Randomized clinical trial of open hepatectomy with or without intermittent Pringle manoeuvre

BACKGROUND

The intermittent Pringle manoeuvre (IPM) is commonly applied during liver resection. Few randomized trials have addressed its effectiveness in reducing blood loss and the results have been conflicting. The present study investigated the hypothesis that IPM could reduce blood loss during liver resection by 50 per cent.

METHODS

Between May 2008 and April 2011, patients who underwent elective open hepatectomy were randomized into an IPM or no Pringle manoeuvre (NPM) group and stratified according to the presence or absence of cirrhosis. Data on demographics, type of hepatectomy, operative blood loss, duration of operation, mortality, morbidity and postoperative liver function were recorded and analysed. The primary endpoint was operative blood loss.

RESULTS

There were 63 patients in each group. Median (range) operative blood loss was 370 (50-3600) ml in the IPM group versus 335 (40-3160) ml in the NPM group (P = 1·000). There were no differences in blood loss in different phases of the operation, blood loss per area of liver transected or blood transfusion rate, nor in total duration of operation or liver transection time. Postoperative serum alanine aminotransferase levels were higher in the IPM group (P < 0·001). There were more postoperative complications in the IPM group (41 versus 24 per cent; P = 0·036).

CONCLUSION

The IPM did not reduce blood loss, but was associated with raised levels of postoperative liver parenchymal enzymes and more complications.

REGISTRATION NUMBER

NCT00730743 (http://www.clinicaltrials.gov).

The analgesic efficacy of continuous wound instillation with ropivacaine after open hepatic surgery

The analgesic efficacy of continuous local anaesthetic wound instillation after open hepatic surgery was evaluated. Forty-eight patients scheduled for elective liver surgery were assigned to receive either ropivacaine 0.25% or saline infusion at 4 ml.h(-1) for 68 h via two multi-orifice indwelling catheters placed within the musculo-fascial layer before skin closure; plasma ropivacaine concentrations were measured during the infusion. Supplemental analgesia was provided by intravenous patient-controlled analgesia morphine. Patients in the ropivacaine group had decreased mean (SD) total morphine consumption (58 (30) mg vs 86 (44) mg, p = 0.01) and less pain at rest as well as after spirometry at 4, 12, 24, 48 and 72 h postoperatively (p < 0.01). Forced vital capacity was reduced postoperatively in both groups, but the reduction was greater in the saline group at 12 and 24 h (p = 0.03). The mean plasma concentration of ropivacaine increased to 2.05 (0.78) μg.ml(-1) at the point when the infusion was terminated.

Predictors of treatment outcomes in early stage hepatocellular carcinoma (HCC) detected in a surveillance program

4584

Background: Surveillance for HCC in hepatitis B virus (HBV) carriers aims to improve survival by detection of early resectable tumor. In 2005, our group reported low surgical resection rates despite detection of small sized tumors in a prospective surveillance cohort of 1018 HBV carriers (Mok TS et al. J Clin Oncol 05). In current study, we aim to identify predictive factors for treatment outcomes in HCC detected from our surveillance program. Methods: The prospective cohort was recruited at the Prince of Wales Hospital between Oct 1997 and Nov 2000. We updated the database in Dec 2008 and performed univariate and multivariate analysis on clinical (age, sex, cirrhosis, ascites, anti-viral therapy, bilirubin, ALT, albumin, INR), tumorous (size, number, resection) and virologic factors (HBV DNA, Genotype) for prediction of outcome in HCC patients (pts). Results: In the prospective cohort, total 923 HBV carriers were updated (95 lost to follow-up). After median follow-up of 9.95 years, we confirmed diagnosis of 105 HCC. Median age = 51 (range: 40–69); M:F = 82:23; Child's A and B cirrhosis = 38:67. Fifty seven pts (54.3%) had solitary tumor but only 34 (32.4%) are amenable to resection. Absence of cirrhosis (p=0.0072) and normal albumin level (p=0.0379) are predictors of surgical resection while tumor size and number are not. The median survival of all HCC pts was 2.26 years. Anti-viral therapy during the surveillance period is a strong predictor of survival (3.74 vs. 1.63 years; p=0.0115). In multivariate analysis, both anti- viral therapy (HR=0.35; 95%CI: 0.19–0.73; p=0.0041) and normal bilirubin level (HR=0.30; 95% CI: 0.25–0.80; p=0.0069) were predictive of improved survival in pts with HCC. The benefits of anti-viral therapy applied to both surgical and non-surgical candidates (p=0.17). Conclusions: Anti-viral therapy is a potent predictor of survival of HBV related HCC. Liver function is more important than tumor characteristics in determining the outcome of HCC detected in the surveillance program.

No significant financial relationships to disclose.

Correlation of Ki67, topo IIa, MRP1, p53 and p-gp with chemo-responsiveness and survival in patients with hepatocellular carcinoma (HCC)

4139

Background: HCC is a common cause of cancer morbidity and mortality. For patients (pts) who are not candidate of curative surgery, chemotherapy (CT) is one of the main treatments but response has been poor due to drug resistance. In this study, using the pre-CT tumor biopsies of HCC pts who were entered into our recently reported phase III prospective randomized CT study (J Natl Cancer Inst 2005; 97(7): 536–539), we aimed to correlate selected biomarkers with CT responsiveness and survival. Methods: 188 HCC pts were entered into the CT study. They were separately consented for the present correlative study. CT response was based on WHO criteria. For the purpose of this study, pts were categorized into CT-‘responsive’ group (those who obtained clinical benefits and achieved CR, PR or SD) and CT-‘non-responsive’ group (those who developed PD). Immunohistochemical staining for Ki67, topo IIa, MRP1, p53 and p-gp were performed on the pre-CT tumor biopsies; findings of which were analyzed with conventional clinical variables to identify factors that influenced CT response and survival. Results: 149 pts had pre-CT tumor biopsies available and were thus included in the present analysis, 1 pt was not assessable for response; there were 75 pts in the CT-‘responsive’ group (23 PR and 52 SD) and 73 pts in the CT-‘non-responsive’ group. The overall median survival was 7.9 months. Using multivariate analysis, predictors of response to CT were Ki67 positivity (p = 0.0427; OR = 0.475), MRP1 positivity (p = 0.0323; OR = 0.429), age (p = 0.0027; OR = 1.056) and albumin level (p = 0.0130; OR = 1.108). Predictors of survival included Ki67 positivity (p = 0.0097; HR = 1.662), topo IIa positivity (p = 0.0358; HR = 1.566), total bilirubilin level (p = 0.0006; HR = 1.039) and ALT level (p = 0.0092; HR = 1.005). Conclusions: In addition to conventional factors, Ki67 and MRP1 positivity are predictors of response to CT, while Ki67 and topo IIa positivity are predictors of survival. The present study demonstrates that immunohistochemical staining of biomarkers can be instrumental in highlighting genes in the drug-resistant phenomenon of HCC. Acknowledgements: This study has been supported by the Direct Grant of Chinese University of Hong Kong, project no. 2041124.

No significant financial relationships to disclose.

Incidence of deep vein thrombosis after colorectal surgery in a Chinese population

INTRODUCTION

Contemporary studies indicate that the incidence of deep vein thrombosis (DVT) is increasing in the Asian population. The present study aims to evaluate the incidence of postoperative DVT in Chinese patients undergoing surgery for colorectal malignancies.

METHODS

Fifty-one consecutive patients with carcinoma of the rectum or sigmoid colon scheduled for resection were included in the study. None of the study subjects were given any form of DVT prophylaxis. Serial duplex ultrasound of both lower limbs were examined in the preoperative and postoperative periods.

RESULTS

Three patients were excluded from the study because of the presence of DVT noted preoperatively. A total of 20/48 (41.7%) patients developed asymptomatic calf vein thrombosis. One out of 20 patients required anticoagulation because of thrombus propagation. None of the subjects showed signs or symptoms of DVT or pulmonary embolism. A total of 7/20 thrombi resolved completely at 4 weeks after operation. Only old age and smoking were identified as being associated with a higher incidence of DVT. Disseminated disease, type of operation, duration of operation and postoperative complications did not appear to be risk factors for DVT.

CONCLUSION

A high incidence of asymptomatic calf vein thrombosis occurred after colorectal surgery for malignancies in Chinese. The majority did not progress even without anticoagulation.

Induction of Fas and Fas ligand expression on malignant glioma cells by Kupffer cells, a potential pathway of antiliver metastases

Kupffer cells play an important role in controlling the growth and development of liver metastases. However, the pathway of Kupffer cells against tumor metastases is not clear. In the present study, we set up an experimental model to investigate the mechanisms on how Kupffer cells kill tumor cells which metastasize to the liver. Malignant glioma cells were cocultured with Kupffer cells or treated with culture medium collected from lipopolysaccharide (LPS)-activated Kupffer cells. The results showed that the interaction between Kupffer cells and malignant glioma cells significantly stimulated the generation of tumor necrosis factoralpha (TNFalpha). TNFalpha was mainly produced by Kupffer cells, as its level in culture medium obtained from LPS-treated Kupffer cells was not significantly different from that of malignant glioma cells treated with the same medium. Both Kupffer cells and LPS/Kupffer cell-conditioned supernatants induced expression of Fas and Fas ligand on malignant glioma cells. Subsequently a significant proportion of malignant glioma cells became apoptotic, as evidenced by positive staining of annexin V and propidium iodine and an increase in cellular DNA fragmentation. Therefore, this study supports a novel pathway of Kupffer cells against liver metastases, in which tumor cells were apoptotic via the Fas-Fas ligand system induced by TNFalpha released from Kupffer cells.

Immunohistochemical analysis of pro-apoptotic Bid level in chronic hepatitis, hepatocellular carcinoma and liver metastases

Bid, a member of the Bcl-2 family, mediates apoptosis by inducing the release of proapoptotic factors. The expression of Bid in liver diseases has not been investigated. This study evaluated Bid level in various liver diseases including hepatocellular carcinoma (HCC), liver metastases from colorectal cancer, chronic hepatitis and liver cirrhosis. The expression of Bid in tumorous tissues of HCC was lower than that in their corresponding non-tumorous tissues from the same patient. Heavy staining with Bid antibody was found in some localized tumorous liver tissues from patients with poorly differentiated tumors. In patients with chronic hepatitis and liver cirrhosis, there were gradient tumor-development centers, a gradient increase in reaction with Bid antibody from the middle of the center to its edge. The gradient tumor-development center was also found in non-tumorous tissues of HCC, suggesting that occurrence of this center in chronic hepatitis might be an early pathologic sign of HCC development. Bid was also expressed in the epithelial cells in tissues from liver metastases and their expression was often stronger than in the non-tumorous liver tissues. Heavy nuclear staining of Bid was not uncommon in these metastatic cells. The different patterns of staining between primary and secondary liver tumors may reflect a difference in tumor origin and in cell type. Nuclei of metastatic cells, though positive for Bid, still showed a considerable mitotic activity, indicating that they were in active proliferation rather than on a pathway deemed to be apoptotic. In conclusion, this study shows that the Bid level is decreased in HCC except in poorly differentiated HCC in which cells may undergo a process of apoptosis or necrosis. The existence of gradient tumor-development center in chronic hepatitis, liver cirrhosis and non-tumorous tissues from HCC may serve as a pathologic marker of a carcinogenic change of cell phenotypes.

Decreased expression of Bid in human hepatocellular carcinoma is related to hepatitis B virus X protein

As a mitochondrial membrane death ligand, Bid oligomerises Bak to release cytochrome C and its deficiency renders hepatocytes resistant to apoptosis induced by Fas. The Bid level in hepatocellular carcinoma (HCC) is unknown. In this report, we examined the expression of Bid protein and mRNA in HCC cancerous tissues and their corresponding non-cancerous ones. The effect of the hepatitis B x protein (HBx) on the expression of Bid was also evaluated by transfecting hepatoma cells with the HBx gene. The results showed that the expression of Bid was significantly lower in cancerous tissues than that in their corresponding non-cancerous tissues. Immunohistochemical study revealed that Bid molecule was mainly localised in hepato-cytoplasm. Some nuclei were also positive for Bid antigen though to a lesser degree. In vitro experiments demonstrated that the expression of Bid in cells transfected with HBx was significantly lower than that in the cells without HBx transfection. This finding suggests that HBx may play a causative role in the reduction of Bid expression in HCC. This in vitro result is, to some degree, supported by clinical data that all the HCC examined are positive for hepatitis B virus (HBV). We conclude from this data that the expression of Bid in HCC is significantly decreased and the reduction of Bid may result from a mechanism associated with HBx, a major hepatocarcinogenic product from HBV. The imbalance of increased anti-apoptosis and decreased pro-apoptosis seen in HCC is a critical mechanism leading to the uncontrolled growth of tumour cells. Therefore, this study suggests that a deficiency in the expression of Bid may contribute to the development of such an imbalance in HCC.

Hypomethylation of chromosome 1 heterochromatin DNA correlates with q-arm copy gain in human hepatocellular carcinoma

Using comparative genomic hybridization (CGH) analysis, we, and others, have shown that there is a high and consistent incidence of chromosome 1q copy gain in human hepatocellular carcinoma (HCC). Chromosome 1 rearrangements, that involved peri-centromeric breakpoints, have also been frequently reported in karyotypic studies of HCC. Satellite DNA hypomethylation has been postulated as the mechanism underlying the induction of chromosome 1 peri-centromeric instability in many human cancers and in individuals with the rare recessive disorder ICF (immunodeficiency, centromeric heterochromatin instability, facial anomalies). In this study, we have investigated the role of DNA hypomethylation in 1q copy gain in HCC by examining the methylation status of chromosome 1 heterochromatin DNA (band 1q12). Thirty-six histologically confirmed samples of HCC were studied (24 paired tumor and adjacent nontumorous liver tissues, and 12 tumor only). Hypomethylation of satellite 2 (Sat2) DNA in 1q12 was analyzed by Southern blotting using methyl-sensitive enzyme digestion. In parallel, all cases were analyzed by CGH. A strong correlation between hypomethylated Sat2 sequences and 1q copy gain with a 1q12 breakpoint was found (P < 0.001). We postulate that such hypomethylation alters the interaction between the CpG-rich satellite DNA and chromatin proteins, resulting in heterochromatin decondensation, breakage and aberrant 1q formation. Spectral karyotyping further supported the presence of fragile 1q12 in HCC. Of particular interest was the finding of Sat2 DNA hypomethylation in 5 of 24 adjacent nontumorous liver tissues examined. These tissues showed no evidence of malignancy on histological examination nor did they display any CGH abnormalities. Our findings suggest a role for Sat2 demethylation in the early stages of the stepwise progression of liver carcinogenesis.

Circulating Epstein-Barr virus DNA in the serum of patients with gastric carcinoma

PURPOSE

We investigated the detectability of EBV DNA in the serum of gastric carcinoma patients in Hong Kong. Previous data have shown that approximately 10% of gastric carcinomas in Hong Kong are associated with EBV.

EXPERIMENTAL DESIGN

We recruited 51 patients with gastric carcinoma, 30 patients with gastritis, and 197 apparently healthy controls. For gastric carcinoma patients, blood samples were obtained before surgery. After surgery, the resected tumor samples from the cancer cases were subjected to in situ hybridization for small EBV-encoded RNA (EBER). Serum EBV DNA in all cases was measured by real-time quantitative PCR.

RESULTS

Serum EBV DNA was detectable in 5 of 5 (100%) EBER-positive gastric carcinoma cases (median concentration, 1063 copies/ml), in 13 of 14 (93%) EBER-negative gastric carcinoma cases with EBER-positive infiltrating lymphocytes (median concentration, 50 copies/ml), and in 0 of 32 (0%) EBER-negative cases. In the nontumor controls, serum EBV DNA was detectable in 7 of 30 (23%) gastritis cases (median concentration, 0 copies/ml) and in 7 of 197 (3.6%) apparently healthy individuals (median concentration, 0 copy/ml).

CONCLUSIONS

Our data indicate that serum EBV DNA reflects tumoral EBER status and opens up the possibility that circulating EBV DNA may be used as a tumor marker for the EBER-positive gastric carcinomas. The biological and clinical significance of the presence of low levels of circulating EBV DNA in the minority of gastritis patients and healthy individuals remains to be elucidated.

Differential gene expression of hepatocellular carcinoma using cDNA microarray analysis

A cDNA microarray technique, which allows simultaneous analysis of differential expression of mRNA of over 4000 known human genes, was utilized to study the gene expression in 10 pairs of HCC and nontumorous tissues from ethnic Chinese patients in Hong Kong. A total of 211 genes were found to be highly expressed and 147 genes were downregulated in more than 1 out of 10 of the HCC pairs. The results were significant by two-tailed Wilcoxon test (P < or = 0.05 with 95% confidence) on the intensity of each DNA spot of the 10 HCC pairs. Six genes were highly expressed and 10 genes were downregulated in more than 30% of HCC pairs. Results are consistent with other published reports using traditional differential display, subtractive hybridization, or immunohistochemical staining methods. We also detected that beta-actin and glyceraldehyde 3-phosphate dehydrogenase (G3PDH), which have been commonly used as an internal standard control in mRNA expression studies, were highly expressed in HCC when compared with nontumorous tissue. It is concluded that cDNA microarray analysis is an effective method in the detection of differential gene expression in HCC.

Does patient position during liver surgery influence the risk of venous air embolism?

BACKGROUND

It is generally believed that positioning of the patient in a head-down tilt (Trendelenberg position) decreases the likelihood of a venous air embolism during liver resection.

METHODS

The physiological effect of variation in horizontal attitude on central and hepatic venous pressure was measured in 10 patients during liver surgery. Hemodynamic indices were recorded with the operating table in the horizontal, 20 degrees head-up and 20 degrees head-down positions.

RESULTS

There was no demonstrable pressure gradient between the hepatic and central venous levels in any of the positions. The absolute pressures did, however, vary in a predictable way, being highest in the head-down and lowest during head-up tilt. However, on no occasion was a negative intraluminal pressure recorded.

CONCLUSION

The effect on venous pressures caused by the change in patient positioning alone during liver surgery does not affect the risk of venous air embolism.

Necrosis of the nasal ala after improper taping of a nasogastric tube

Inserting a nasogastric tube during various abdominal procedures is a common maneuver to decompress the upper gastrointestinal tract. Improper placement and taping of the nasogastric tube results in excessive pulling on the nasal ala and subsequent pressure necrosis. This complication not only carries serious cosmetic morbidity, it is also preventable if a proper taping technique is employed.

Local renin-angiotensin system in the pancreas: the significance in acute pancreatitis

Acute pancreatitis is a complex disease entity of which the pathogenesis is still not completely known. Research into the initiation and propagation of the diseases would hopefully help to design new treatment strategies for patients, especially those with severe acute pancreatitis. The novel observation of the activation of the local pancreatic renin-angiotensin system in experimental pancreatitis opens up new horizons for research regarding the pathogenesis of acute pancreatitis.

Selection of patients for laparoscopic repair of perforated peptic ulcer

BACKGROUND

Although randomized and non-randomized studies have evaluated the safety of laparoscopic repair for perforated peptic ulcer, no definite guidelines have been published on selection of patients for laparoscopic repair. This cohort study aimed to define patients who may not benefit from laparoscopic techniques.

METHODS

The data from 374 consecutive patients with perforated peptic ulcer treated by simple repair were collected prospectively and analysed.

RESULTS

From January 1992 to December 1998, 219 patients were treated by open suture repair, 109 by laparoscopic sutureless (fibrin glue) repair and 46 by laparoscopic suture repair. The overall leak rate after laparoscopic suture and sutureless repair was 6 and 16 per cent respectively. Leakage was noted to be associated with a significantly higher rate of wound infection, intra-abdominal abscess formation, prolonged ileus (P < 0.001) and longer hospital stay (11 versus 5 days; P < 0.001). Multivariate analysis demonstrated that Acute Physiology and Chronic Health Evaluation (APACHE) II score on admission predicted the likelihood of a leak after laparoscopic fibrin glue repair (P = 0.006).

CONCLUSION

APACHE II score may be a useful index for selecting patients for laparoscopic fibrin glue repair.

Effects of hepatic blood inflow occlusion on liver regeneration following partial hepatectomy in an experimental model of cirrhosis

BACKGROUND

Hepatic blood inflow occlusion during hepatectomy may influence postoperative liver regeneration. The aim of this study was to investigate the influence of hepatic blood inflow occlusion on liver regeneration following partial hepatectomy in thioacetamide-induced cirrhotic rats.

METHODS

Forty-three cirrhotic Wistar-Furth rats were randomly assigned to three groups. Rats in group 1 underwent 64 per cent hepatectomy alone, those in group 2 were subjected to 15 min hepatic blood inflow occlusion followed by 64 per cent hepatectomy, and animals in group 3 were subjected to 30 min inflow occlusion followed by 64 per cent hepatectomy. Liver function, 5-bromo-2'-deoxyuridine (BrdU) labelling index and percentage of initial liver weight on days 1, 2 and 7 posthepatectomy were assessed.

RESULTS

Rats in groups 1 and 2 had a significantly higher serum albumin level and a markedly lower alanine aminotransferase level than animals in group 3 on day 1 posthepatectomy (P < 0.05). There was no significant difference in the serum level of total bilirubin of the three groups on days 1, 2 and 7. The BrdU labelling index was significantly higher in groups 1 and 2 than in group 3 animals on day 1 posthepatectomy (P < 0.01 and P < 0.05 respectively). Percentages of initial liver weight were similar in groups 1, 2 and 3 on days 1, 2 and 7 after hepatectomy.

CONCLUSION

Hepatic blood inflow occlusion for up to 30 min suppressed DNA synthesis and hepatocyte proliferation at an early posthepatectomy stage and consequently delayed recovery of liver function in cirrhotic rats. However, it did not affect restoration of liver mass or survival after 64 per cent hepatectomy.

A comprehensive karyotypic analysis on a newly developed hepatocellular carcinoma cell line, HKCI-1, by spectral karyotyping and comparative genomic hybridization

A continuously growing human hepatocellular carcinoma (HCC) cell line was established from a Chinese male, carrier of the hepatitis B virus (HBV). This cell line, designated HKCI-1, grows as an adhering monolayer of polygonal epithelial cells that embody one or more nuclei. HKCI-1 secretes alpha-fetoprotein but shows no evidence of HBV carriage. Conventional banding analysis of the short-term cultured primary tumor and the propagated HKCI-1 revealed a chromosome modal number of near-triploidy. It was, however, impossible to derive their complete karyotype due to the complex nature of chromosomal rearrangements and many marker chromosomes of uncertain origin. Spectral karyotyping (SKY) is a newly developed molecular cytogenetic technique that allows the unprecedented discernment of chromosomal abnormalities. Spectral karyotyping analysis on HKCI-1 and the primary tumor elucidated all aberrant chromosomes and revealed complex karyograms. Recurring aberrations detected in both primary tumor and HKCI-1 included der(X)t(X;11)(q10;p10), der(1)t(1;10)(q10;?pq), der(4)t(4;16)(p10;q10), i(5p), del(5)(q13), der(7)t(7;21)(q32q10::q10), der(8)t(8;17)(q10;p10), and der(9)t(9;22)(q34;?pq). Comparative genomic hybridization (CGH) was employed to monitor the culture evolution in vitro. Genomic imbalances in HKCI-1 involved chromosomal losses on 4q, 5q13-qter, 8p, 9pter-q33, 10q, 11q, 13q, 16q, 17q12-qter, and 22, and low-level gains on 6pter-q22, 7p, 8q, 9q34, 10p, 11p, 12, 17pter-q11.2, 18, 19, 20, 21, and Y. High-level amplifications were also detected on 5pter-q12, 7q11.2-qter, and Xq. The corresponding CGH finding on the primary tumor indicated similar imbalances. TP53 mutational analysis showed that both HKCI-1 and the primary tumor had the aflatoxin-associated mutation in codon 249 and an additional TP53 polymorphism in codon 72. Our present study demonstrates the value of combined SKY and CGH study in defining complex rearrangements and identifying cryptic translocations, and provides a comprehensive analysis on the chromosomal abnormalities in HKCI-1.

Systemic cytokine response after laparoscopic-assisted resection of rectosigmoid carcinoma: A prospective randomized trial

OBJECTIVE

To compare the systemic cytokine response in patients after laparoscopic-assisted resection with those after open resection of rectosigmoid carcinoma.

SUMMARY BACKGROUND DATA

Laparoscopic resection of colorectal carcinoma is technically feasible, but objective evidence of its benefit is scarce. Systemic cytokines are accepted as markers of postoperative tissue trauma and mediators of the host immune response.

METHODS

Thirty-four patients with rectosigmoid carcinoma, without evidence of metastatic disease and suitable for laparoscopic resection, were randomized to undergo either laparoscopic (n = 17) or conventional open (n = 17) resection of the tumor. Clinical parameters were recorded. Sera were collected before surgery and at appropriate time points afterward and assayed for interleukin-1beta, tumor necrosis factor-alpha, interleukin-6, and C-reactive protein. The primary end points were the cytokine and C-reactive protein levels. Data were analyzed by intention to treat.

RESULTS

The demographic data of the two groups were comparable. The clinical outcome of both groups was satisfactory, with no surgical deaths and a reasonable complication rate. Both interleukin-1beta and interleukin-6 levels peaked 2 hours after surgery, with the responses in the laparoscopic group significantly less than those in the open group. C-reactive protein levels peaked at 48 hours, and the difference was also statistically significant. Levels of tumor necrosis factor-alpha were not elevated after surgery, and there was no difference between the groups.

CONCLUSIONS

Tissue trauma, as reflected by systemic cytokine response, was less after laparoscopic resection than after open resection of rectosigmoid carcinoma. The difference in the systemic cytokine response may have implications on the long-term survival.

The use of liposucker for spleen retrieval after laparoscopic splenectomy

The retrieval of spleen after laparoscopic splenectomy has long been a problem. Frequently, it is necessary to extend the wound for retrieving the spleen intact and to prevent potential spillage of splenic tissue into the peritoneal cavity. We describe the application of the liposuction unit to remove the spleen piecemeal after laparoscopic splenectomy. We have found this technique easy to apply and safe, without the necessity of excessive wound extension, while preserving splenic tissue for histologic examination.

Laparoscopic-assisted abdominoperineal resection for low rectal adenocarcinoma

BACKGROUND

Laparoscopic-assisted resection for colorectal lesions is feasible, but most reported series are heterogeneous and noncomparative. The aim of this study was to investigate whether laparoscopic-assisted resection was better than open abdominoperineal resection for low rectal adenocarcinoma.

METHODS

Twenty-five (study group) of 59 consecutive patients who were considered suitable were selected for laparoscopic-assisted abdominoperineal resection based on the availability of informed consent, laparoscopic instruments, and experienced surgeons. The results in these patients were compared with the other 34 patients operated on by the open method (control group).

RESULTS

The median follow-up times for the study and control groups were 30.1 and 28.3 months, respectively. The operation time was significantly longer (t-test, p < 0.001), while operative blood loss (Mann-Whitney U test, p = 0.02), postoperative analgesic requirement (Mann-Whitney U test, p = 0.02), time to resume normal diet (Mann-Whitney U test, p = 0.04), and total hospital stay (Mann-Whitney U test, p = 0.02) were significantly less in the study than in the control group. The oncological clearance, complication rate, disease-free interval, and survival were comparable in the two groups.

CONCLUSIONS

Laparoscopic-assisted abdominoperineal resection allowed earlier postoperative recovery, with equal oncological clearance, morbidity, mortality, disease-free interval, and survival.

Spontaneous rupture of hepatocellular carcinoma: conservative management and selective intervention

HYPOTHESIS

A conservative approach using selective intervention is better than an aggressive approach using nonselective intervention for ruptured hepatocellular carcinoma.

DESIGN

Nonrandomized controlled trial.

SETTING

A university hospital.

PATIENTS AND INTERVENTIONS

From 1984 to 1990, an aggressive approach was adopted in which 29 and 8 of a total of 40 patients underwent surgical intervention or attempted transarterial embolization (TAE), respectively. From 1991 to 1997, a more conservative approach was used. The initial treatment for 72 patients was conservative with close monitoring. Additional hemostatic procedures consisting of TAE (n = 13) or surgical intervention (n = 9) were given, depending on the clinical progress, disease status, and liver function of the patients.

MAIN OUTCOME MEASURES

In-hospital mortality, survival.

RESULTS

In-hospital mortality rate was 62% (25 of 40 patients) in the first period and 51% (37 of 72 patients) in the second period. The respective median survival times were 7 and 12 days. If 36 patients with end-stage malignant neoplasms were excluded, the in-hospital mortality rate became 60% (18 of 30 patients) in the first period and 35% (16 of 46 patients) in the second period (P = .03, chi2 test). The respective median survival times became 8 and 72 days (P = .02, log rank test). In the second period, 7 (54%) of 13 patients who underwent TAE and 1 (11%) of 9 patients who underwent surgical intervention died within the same hospital admission (P = .07, Fisher exact test).

CONCLUSIONS

Selective intervention was cost-effective and gave better results than an aggressive approach. When intervention was indicated for hemostasis, surgery seemed better than TAE although the difference was not statistically significant.

Laparoscopic-assisted resection of right-sided colonic carcinoma: a case-control study

BACKGROUND AND OBJECTIVES

Laparoscopic-assisted resection of colorectal carcinoma is technically feasible. Whether it is beneficial to patients is uncertain. This study reviewed the results of laparoscopic-assisted resection in patients with right-sided colonic adenocarcinoma.

METHODS

We attempted laparoscopic-assisted right to extended right hemicolectomy in 28 patients with right-sided colonic carcinoma (study group). The results were compared with 56 matched patients who underwent conventional open resection in the same period (comparative group).

RESULTS

The median follow-up times for the study and comparative groups were 21.4 and 23.5 months, respectively. The operating time was significantly longer (t-test, P < 0.001), whereas the time to resuming normal diet (Mann-Whitney U-test, P < 0.001) and the duration of hospital stay (Mann-Whitney U-test, P = 0.002) were significantly less in the study than in the comparative group. The oncological clearance, in terms of the number of lymph nodes removed and the resection margins, the complication rate, the disease-free rate, and the survival rate were comparable in the two groups.

CONCLUSIONS

We conclude that laparoscopic-assisted resection of right-sided colonic adenocarcinoma has the advantage over open surgery of allowing earlier recovery. However, this is at the expense of a longer operating time.

Laparoscopic-assisted resection of right-sided colonic carcinoma: a case-control study

BACKGROUND AND OBJECTIVES

Laparoscopic-assisted resection of colorectal carcinoma is technically feasible. Whether it is beneficial to patients is uncertain. This study reviewed the results of laparoscopic-assisted resection in patients with right-sided colonic adenocarcinoma.

METHODS

We attempted laparoscopic-assisted right to extended right hemicolectomy in 28 patients with right-sided colonic carcinoma (study group). The results were compared with 56 matched patients who underwent conventional open resection in the same period (comparative group).

RESULTS

The median follow-up times for the study and comparative groups were 21.4 and 23.5 months, respectively. The operating time was significantly longer (t-test, P < 0.001), whereas the time to resuming normal diet (Mann-Whitney U-test, P < 0.001) and the duration of hospital stay (Mann-Whitney U-test, P = 0.002) were significantly less in the study than in the comparative group. The oncological clearance, in terms of the number of lymph nodes removed and the resection margins, the complication rate, the disease-free rate, and the survival rate were comparable in the two groups.

CONCLUSIONS

We conclude that laparoscopic-assisted resection of right-sided colonic adenocarcinoma has the advantage over open surgery of allowing earlier recovery. However, this is at the expense of a longer operating time.

Frequent allelic loss on chromosome 9 in hepatocellular carcinoma

Hepatocellular carcinoma (HCC) is a common malignancy worldwide and highly associated with chronic virus-B or -C infection and cirrhosis. Molecular studies have shown high frequency of loss of heterozygosity (LOH) in some specific chromosome regions, but LOH on chromosome 9 in HCC has not been thoroughly investigated. In our investigation of chromosome 9 with 19 polymerase-chain-reaction (PCR)-based polymorphic microsatellite markers, 30 of 48 HCC tissue samples (63%) had LOH, and a distinct common deletion region and a region of loss were identified. The first region was located at the 9p21 region and the minimal deletion region was located between loci D9S1747 and D9S1748. This is a region of approximately 200 kb which includes the p16 tumor-suppressor gene. A region of loss was located on 9p13 to 9q33. The putative tumor-suppressor gene for nevoid-basal-cell-carcinoma syndrome (NBCCS) at 9q22.3 resides within this region. In addition to LOH, 4 HCC cases showed possible homozygous deletions at 9p21 with markers D9S1748, D9S1752 and D9S171 by multiplex PCR analysis. In 3 cases, the minimal region of possible homozygous deletion was approximately 300 kb and was defined between markers D9S1747 and D9S1752. Since this deletion region includes both the p15 and the p16 tumor-suppressor genes, these genes were possibly inactivated by homozygous deletion in HCC. In addition, a second region of possible homozygous deletion was present on the centromeric side of 9p21. However, these changes are not associated with age, gender, size or tumor-cell differentiation. Our data also suggest that inactivation of the p16 and the p15 genes and the possibility of other unknown tumor-suppressor genes located on these defined deleted regions of chromosome 9 may be involved in the pathogenesis of HCC.

Frequent allelic loss on chromosome 9 in hepatocellular carcinoma

Hepatocellular carcinoma (HCC) is a common malignancy worldwide and highly associated with chronic virus-B or -C infection and cirrhosis. Molecular studies have shown high frequency of loss of heterozygosity (LOH) in some specific chromosome regions, but LOH on chromosome 9 in HCC has not been thoroughly investigated. In our investigation of chromosome 9 with 19 polymerase-chain-reaction (PCR)-based polymorphic microsatellite markers, 30 of 48 HCC tissue samples (63%) had LOH, and a distinct common deletion region and a region of loss were identified. The first region was located at the 9p21 region and the minimal deletion region was located between loci D9S1747 and D9S1748. This is a region of approximately 200 kb which includes the p16 tumor-suppressor gene. A region of loss was located on 9p13 to 9q33. The putative tumor-suppressor gene for nevoid-basal-cell-carcinoma syndrome (NBCCS) at 9q22.3 resides within this region. In addition to LOH, 4 HCC cases showed possible homozygous deletions at 9p21 with markers D9S1748, D9S1752 and D9S171 by multiplex PCR analysis. In 3 cases, the minimal region of possible homozygous deletion was approximately 300 kb and was defined between markers D9S1747 and D9S1752. Since this deletion region includes both the p15 and the p16 tumor-suppressor genes, these genes were possibly inactivated by homozygous deletion in HCC. In addition, a second region of possible homozygous deletion was present on the centromeric side of 9p21. However, these changes are not associated with age, gender, size or tumor-cell differentiation. Our data also suggest that inactivation of the p16 and the p15 genes and the possibility of other unknown tumor-suppressor genes located on these defined deleted regions of chromosome 9 may be involved in the pathogenesis of HCC.

Laparoscopic-assisted resection of colorectal carcinoma: five-year audit

INTRODUCTION

The place of laparoscopic-assisted colectomy for colorectal carcinoma is controversial. This study reviewed a consecutive series of patients who underwent laparoscopic-assisted resection of colorectal carcinoma in the past five years.

METHODS

Two hundred seventeen laparoscopic-assisted resections of colorectal carcinoma were attempted starting in April 1992. Initially, we only selected patients with metastatic disease or patients who were older than 65 years. Subsequently, both palliative and curative resections were attempted in patients with a suitable tumor, with no age limitation. Thus, all suitable patients were randomly assigned to received either laparoscopic-assisted or conventional open surgery.

RESULTS

Data collection was completed in 201 patients. In 22 patients open surgery was performed after a diagnostic laparoscopy. In the remaining 179 patients (90 males) in whom laparoscopic dissection was actually performed, the mean follow-up was 19.8 months, and the mean age was 66.3 years. The procedures performed included right hemicolectomy or extended right hemicolectomy (30 patients), transverse colectomy (2 patients), left hemicolectomy (3 patients), sigmoidectomy (48 patients), anterior resection (59 patients), and abdominoperineal resection (37 patients). Thirty-two (17.7 percent) procedures were converted to open surgery. The mean operation time was 203 minutes. The median blood loss was negligible, and the median requirement of transfusion was zero. The median number of postoperative parenteral analgesic injections was three. The median time to resume diet and hospital discharge were four and six days, respectively. The operative mortality was 1.7 percent. The survival rates at four years were 100, 88.3, and 64.5 percent for patients with Dukes A, B, and C disease, respectively. There was only one (0.65 percent) port-site recurrence.

CONCLUSION

Laparoscopic-assisted resection of colorectal carcinoma was technically feasible and safe. It allowed early postoperative recovery with satisfactory long-term survival. This is at the expense of a long operation. Its benefits over the conventional open technique await the results of the randomized trials.

High frequency of p16INK4A gene alterations in hepatocellular carcinoma

The tumor suppressor gene p16 (CDKN2/MTS-1/INK4A) is an important component of the cell cycle and inactivation of the gene has been found in a variety of human cancers. In order to investigate the role of p16 gene in the tumorigenesis of hepatocellular carcinoma (HCC), 48 cases of HCC were analysed for p16 alterations by: methylation-specific PCR (MSP) to determine the methylation status of the p16 promoter region; comparative multiplex PCR to detect homozygous deletion; PCR-SSCP and DNA sequencing analysis to identify mutation of the p16 gene. We found high frequency of hypermethylation of the 5' CpG island of the p16 gene in 30 of 48 cases (62.5%) of HCC tumors. Moreover, homozygous deletion at p16 region were present in five of 48 cases (10.4%); and missense mutation were detected in three of 48 cases (6.3%). The overall frequency of p16 alterations, including homozygous deletion, mutation and hypermethylation, in HCC tumors was 70.8% (34 of 48 cases). These findings suggest that: (a) the inactivation of the p16 is a frequent event in HCC; (b) the p16 gene is inactivated by multiple mechanisms including homozygous deletion, promoter hypermethylation and point mutation; (c) the most common somatic alteration of the p16 gene in HCC is de novo hypermethylation of the 5' CpG island; and (d) in contrast to other studies, high frequency of genomic alterations are not uncommon in the 9p21 of the p16 gene. Our results strongly suggest that the p16 gene plays an important role in the pathogenesis of HCC.

Detection of aberrant p16 methylation in the plasma and serum of liver cancer patients

We have studied the feasibility of detecting tumor-associated aberrant p16 methylation in the circulation of patients with hepatocellular carcinoma (HCC). We extracted DNA from the tumor tissues and peripheral blood plasma or serum of 22 HCC patients. p16 methylation was found in 73% (16 of 22) of HCC tissues using methylation-specific PCR. Among the 16 cases with aberrant methylation in the tumor tissues, similar changes were also detected in the plasma/serum samples of 81% (13 of 16) of the cases. No methylated p16 sequences were detected in the peripheral plasma/serum of the six HCC cases without these changes in the tumor, in 38 patients with chronic hepatitis/cirrhosis, or in 10 healthy control subjects. These results suggest that circulating liver tumor DNA may be detected using tumor-associated DNA methylation changes. Because methylation abnormalities have been found in many other genes and tumor types, this approach may have implications for the noninvasive detection of a wide variety of cancers.

Evacuation of the pleural cavity with an infant feeding catheter following en bloc resection of hepatocellular carcinoma and involved diaphragm--an institutional experience

En block resection of hepatocellular carcinoma and the involved diaphragm will, towards the end of operation, require evacuation of the pleural cavity, usually with a chest drain. We describe our method and experience of evacuating the pleural cavity, at the time of diaphragmatic repair, with an infant feeding catheter without the need of a chest drain. We have found the method safe and efficacious.

Randomized trial of early versus delayed laparoscopic cholecystectomy for acute cholecystitis

BACKGROUND

The aim of this prospective randomized study was to define the optimum management between early and delayed laparoscopic cholecystectomy for patients with acute cholecystitis.

METHODS

Patients were randomized to receive either early laparoscopic cholecystectomy within 24 h of randomization or initial conservative treatment followed by delayed laparoscopic cholecystectomy 6-8 weeks later.

RESULTS

There were 53 patients in the early group and 51 in the delayed group. There was no significant difference in conversion rate (early 21 per cent versus delayed 24 per cent), postoperative analgesic requirement (1 versus 2 doses) and postoperative complications. However, the early group had significantly longer operating time (122.8 versus 106.6 min, P = 0.04) and shorter total hospital stay (7.6 versus 11.6 days, P < 0.001).

CONCLUSION

Early laparoscopic cholecystectomy is safe and feasible for acute cholecystitis with the additional benefit of shorter total hospital stay. Apart from a shorter operating time, treating patients with delayed laparoscopic cholecystectomy does not offer additional benefit.

Food bolus intestinal obstruction in a Chinese population

BACKGROUND

The aim of the present study was to review the authors' experience of the diagnosis and management of food bolus obstruction in a Chinese population.

METHODS

During the period 1990-96, 31 patients were treated for food bolus obstruction. The records of these patients were retrospectively reviewed.

RESULTS

Eighteen patients (58%) had a history of previous gastric surgery and 13 patients (42%) had an intact gastrointestinal tract. The most common site of impaction was the terminal ileum, and a synchronous site of food bolus obstruction was present in 16% of cases. A total of 91% of the food bolus retrieved was phytobezoar. In 15 cases, the food bolus was successfully milked into the caecum. Enterotomy for removal was necessary in 12 patients, and two underwent small-bowel resection for necrosis.

CONCLUSION

Food bolus obstruction affects not only those who have had previous gastric surgery, but also a significant proportion of those with an intact gastrointestinal tract.

Interleukin-8 can mediate acute-phase protein production by isolated human hepatocytes

During the course of studies designed to identify the role of cytokines in the reprioritization of hepatic protein synthesis associated with cachexia we detected a hepatocyte-stimulating moiety in the supernatants of pancreatic cancer cells that was unrelated to interleukin (IL)-6. This study identifies that moiety as IL-8 and investigates the role of IL-8 in the induction of acute-phase protein production. The human pancreatic cancer cell line MIA PaCa-2 produced >1 ng/ml of IL-8 per 24 h, and supernatants from this cell line induced C-reactive protein (CRP) production from isolated human hepatocytes. Addition of neutralizing anti-human IL-8 antibody to such supernatants produced almost complete inhibition of CRP production. The addition of recombinant human IL-8 to hepatocytes resulted in a dose-dependent increase in CRP, alpha1-acid glycoprotein, and alpha1-antichymotrypsin production and a decrease in the production of transferrin and prealbumin. This study demonstrates that recombinant or tumor-derived IL-8 can modulate acute-phase protein production from isolated human hepatocytes and from human hepatoma cells.

Cell cycle arrest and induction of apoptosis in pancreatic cancer cells exposed to eicosapentaenoic acid in vitro

Eicosapentaenoic acid (EPA) has been shown to have an inhibitory effect on the growth of several pancreatic cancer cell lines in vitro. This study investigates the mechanism of growth inhibition and cytotoxicity of EPA on the pancreatic cancer cell line MIA PaCa-2. Cells were analysed for cell count, viability, cell cycle distribution and ultrastructural changes. There was a time- and dose-dependent decrease in cell count and viability in cultures of pancreatic cancer cells supplemented with EPA. Flow cytometric DNA analysis of MIA PaCa-2 cells incubated with EPA demonstrated the presence of sub G1 populations corresponding to the presence of apoptotic cells and the blockade of cell cycle progression in S-phase and G2/M-phase. The presence of apoptosis in EPA-supplemented cultures was further confirmed by DNA fragmentation and ultrastructural changes associated with apoptosis. Therefore, we conclude that EPA mediates its effect on the pancreatic cancer cell line MIA PaCa-2, at least in part, via cell cycle arrest and the induction of apoptosis.