Prediction of the remnant liver hypertrophy ratio after preoperative portal vein embolization

BACKGROUND

Portal vein embolization (PVE) is considered to improve the safety of major hepatectomy. Various conditions might affect remnant liver hypertrophy after PVE. The aim of the present study was to clarify the factors that affect remnant liver hypertrophy and to establish a prediction formula for the hypertrophy ratio.

METHODS

Fifty-nine patients who underwent preoperative PVE for cholangiocarcinoma (39 patients), metastatic carcinoma (10 patients), hepatocellular carcinoma (8 patients), and other diseases (2 patients) were enrolled in this study. For the prediction of the hypertrophy ratio, a formula with stepwise multiple regression analysis was set up. The following parameters were used: age, gender, future liver remnant ratio to total liver (FLR%), plasma disappearance rate of indocyanine green (ICGK), platelet count, prothrombin activity, serum albumin, serum total bilirubin at the time of PVE and the maximum value before PVE (Max Bil), as well as a history of cholangitis, diabetes mellitus, and chemotherapy.

RESULTS

The mean hypertrophy ratio was 28.8%. The 5 parameters detected as predictive factors were age (p = 0.015), FLR% (p < 0.001), ICGK (p = 0.112), Max Bil (p < 0.001), and history of chemotherapy (p = 0.007). The following prediction formula was established: 101.6 - 0.78 × age - 0.88 × FLR% + 128 × ICGK - 1.48 × Max Bil (mg/dl) - 21.2 × chemotherapy. The value obtained using this formula significantly correlated with the actual value (r = 0.72, p < 0.001). A 10-fold cross validation also showed significant correlation (r = 0.62, p < 0.001), and a hypertrophy ratio <20% was predictable with a sensitivity of 100% and a specificity of 90.9%. Moreover, technetium-99m-diethylenetriaminepentaacetic acid-galactosyl human serum albumin scintigraphy showed a significantly smaller increase in the uptake ratio of the remnant liver in patients with prediction values <20% than in those with values ≥20% (6.8 vs. 20.8%, p = 0.030).

CONCLUSIONS

The prediction formula can prognosticate the hypertrophy ratio after PVE, which may provide a new therapeutic strategy for major hepatectomy.

Impact of sarcopenia on survival in patients undergoing living donor liver transplantation

Skeletal muscle depletion, referred to as sarcopenia, predicts morbidity and mortality in patients undergoing digestive surgery. However, the impact on liver transplantation is unclear. The present study investigated the impact of sarcopenia on patients undergoing living donor liver transplantation (LDLT). Sarcopenia was assessed by a body composition analyzer in 124 adult patients undergoing LDLT between February 2008 and April 2012. The correlation of sarcopenia with other patient factors and the impact of sarcopenia on survival after LDLT were analyzed. The median ratio of preoperative skeletal muscle mass was 92% (range, 67-130%) of the standard mass. Preoperative skeletal muscle mass was significantly correlated with the branched-chain amino acids to tyrosine ratio (r = -0.254, p = 0.005) and body cell mass (r = 0.636, p < 0.001). The overall survival rate in patients with low skeletal muscle mass was significantly lower than in patients with normal/high skeletal muscle mass (p < 0.001). Perioperative nutritional therapy significantly increased overall survival in patients with low skeletal muscle mass (p = 0.009). Multivariate analysis showed that low skeletal muscle mass was an independent risk factor for death after transplantation. In conclusion, sarcopenia was closely involved with posttransplant mortality in patients undergoing LDLT. Perioperative nutritional therapy significantly improved overall survival in patients with sarcopenia.

Pediatric liver transplantation using reduced and hyper-reduced left lateral segment grafts: a 10-year single-center experience

Few studies have examined the long-term outcomes and prognostic factors associated with pediatric living living-donor liver transplantation (LDLT) using reduced and hyper-reduced left lateral segment grafts. We conducted a retrospective, single-center assessment of the outcomes of this procedure, as well as clinical factors that influenced graft and patient survival. Between September 2000 and December 2009, 49 patients (median age: 7 months, weight: 5.45 kg) underwent LDLT using reduced (partial left lateral segment; n = 5, monosegment; n = 26), or hyper-reduced (reduced monosegment grafts; n = 18) left lateral segment grafts. In all cases, the estimated graft-to-recipient body weight ratio of the left lateral segment was more than 4%, as assessed by preoperative computed tomography volumetry, and therefore further reduction was required. A hepatic artery thrombosis occurred in two patients (4.1%). Portal venous complications occurred in eight patients (16.3%). The overall patient survival rate at 1, 3 and 10 years after LDLT were 83.7%, 81.4% and 78.9%, respectively. Multivariate analysis revealed that recipient age of less than 2 months and warm ischemic time of more than 40 min affected patient survival. Pediatric LDLT using reduced and hyper-reduced left lateral segment grafts appears to be a feasible option with acceptable graft survival and vascular complication rates.

Effect of maintenance therapy with low-dose peginterferon for recurrent hepatitis C after living donor liver transplantation

Approximately 30% of patients who have recurrent hepatitis C after liver transplantation achieve sustained virological response (SVR) by taking a combination therapy of pegylated interferon and ribavirin. For the remaining non-SVR patients, an effective management treatment has not yet been established. In this study, efficacy of long-term peginterferon maintenance therapy for non-SVR patients was evaluated. Forty patients who had previously received the combination therapy for hepatitis C after living donor liver transplantation were classified into one of the following three groups: the SVR group (n = 11); the non-SVR-IFN group (n =17), which received low-dose peginterferon maintenance therapy for non-SVR patients; and the non-SVR-Withdrawal group (n = 12), which discontinued the interferon treatment. We then compared histological changes among these three groups after 2 or more years follow-up. Activity grade of liver histology improved or remained stable in patients in the SVR and non-SVR-IFN groups, but deteriorated in half of the patients in the non-SVR-Withdrawal group. Fibrosis improved or remained stable in 10 of 11 SVR patients and in 13 of 17 non-SVR-IFN patients, but deteriorated in all non-SVR-Withdrawal patients. Mean changes in fibrosis stage between pretreatment and final liver biopsy were -0.18, +0.06 and +2.2 in the SVR, non-SVR-IFN and non-SVR-Withdrawal groups, respectively. Fibrosis stage deteriorated to F3 or F4 significantly more rapidly in the non-SVR-Withdrawal group than in the other two groups. In conclusion, continuing long-term maintenance therapy with peginterferon prevented histological progression of hepatitis C in patients who had undergone living donor liver transplantation.

Enhanced inhibitory effects of TBT chloride on the development of F1 rats

Neurotoxicity is one of the major effects of tributyltin (TBT). The effects on the next generation of F(1) rats exposed to TBT via the placenta and their dams' milk may be stronger than those on adults. Pregnant Wister rats were exposed to TBT at 0 and 125 ppm in their food. Half of the female F(1) rats in both groups were exposed to TBT at 125 ppm in their food from 9 to 15 weeks of age. Female F(1) rats were divided into the following groups: the control-control (CC) group, with no exposure; the TBT-control (TC) group, exposed to TBT via the placenta and their dams' milk; the control-TBT (CT) group, exposed to TBT via their food from 9 to 15 weeks of age; and the TBT-TBT (TT) group, exposed to TBT via the placenta, their dams' milk, and their food (n = 10/group). After administration, an open-field test and prepulse inhibition (PPI) test were performed at 15 weeks of age. The mean body weights of the TC and TT groups were significantly lower than that of the CC group from 9 to 15 weeks of age. The mean relative thymus weight of the TC and TT groups was significantly lower than that of the CC group. In the open-field test, a marked decrease in the total locomotion distance was observed in the TT group. The mean values in the TT and TC groups were significantly lower than that in the CC group. For the locomotion distance between 15 and 20 min, the mean values in the CT, TC, and TT groups were significantly lower than that in the CC group. The mean locomotor distance between 25 and 30 min in the TT group was significantly lower than that in the CC and TC groups. The mean values of instances of wall rearing in the TC, CT, and TT groups were significantly lower than that in the CC group. The mean value of face washing or body washing in the TT group was significantly lower than that in the CT group. There were no significant differences in indexes of the PPI test. Exposure to TBT via the placenta and their dams' milk inhibited the development of F(1) rats, which continued after weaning. Inhibition of the rats' activity induced by exposure to TBT via the placenta and their dams' milk and/or via their food was suggested. The effects were most evident in the TT group.

Coupled regulation of interleukin-12 receptor beta-1 of CD8+ central memory and CCR7-negative memory T cells in an early alloimmunity in liver transplant recipients

This study investigated how CD8(+) T cell subsets respond to allo- and infectious immunity after living donor liver transplantation (LDLT). Early alloimmunity: 56 recipients were classified into three types according to the post-transplant course; type I demonstrated uneventful post-transplant course, type II developed severe sepsis leading to multiple organ dysfunction syndrome or retransplantation and type III with acute rejection. In 23 type I recipients, the interleukin (IL)-12 receptor beta-1 (R beta 1)(+) cells of central memory T cells (Il-12R beta 1(+) T(CM)) were increased above the pretransplant level. In 16 type II recipients, IL-12R beta 1(+) T(CM) was decreased markedly below the pretransplant level on postoperative day (POD) 5. In 17 type III recipients, IL-12R beta 1(+) T(CM) was decreased for a more prolonged period until POD 10. Along with down-regulation of IL-12R beta 1(+) T(CM), the IL-12R beta 1(+) cells of CCR7-negative subsets (CNS) as well as perforin, interferon (IFN)-gamma and tumour necrosis factor (TNF)-alpha decreased gradually, resulting in the down-regulation of effectors and cytotoxicity. The down-regulation of IL-12R beta 1(+) T(CM) was suggested to be due to the recruitment of alloantigen-primed T cells into the graft, and then their entry into the secondary lymphoid organ, resulting in graft destruction. Infectious immunity: immunocompetent memory T cells with the capacity to enhance effectors and cytotoxicity were generated in response to post-transplant infection along with both up-regulation of the IL-12R beta 1(+) T(CM) and an increase in the CNS showing the highest level of IL-12R beta 1(+) cells. In conclusion, this work demonstrated that the IL-12R beta 1(+) cells of T(CM) and CNS are regulated in a tightly coupled manner and that expression levels of IL-12R beta 1(+) T(CM) play a crucial role in controlling allo- and infectious immunity.

Significance of des-gamma-carboxy prothrombin in selection criteria for living donor liver transplantation for hepatocellular carcinoma

Des-gamma-carboxy prothrombin (DCP) levels reportedly correlate with histological features of hepatocellular carcinoma (HCC). We examined serum DCP as a predictor of HCC recurrence in 144 patients who underwent living donor liver transplantation. Receiver operating characteristics (ROC) analysis revealed superiority of DCP and AFP over preoperative tumor size or number for predicting recurrence. Multivariate analysis revealed tumor size >5 cm, > or =11 nodules, and DCP >400 mAU/mL as significant independent risk factors for recurrence. Incidence of microvascular invasion (62% vs. 27%, p = 0.0003) and poor differentiation (38% vs. 16%, p = 0.0087) were significantly higher for patients with DCP >400 mAU/mL than for patients with DCP < or =400 mAU/mL. In ROC analysis for patients with < or =10 nodules all < or =5 cm to predict recurrence, area under the curve was much higher for DCP than for AFP (0.84 vs. 0.69). Kyoto criteria were thus defined as < or =10 nodules all < or =5 cm, and DCP < or =400 mAU/mL. The 5-year recurrence rate for 28 patients beyond-Milan but within-Kyoto criteria was as excellent as that for 78 patients within-Milan criteria (3% vs. 7%). The preoperative DCP level offers additional information regarding histological features, and thus can greatly improve patient selection criteria when used with tumor bulk information.

Colon stenosis caused by old portal vein thrombosis

A 58-year-old female with a history of portal vein thrombosis was referred to our hospital with abdominal pain and distention. Colon fiber and enema of the colon showed stenosis at the transverse colon and the ascending colon, with edematous mucosa. Laparotomy revealed no abnormal findings other than chronic ischemia of the colon. To our knowledge, this is the first reported case of colon stenosis caused by portal vein thrombosis.

A huge intrahepatic portal vein aneurysm

Portal vein aneurysm is an unusual vascular abnormality. We report a rare case of a huge intrahepatic portal vein aneurysm at the umbilical portion with hepatic encephalopathy. Abdominal contrast-enhanced dynamic computed tomography and angiography clearly showed a well-circumscribed, 50 x 40-mm portal vein aneurysm at the umbilical portion with portohepatic venous shunt. To our knowledge, this is the largest intrahepatic portal vein aneurysm ever reported.

Large cholesterol polyp of the gallbladder mimicking gallbladder carcinoma

Gallbladder tumors larger than 10 mm in diameter have a high incidence of malignancy. We report an extremely rare case of a large cholesterol polyp of the gallbladder mimicking gallbladder carcinoma. Ultrasonography and computed tomography showed a larger papillary mass in the fundus of the gallbladder with a maximum diameter of about 30 mm, the largest gallbladder polyp ever reported to our knowledge.

Novel complement C1 inhibitor BSF468248 does not improve brain damage after cortical vein occlusion

BSF468248 is a novel potent complement C1 inhibitor. To determine whether BSF468248 is effective against focal cerebral ischemia, we evaluated the change of cerebral blood flow (CBF) and infarction volume using a photochemically-induced cortical vein occlusion model in rats in blind studies. In 22 Wistar rats, two adjacent cortical veins were occluded by photochemical thrombosis and fiberoptic illumination under controlled anesthesia and ventilation. Just after the occlusion, BSF468248 or physiological saline was administrated. In the low-dose study, a treatment group (n = 7) was administered BSF468248 1 mg/kg bolus and 1 mg/kg continuously for 30 min. The same volume of saline was given to a vehicle group (n = 5). In the high-dose study, a treatment group (n = 5) was administrated BSF468248 1 mg/kg bolus and 12 mg/kg continuously for 180 min. The same volume of saline was given to a vehicle group (n = 5). During the experiment, regional cerebral blood flow (rCBF) was measured in both the low-dose study (120 min) and the high-dose study (180 min). Seven days after the experiment, the animals were killed in order to evaluate the infarct volume. The rCBF at the end of the experiment showed a similar decrease in both the low-dose study (at 120 min: treatment group: 66.5 +/- 10.2%; vehicle group: 69.3 +/- 10.2%) and the high-dose study (at 180 min: treatment group: 62.1 +/- 7.5%; vehicle group: 65.1 +/- 12.3%), with no significant differences (t-test). The infarct volume also showed no significant difference in either group of the low-dose study (treatment group: 3.46 +/- 0.84 mm3; vehicle group: 3.56 +/- 1.40 mm3) or the high-dose study (treatment group: 2.27 +/- 0.43 mm3; vehicle group: 1.76 +/- 0.31 mm3). Our study found that BSF468248 is not effective in improving the rCBF and the infarct volume following focal cerebral ischemia.

Characteristics of recurrent hepatocellular carcinoma in Japan and our surgical experience

A nationwide survey conducted by the Liver Cancer Study Group of Japan showed that approximately 85%-90% of recurrences of hepatocellular carcinoma (HCC) were in the remnant liver, and that the location of the intrahepatic recurrence was widely distributed throughout the entire liver, with 30%-40% of the recurrences on the side opposite the primary tumor, beyond Cantlie's line. In our experience, about 70% of the recurrences were seen within 2 years after surgery, and the survival rate tended to be lower as the period from the primary surgery to the recurrence was shorter. To achieve longer survival in patients with HCC, one of the most important issues is, therefore, how to prevent and control intrahepatic recurrence after surgery. Although, according to the nationwide survey, repeat hepatectomy has been performed in only 1.6% of all patients with intrahepatic recurrence, we have experienced 28 patients with repeat hepatic resection. The 1-, 3-, and 5-year survival rates from the time of re-resection were 93%, 59%, and 47%, respectively, and survival rates from the time of the initial surgery were 85% at 3 years, 62% at 5 years, and 53% at 8 years. In particular, in patients with a second primary cancer from multicentric carcinogenesis, the 5-year survival rate after the re-resection was approximately 80%. These results suggested that repeat hepatectomy should be recommended for selected patients.

Inhibitory effect of Y-27632, a ROCK inhibitor, on progression of rat liver fibrosis in association with inactivation of hepatic stellate cells

BACKGROUND/AIMS

Activation of hepatic stellate cells (HSCs) is a final common pathway of liver fibrosis. Recently, it has been demonstrated that the small GTPase Rho is involved in HSCs activation, and that Y-27632, an inhibitor of Rho-kinase which is an effector that acts downstream of Rho, inhibits Rho-associated effects. The objective of the current study was to investigate the inhibitory effects of Y-27632 on the activation of HSCs and the progression of liver fibrosis.

METHODS

Y-27632 (1, 10, 100 microM) was added to HSCs isolated from normal rat liver.

RESULTS

HSCs maintained the 'star-like' configuration of the quiescent stage in the presence of Y-27632, as well as inhibition of the expression of Na+/Ca2+ exchanger mRNA which was reported to be an indicator of HSCs activation. In addition, when Y-27632 (30 mg/kg body weight) was administered to rats with carbon tetrachloride-induced liver fibrosis, collagen deposition was inhibited, the hepatic hydroxyproline content was decreased, and the serum hyaluronic acid level was reduced. Moreover, Y-27632 reduced the number of smooth muscle alpha-actin-positive cells and transforming growth factor-beta1-positive cells, and inhibited the expression of Na/Ca2+ exchanger mRNA.

CONCLUSIONS

These findings indicate that Y-27632 may be useful for the clinical management of liver fibrosis.

Radiosurgery-induced brain tumor. Case report

The authors describe a case of glioblastoma multiforme (GBM) associated with previous gamma knife radiosurgery for a cerebral arteriovenous malformation (AVM). A 14-year-old boy had undergone radiosurgery for an AVM, which was performed using a 201-source 60Co gamma knife system at another institution. The maximum and margin radiation doses used in the procedure were 40 and 20 Gy, respectively. One year after radiosurgery, the patient noticed onset of mild left hemiparesis due to radiation necrosis. Six and one-half years after radiosurgery, at the age of 20 years, the patient experienced an attack of generalized tonic-clonic seizure. Magnetic resonance (MR) imaging revealed the existence of a brain tumor in the right parietal lobe. The patient underwent an operation and the histological diagnosis of the lesion was GBM. Ten months following the operation, that is, 99 months postradiosurgery, this patient died. To the best of the authors' knowledge, this is the first reported case of a neoplasm induced by radiosurgery for an AVM and the second case in which it occurred following radiosurgery for intracranial disease.

Intermittent isometric exposure prevents brain retraction injury under venous circulatory impairment

It is recognized that surgical obliteration of the cerebral veins by additional brain compression using retractors is dangerous. However, there is a lack of satisfactory management of this problem. We investigated whether intermittent brain compression can reduce brain injury from cerebral venous circulation disturbances (CVCDs). In Wistar rats (n = 25), a solitary cortical vein was occluded photochemically. The brain surface was compressed by a spring balance and constant compression at 30 mmHg was carried out for 60 min. Intermittent procedure compression protocols included four 15 min compressions at 5 min intervals, intermittent isometric exposure (IM), and intermittent isotonic exposure (IT). Local cerebral blood flow (ICBF) in the compressed area was measured together by laser-Doppler (LD) with the degree of brain compression. After 24 h, the brains were examined histologically. The animals were divided into the following five groups (each n = 5): 1, a sham operated control; 2, cortical vein occlusion (VO); 3, VO + continuous brain compression (CC); 4, VO + IM; and 5, VO + IT. The ICBF decreased significantly during the compression; however, recovery after the series of compressions was observed only in the VO + IM group, not in the VO + CC and the VO + IT groups (p < 0.05). The depth of the brain surface increased stepwise in the VO + IT group compared with the VO + IM group (p < 0.01). The resulting tissue damage was significantly larger in the VO + CC and VO + IT groups than in the vein occlusion group (p < 0.05), but not in the VO + IM group. The results of the present study suggest that intermittent isometric exposure under CVCDs could decrease brain retraction injury during neurosurgical operations and be more beneficial than continuous compression, providing that the compression pressure declines as the process advances.