Neoadjuvant Down-Sizing of Hilar Cholangiocarcinoma with Photodynamic Therapy--Long-Term Outcome of a Phase II Pilot Study.

Hilar cholangiocarcinoma (CC) is non-resectable in the majority of patients often due to intrahepatic extension along bile duct branches/segments, and even after complete resection (R0) recurrence can be as high as 70%. Photodynamic therapy (PDT) is an established palliative local tumor ablative treatment for non-resectable hilar CC. We report the long-term outcome of curative resection (R0) performed after neoadjuvant PDT for downsizing of tumor margins in seven patients (median age 59 years) with initially non-resectable hilar CC. Photofrin(®) was injected intravenously 24-48 h before laser light irradiation of the tumor stenoses and the adjacent bile duct segments. Major resective surgery was done with curative intention six weeks after PDT. All seven patients had been curatively (R0) resected and there were no undue early or late complications for the neoadjuvant PDT and surgery. Six of seven patients died from tumor recurrence at a median of 3.2 years after resection, the five-year survival rate was 43%. These results are comparable with published data for patients resected R0 without pre-treatment, indicating that neoadjuvant PDT is feasible and could improve overall survival of patients considered non-curatively resectable because of initial tumor extension in bile duct branches/segments--however, this concept needs to be validated in a larger trial.

Long-term outcome of conversion to sirolimus monotherapy after liver transplant.

OBJECTIVES: This study sought to assess the long-term efficacy and safety of conversion from a calcineurin inhibitor-based immunosuppressive regimen to sirolimus monotherapy in liver transplant recipients with renal dysfunction. MATERIALS AND METHODS: Twenty-five liver transplant recipients with calcineurin inhibitor-based immunosuppression were included in this single-center, prospective study. Indications were renal dysfunction, avoidance of tumor recurrence, combination renal dysfunction and avoidance of tumor recurrence, and calcineurin inhibitor-related adverse effects. RESULTS: Mean interval between liver transplant and initiation of sirolimus monotherapy was 51.7 months. The mean follow-up was 75.6 months. The mean ± SD sirolimus whole-blood trough level was 9.0 ± 2.8 ng/mL after 6 months and 6.0 ± 1.8 ng/mL after 18 months. No rejection episodes occurred. There was an improvement of the mean creatinine level: 156.1 ± 54.9 µmol/L before conversion versus 129.1 ± 34.7 µmol/L approximately 3 years after conversion (P < .05). The glomerular filtration rate, measured by technetium Tc-99m-diethylenetriamine penta-acetic aerosol scintigraphy, improved from 27.4 ± 6.8 mL/min/1.73 m(2) before conversion to 43.3 ± 6.3 mL/min/1.73 m(2) at final follow-up. Proteinuria increased after conversion to sirolimus after 6 months (P < .05) and at last follow-up. The systolic blood pressure decreased from 151.5 ± 20.2 to 132.1 ± 19.4 mm Hg, and the diastolic from 89.7 ± 11.2 to 82.1 ± 9.1 mm Hg at last follow-up. Serum cholesterol and serum triglyceride levels were nearly unchanged. However, 50% of the patients were treated with lipid-lowering agents. Four patients had sirolimus-induced adverse effects (thrombocytopenia, gingival hyperplasia, oral ulceration). CONCLUSIONS: Conversion from calcineurin inhibitors to sirolimus monotherapy after liver transplant results in stabilization of renal function in 75% to 85% of cases and of blood pressure, without increased risk of rejection. The spectrum of adverse effects is low.

Predictors of emotional distress in patients with head and neck cancer.

BACKGROUND: Patients with head and neck cancer are known to be more commonly emotionally distressed than patients with other tumors. This study investigates reasons for this difference. METHODS: Patients in this prospective cohort study included those with head and neck cancer (n = 113) and those with other cancers (n = 1690). The Hospital Anxiety and Depression Scale, measuring emotional distress, along with additional questions regarding emotional support wished and provided were administered. RESULTS: Patients with head and neck tumors were 1.5-fold (at the time of admission), 1.2-fold (before discharge), and 2.7-fold (half a year after admission) more frequently distressed than the other patients with cancer. This association was confounded by perceived social support and sociodemographic factors. Patients with head and neck cancer expressed less frequently the wish for and received less support by psycho-oncologists. CONCLUSIONS: Emotional distress is more common in patients with head and neck tumors; this is largely a result of the psychosocial context the patients live in, especially the amount of social support received.

Identifying tumor patients' depression.

PURPOSE: The aim of this study was to compare the precision of two different methods in detecting clinical depression in tumor patients: the use of a screening questionnaire versus the assessment by health care providers (nurses and doctors). METHODS: During their first days of inpatient cancer treatment, tumor patients were interviewed using the Structured Clinical Interview for DSM (SCID). Their physicians and nurses were asked to assess the mental health of the patients and their need for professional psychosocial support. Additionally, every patient completed the Hospital Anxiety and Depression Scale (HADS). RESULTS: Out of 329 patients, 28 were diagnosed with either a major or a minor depression according to the SCID. Physicians assessed 15 of the depressed patients as being depressed (sensitivity, 0.54; specificity, 0.38). Nurses identified 19 (sensitivity, 0.68; specificity, 0.45) and the HADS 27 (sensitivity, 0.96; specificity, 0.50) of the depressed patients. CONCLUSION: The HADS performed well in detecting depressed cancer patients in acute oncological care, whereas physicians and nurses often were unable to recognize depressed patients.

A prospective randomised, open-labeled, trial comparing sirolimus-containing versus mTOR-inhibitor-free immunosuppression in patients undergoing liver transplantation for hepatocellular carcinoma.

BACKGROUND: The potential anti-cancer effects of mammalian target of rapamycin (mTOR) inhibitors are being intensively studied. To date, however, few randomised clinical trials (RCT) have been performed to demonstrate anti-neoplastic effects in the pure oncology setting, and at present, no oncology endpoint-directed RCT has been reported in the high-malignancy risk population of immunosuppressed transplant recipients. Interestingly, since mTOR inhibitors have both immunosuppressive and anti-cancer effects, they have the potential to simultaneously protect against immunologic graft loss and tumour development. Therefore, we designed a prospective RCT to determine if the mTOR inhibitor sirolimus can improve hepatocellular carcinoma (HCC)-free patient survival in liver transplant (LT) recipients with a pre-transplant diagnosis of HCC. METHODS/DESIGN: The study is an open-labelled, randomised, RCT comparing sirolimus-containing versus mTOR-inhibitor-free immunosuppression in patients undergoing LT for HCC. Patients with a histologically confirmed HCC diagnosis are randomised into 2 groups within 4-6 weeks after LT; one arm is maintained on a centre-specific mTOR-inhibitor-free immunosuppressive protocol and the second arm is maintained on a centre-specific mTOR-inhibitor-free immunosuppressive protocol for the first 4-6 weeks, at which time sirolimus is initiated. A 21/2 -year recruitment phase is planned with a 5-year follow-up, testing HCC-free survival as the primary endpoint. Our hypothesis is that sirolimus use in the second arm of the study will improve HCC-free survival. The study is a non-commercial investigator-initiated trial (IIT) sponsored by the University Hospital Regensburg and is endorsed by the European Liver and Intestine Transplant Association; 13 countries within Europe, Canada and Australia are participating. DISCUSSION: If our hypothesis is correct that mTOR inhibition can reduce HCC tumour growth while simultaneously providing immunosuppression to protect the liver allograft from rejection, patients should experience less post-transplant problems with HCC recurrence, and therefore could expect a longer and better quality of life. A positive outcome will likely change the standard of posttransplant immunosuppressive care for LT patients with HCC. TRIAL REGISTER: Trial registered at http://www.clinicaltrials.gov: NCT00355862(EudraCT Number: 2005-005362-36).

A new vagal anchor electrode for real-time monitoring of the recurrent laryngeal nerve.

BACKGROUND: Despite conventional neuromonitoring, the recurrent laryngeal nerve (RLN) is still at risk for damage during thyroid surgery. The feasibility of continuous RLN monitoring by vagal nerve (VN) stimulation with a new anchor electrode should be shown, and electromyographic signal alterations of stressed RLN were analyzed to be alerted to imminent nerve failure whereby the nerve damage becomes reversible. METHODS: VN stimulation was achieved in 23 pigs. Sensed signals were analyzed and stored as real-time audio/video feedback EMG system. RLN was stressed by mechanical and thermal injury; signal alterations were evaluated. RESULTS: VNs were successfully real-time stimulated by using the anchor electrode. No complications or side effects during stimulation were detected. RLN injury led to an alteration of signal amplitude and latency period but signal restitution after injury. CONCLUSIONS: Real-time monitoring of the RLN is technically feasible to perceive imminent nerve failure. The anchor electrode was safely and easy to handle. Its implementation is being tested in an ongoing clinical trial.

Indocyanine green R15 ratio depends directly on liver perfusion flow rate.

BACKGROUND: Indocyanine green (ICG) is a synthetic dye that is widely used to evaluate liver function in critically ill patients, before liver resection or after liver transplantation. Controversy still exists about the impact exerted on the ICG ratio after 15 min (ICG R15) by differences in liver perfusion rates, hyperdynamic states, or patient cardiac output. We studied the role of different liver perfusion rates on the ICG R15 ratio in a normothermic extracorporeal liver perfusion system under standardized conditions. METHODS: Livers from landrace pigs (40-50 kg) were perfused with fresh porcine blood. Normal and high perfusion rates were defined as 1 ml and 2 ml/g liver/min, respectively. Perfusate pressure of the hepatic artery and portal vein were within the physiological range in both groups. According to manufacturer's instructions, 0.5 mg of ICG per kg was applied and the ICG R15 was calculated. Calculations were based on fifteen experiments in five liver perfusions. Bile production, liver function and histology were analyzed. RESULTS: All perfusions were characterized by physiological bile production, lack of hepatocellular damage and normal histology. ICG R15 ratio in group I, perfused with 1 ml/g liver, was 18.9 +/- 6%. In group II, perfused with 2 ml/g liver, the ICG R15 ratio was 7.2 +/- 3%. The difference between groups 1 and 2 was statistically significant (p < 0.05). CONCLUSION: ICG R15 is reliable within one group at defined perfusion rates. Doubled perfusion rates contribute to higher ICG clearance. For clinical application we would like to suggest considering cardiac output of the patient for interpretation of ICG ratios.

Impact of daclizumab, low-dose cyclosporine, mycophenolate mofetil and steroids on renal function after kidney transplantation.

BACKGROUND: Early and long-term use of cyclosporine A (CsA) leads to increased risks of renal toxicity. We hypothesized that administration of daclizumab in combination with mycophenolate mofetil (MMF) allows a relevant reduction in the dose of CsA. METHODS: We carried out a 3-year, prospective, randomized, controlled clinical multi-centre trial in 156 patients. The patients were randomized to standard treatment (CsA, MMF, steroids) or to high-dose daclizumab (first dose: 2 mg/kg), in combination with low-dose CsA, MMF and steroids. We maintained the mean CsA levels of daclizumab patients at 57% of standard patients (132 versus 216 ng/ml) on Day 7 post-transplant, and 84% by 6 months. RESULTS: Primary outcome, creatinine clearance (with imputation of informative dropouts) at 12 months, was significantly better in daclizumab-treated (34 +/- 17) than standard patients (29 +/- 17; P = 0.028, two sided). Only 5 cases of BPAR were recorded in the daclizumab compared to 22 in the standard group (P = 0.0016). Daclizumab patients had 91% event-free survival after 1 year compared to 66% in standard patients (P = 0.00017). CONCLUSION: We demonstrate here that high-dose daclizumab in combination with lower CsA levels in adult renal transplant recipients is as or more effective than standard regimen (CsA, MMF, steroids) and may result in better outcomes at 12 months post-transplant with no increase in adverse reactions.

Serum peptidome profiling revealed platelet factor 4 as a potential discriminating Peptide associated with pancreatic cancer.

PURPOSE: Mass spectrometry-based serum peptidome profiling is a promising tool to identify novel disease-associated biomarkers, but is limited by preanalytic factors and the intricacies of complex data processing. Therefore, we investigated whether standardized sample protocols and new bioinformatic tools combined with external data validation improve the validity of peptidome profiling for the discovery of pancreatic cancer-associated serum markers. EXPERIMENTAL DESIGN: For the discovery study, two sets of sera from patients with pancreatic cancer (n = 40) and healthy controls (n = 40) were obtained from two different clinical centers. For external data validation, we collected an independent set of samples from patients (n = 20) and healthy controls (n = 20). Magnetic beads with different surface functionalities were used for peptidome fractionation followed by matrix-assisted laser desorption/ionization time-of-flight (MALDI-TOF) mass spectrometry (MS). Data evaluation was carried out by comparing two different bioinformatic strategies. Following proteome database search, the matching candidate peptide was verified by MALDI-TOF MS after specific antibody-based immunoaffinity chromatography and independently confirmed by an ELISA assay. RESULTS: Two significant peaks (m/z 3884; 5959) achieved a sensitivity of 86.3% and a specificity of 97.6% for the discrimination of patients and healthy controls in the external validation set. Adding peak m/z 3884 to conventional clinical tumor markers (CA 19-9 and CEA) improved sensitivity and specificity, as shown by receiver operator characteristics curve analysis (AUROC(combined) = 1.00). Mass spectrometry-based m/z 3884 peak identification and following immunologic quantitation revealed platelet factor 4 as the corresponding peptide. CONCLUSIONS: MALDI-TOF MS-based serum peptidome profiling allowed the discovery and validation of platelet factor 4 as a new discriminating marker in pancreatic cancer.

A new anchor electrode design for continuous neuromonitoring of the recurrent laryngeal nerve by vagal nerve stimulations.

PURPOSE: Intraoperative neuromonitoring has the limitation that the recurrent laryngeal nerve (RLN) is still at risk for damage between two stimulations with a handheld bipolar stimulation electrode. The purpose of this study was to establish the vagal anchor electrode for real-time monitoring of the RLN in surgical routine and to be alerted to imminent nerve failure by electromyography (EMG) signal analysis whereby the nerve damage becomes reversible. PATIENTS AND METHODS: This fully implantable electrode has been used in addition to a conventional handheld bipolar stimulation electrode during thyroid surgery on 45 consecutive patients (78 nerves at risk) stratified to low- and high-risk groups. The signal analysis was performed as real-time audio/video feedback by the use of a new multichannel EMG system. RESULTS: No complications were attributable to the use of the anchor electrode. The mean delay to place the anchor electrode was 1.45 min, whereas the mean stimulation time of the vagus nerve was 38 min. Stable and repeatable signals were evocable in all cases with one exception. No permanent RLN paralyses occurred in this study. CONCLUSIONS: The vagal anchor electrode is safe and easy to use. It allows continuous neuromonitoring without any threats. The new technique will provide more security, especially during preparation steps on the RLN that are difficult for the surgeon.

Percutaneous intragastric catheter (PIC) for administration of an unpalatable substance to large animals.

We studied an easy and reliable technique for administration of an unpalatable substance to large animals. There were three groups of pigs: group I (n = 6) received 1 g ethanol/kg body weight per day orally with water for 24 days, group II (n = 6) received 2 g ethanol/kg orally with water for 24 days and 4 g ethanol/kg via percutaneous intragastric catheter (PIC) for the next 24 days, group III (n = 6) received 6 g ethanol/kg via PIC for 72 days. The catheter was placed after insufflation of the stomach using an orogastric tube. PIC was successfully placed in each pig. No complications occurred during placement. The total amount of the administrated dose was assimilated each time. PIC is a safe, effective, well tolerated, and precise method of administering ethanol that is inexpensive and easy to perform. Ethanol administration via PIC is a convenient and effective mean of exposing animals to high levels of alcohol on a long-term basis.

Vaspin serum concentrations in patients with carotid stenosis.

Obesity is associated with accelerated atherosclerosis. Adipokines may directly influence vessel wall homeostasis by influencing the function of endothelial cells, arterial smooth muscle cells, and modulating inflammation. Recently, visceral adipose tissue-derived serpin (vaspin) was identified as a novel adipokine related to obesity and its metabolic consequences. However, the regulation of vaspin serum concentrations in human atherosclerosis is unknown. We therefore assessed vaspin serum concentrations in 107 consecutive patients with carotid stenosis undergoing carotid endarterectomy (CEA) in relation to severity of atherosclerosis, measures of obesity and circulating markers of obesity and atherosclerosis. Vaspin serum concentrations were significantly lower in patients with carotid stenosis who experienced an ischemic event within 3 months before surgery compared to asymptomatic patients. However, circulating vaspin was not associated with measures of atherosclerosis severity as maximum percentage stenosis. Vaspin serum concentrations were indistinguishable before and after CEA. We found a significant correlation between vaspin and leptin serum concentrations supporting previous results that vaspin closely reflects body fat mass. In conclusion, our data show that low vaspin serum concentrations correlate with recently experienced ischemic events in patients with carotid stenosis despite the lack of an association between circulating vaspin and parameters of atherosclerosis severity.

Prognostic value of eicosanoid pathways in extrahepatic cholangiocarcinoma.

BACKGROUND: Chronic inflammation of the bile duct is linked to an increased risk for the development of cholangiocarcinoma. Arachidonic acid and linoleic acid oxidation through cyclooxygenase and lipoxygenase--two major pro-inflammatory pathways--have rarely been investigated in extrahepatic cholangiocarcinoma. MATERIALS AND METHODS: Paraffin-embedded specimens from 51 resected adenocarcinomas of the extrahepatic bile duct were immunostained for cyclooxygenase 2 (COX-2) and 5-lipoxygenase (5-LOX) to evaluate their intracellular distribution and prognostic value. RESULTS: Cholangiocarcinoma had significantly higher levels of 5-LOX and COX-2 expression compared with normal tissue (p = 0.015). High expression of nucleus-located 5-LOX was significantly associated with intensive staining for COX-2, (p = 0.023). Median disease-free survival (DFS) in patients with low expression of 5-LOX was significantly better than in patients with high expression of 5-LOX (log rank p = 0.046). DFS in patients with low COX-2 expression was also significantly better than DFS in patients with high COX-2 expression (log rank p = 0.0187). CONCLUSION: The present study demonstrates that 5-LOX and COX-2 protein expression was increased in cholangiocarcinoma suggesting that these two enzymes might be of prognostic value and offer a potential additional adjuvant therapeutic approach to this disease.

A single-center experience with liver transplantation for Wilson's disease.

Wilson's disease is an inherited disorder of copper metabolism, presenting with prominent hepatic and neurologic manifestations. There is an established place for liver transplantation in the presence of liver disease, while the indication for neurologic manifestations is debated. Between 1993 and 2005, 11 patients were liver transplanted for Wilson's disease at our institution. We retrospectively reviewed the medical records of the patients. The pathology of the explanted livers was analyzed. The patients were divided into three groups based on the evolution of the disease. Postoperative data gathered included patient and graft outcome, complications, neurologic status, and copper metabolism. Six males and five females were transplanted at a mean age of 29.7 yr (range 15-48 yr). Three patients had a fulminant presentation, two patients had decompensation of established disease, and six patients had chronic disease. Neurologic features were prominent in five patients. The pathologic analysis of the explanted graft showed cirrhosis in all patients. The five patients with fulminant and acute on chronic presentations also showed necrosis in the explant. The mean postoperative follow-up was 56.8 months (range 10-129 months). Two patients were re-transplanted. One patient died because of severe sepsis. Two patients with severe neurologic dysfunction showed significant remission of symptoms. Liver transplantation is a safe and effective treatment for both acute and chronic presentations of Wilson's disease. Acute presentation correlates with the presence of necrosis in the explanted liver. In our series, there was a relevant improvement of the neurologic features after transplantation.

Unchanged high mortality rates from acute occlusive intestinal ischemia: six year review.

OBJECTIVE: Acute intestinal ischemia (AII) is an uncommon surgical emergency that has been increasing in incidence and remains a highly lethal condition with a difficult diagnosis. We undertook this study to evaluate our experience in treating this condition with a view to expand the cumulative information in the literature. MATERIALS AND METHODS: Between January 2000 and December 2006, 60 patients with AII caused by thrombotic vascular event underwent surgery at our surgical center. The patients' medical records including data covering demographic features, comorbid medical conditions, medical risk factors, clinical symptoms, history and physical examination findings, and biochemical and radiologic examinations were reviewed. Operative records, the American Society of Anesthesiology physical status classification (ASA-PS), postoperative complications, duration of hospital stay, and final outcome were also considered. RESULTS: Of the 60 patients with primary thrombotic vascular event, 20 patients had embolism and 19 patients arterial thrombosis. In 21 patients, mesenteric venous thrombosis was the etiology of AII. The median age was 73 years (range, 43-96). Higher ASA classification, age >70 years, late presentation, and high serum lactate levels were predictors of adverse outcome. The overall death rate was 60% (36/60), which was within the range of that observed in the published series. CONCLUSION: AII remains a highly lethal condition. Mortality rates remain as high as they did decades ago due in part to advanced presentation and advanced age with multiple associated conditions and risk factors, all of which are independent predictors of adverse outcome.

Polycystic liver and kidney disease: post-transplant kidney function in patients receiving pre-emptive kidney transplantation.

The aim of the study is to evaluate the changes in kidney function after pre-emptive kidney transplantation in patients with polycystic liver and kidney disease (PLKD) and to establish whether pre-emptive kidney transplantation is warranted. Between 1998 and 2006, five patients with severe anatomical changes in both native kidneys but only mild alteration of the clearance function received combined liver and kidney transplantation. Preoperatively, Technetium-99m mercaptoacetyltriglycine (Tc99m MAG3) scintigraphy was used to evaluate separately the function of each native kidney. This examination was repeated six months after transplantation, additionally measuring the function of the transplanted kidney. Pretransplant creatinine levels were 77-115 mumol/l and Tc99m MAG3 clearance was 141-163 ml/min/1.73 sqm (74 +/- 8% of minimum-for-age values). Six months after transplant, creatinine values were not significantly different. Minimum-for-age clearance decreased by 12.5 +/- 11.5% in four patients, and increased by 26% in one patient. In four patients, the transplanted and the native kidneys assumed each about one third of total tracer clearance. In one patient, the transplanted kidney assumed 92% of the clearance function. Kidney function decreases despite pre-emptive kidney transplantation. Native kidneys are not functionally excluded and the clearance seems to be divided between native and transplanted organs. Kidney transplantation in nonuremic PLKD patients does not improve the overall kidney function and should be performed only in exceptional cases.

Signet-ring cell carcinoma arising in the gastric stump after duodenopancreatectomy for ductal adenocarcinoma of the pancreas: a case report.

The development of malignancy in the gastric stump following surgery for peptic ulcer disease is well recognized. There are also few reports on carcinomas occurring after surgery for malignant gastric disease. However, carcinoma of the gastric stump after duodenopancreatectomy is extremely rare. We describe what we believe to be an unusual case of signet-ring cell carcinoma of the gastric stump developing at the anastomotic site 5 years after duodenopancreatectomy for ductal adenocarcinoma of the pancreatic head. We performed remnant gastrectomy and Roux-en-Y gastrojejunostomy as a curative resection. This experience clearly underlies that g astric stump carcinoma (GSC) may mimic metastatic disease recurrence leading to diagnostic confusion after surgery for malignancy. Although an increased risk of gastric stump carcinoma after pancreatoduodenectomy for pancreatic cancer has not been established, the possibility of such a complication should be kept in mind when evaluating patients after gastric resection who present with symptoms of metastatic disease recurrence years after the primary operation. Investigations should be independent of the entity of the primary disease or its localization, since GSC may well be amenable to surgical cure as demonstrated in the presented case. Outpatient follow up results of the last four years indicated no recurrence in this case.

Therapeutical concepts and results for Klatskin tumors.

INTRODUCTION: Most hilar cholangiocarcinomas (Klatskin tumors) are diagnosed at an advanced stage. This article aims to review the literature of resection and palliative treatment in patients with hilar cholangiocarcinoma. METHODS: All studies with evidence levels I and II and relevant trials with evidence level III from 1996 to 04/2007 were included. RESULTS: The definition of resectability depends not only on tumor stage but also on operator experience. The best long-term results are achieved by hilar resection combined with extended liver resection. No clear clinical benefit has been demonstrated for neoadjuvant and adjuvant therapies. The role of liver transplantation requires redefinition in view of good long-term survival after neoadjuvant chemoradiation and the possibility of living-donor liver transplantation. Initial studies of a combination of biliary stenting and photodynamic therapy (PDT) for palliation have shown significantly prolonged survival times compared with stenting alone. There is no established standard palliative chemotherapy. DISCUSSION: The prognosis of patients with Klatskin tumors has been significantly improved by extended resection procedures. The combination of stenting and PDT is a useful palliative approach.

Regenerative capacity differs between micro- and macrovesicular hepatic steatosis.

INTRODUCTION: Independent of etiology, the hepatic microvesicular steatosis has a worse prognosis compared with macrovesicular steatosis. Proliferation compensates for apoptosis and reflects regenerative mechanisms following liver injury. It is unknown whether these two types of fatty liver have differences in regenerative capacity and apoptosis, which could have an impact on their prognosis. METHODS: Two groups of pigs were studied for 72 days under a protein-deficient diet. One group received only protein-deficient diet (n=6), the other was treated in addition to the diet with 6g ethanol/kg/day by means of a percutaneous intragastric catheter (n=6). The rate of proliferating and apoptotic hepatocytes was determined, respectively, by proliferation cell nuclear antigen (PCNA) and ISEL/TUNEL staining for apoptosis in liver biopsies with similar steatosis grade in pigs with micro- or macrovesicular fatty liver. RESULTS: The ethanol-treated group developed microvesicular steatosis, the other group developed macrovesicular steatosis. Proliferation index was significantly increased in macrovesicular in comparison with microvesicular steatosis (p<0.05). Apoptosis rate was similar in both groups. CONCLUSIONS: Regeneration, but not apoptosis rate differs between micro- and macrovesicular steatosis. The reduced regenerative capacity in microvesicular steatosis may contribute to the worse prognosis of this subtype of fatty liver disease.