RLV and TFLV were obtained using CT volumetry, and SLV was calculated using Yus formula: SLV (ml)=21.585×body weight (kg)0.732×height (cm)0.225. The RLV/SLV ratio was compared with the RLV/TFLV as a predictor of postoperative hepatic function. Results Postheptectomy liver failure (PHLF), morbidity, and serum total bilirubin level at postoperative day 5 (POD 5) were increased significantly in the group with the RLV/SLV ≤30% compared with the group with the RLV/SLV >30% (p=0.002, p=0.004, and p<0.001, respectively). But RLV/TFLV was not correlated with PHLF and morbidity (p=1.000 and 0.798, respectively). RLV/SLV showed a stronger correlation with serum total bilirubin level than RLV/TFLV (RLV/SLV vs. RLV/TFLV, R=0.706 vs. 0.499, R2=0.499 vs. 0.239). Conclusions RLV/SLV was more specific than RLV/TFLV in predicting the postoperative course after right hemihepatectomy. To determine the safe limit of hepatic resection, a larger-scaled prospective study is needed.

Peribiliary cysts developed in normal underlying liver: report of a case.

Peribiliary cysts, known as cystic dilatation, of the extramural peribiliary glands of the bile duct are rare, and are usually detectable under conditions of pre-existing hepatobiliary diseases such as liver cirrhosis. Preoperative diagnosis is often difficult, because they are usually asymptomatic. Distinction of peribiliary cysts from premalignant or malignant cystic lesions is mandatory. Herein, we report a case of peribiliary cyst, which was preoperatively assumed as unilobar Carolis diseases in healthy young patients and briefly discuss the management of the condition.