Emerging Standards and the Hybrid Model for Organizing Scientific Events During and After the COVID-19 Pandemic.

Since the beginning of 2020, the coronavirus disease (COVID-19) pandemic has dramatically influenced almost every aspect of human life. Activities requiring human gatherings have either been postponed, canceled, or held completely virtually. To supplement lack of in-person contact, people have increasingly turned to virtual settings online, advantages of which include increased inclusivity and accessibility and a reduced carbon footprint. However, emerging online technologies cannot fully replace in-person scientific events. In-person meetings are not susceptible to poor Internet connectivity problems, and they provide novel opportunities for socialization, creating new collaborations and sharing ideas. To continue such activities, a hybrid model for scientific events could be a solution offering both in-person and virtual components. While participants can freely choose the mode of their participation, virtual meetings would most benefit those who cannot attend in-person due to the limitations. In-person portions of meetings should be organized with full consideration of prevention and safety strategies, including risk assessment and mitigation, venue and environmental sanitation, participant protection and disease prevention, and promoting the hybrid model. This new way of interaction between scholars can be considered as a part of a resilience system, which was neglected previously and should become a part of routine practice in the scientific community.

International Scientific Collaboration Is Needed to Bridge Science to Society: USERN2020 Consensus Statement.

Scientific collaboration has been a critical aspect of the development of all fields of science, particularly clinical medicine. It is well understood that myriads of benefits can be yielded by interdisciplinary and international collaboration. For instance, our rapidly growing knowledge on COVID-19 and vaccine development could not be attained without expanded collaborative activities. However, achieving fruitful results requires mastering specific tactics in collaborative efforts. These activities can enhance our knowledge, which ultimately benefits society. In addition to tackling the issue of the invisible border between different countries, institutes, and disciplines, the border between the scientific community and society needs to be addressed as well. International and transdisciplinary approaches can potentially be the best solution for bridging science and society. The Universal Scientific Education and Research Network (USERN) is a non-governmental, non-profit organization and network to promote professional, scientific research and education worldwide. The fifth annual congress of USERN was held in Tehran, Iran, in a hybrid manner on November 7-10, 2020, with key aims of bridging science to society and facilitating borderless science. Among speakers of the congress, a group of top scientists unanimously agreed on The USERN 2020 consensus, which is drafted with the goal of connecting society with scientific scholars and facilitating international and interdisciplinary scientific activities in all fields, including clinical medicine.

Adrenalectomy in Hong Kong: a critical review of adoption of laparoscopic approach.

BACKGROUND: A population-based study on adrenal surgery for treatment of adrenal diseases is still lacking. The aim of the present study is to evaluate the practice and the adoption of laparoscopic adrenalectomy (LA) in a stable population, as well as the potential impact of case volume on outcomes. METHODS: Patients undergoing elective adrenalectomy (n = 486) from 15 Hong Kong public hospitals over a 6-year period were reviewed. Patients undergoing LA (n = 353) were compared to those undergoing open adrenalectomy (n = 133). RESULTS: The overall number of adrenalectomies and the number and proportion of laparoscopic approach increased progressively during this period. The median operating time was similar but the median blood loss (50 mL vs 300 mL, P < .01) was less and the mean hospital stay (4.4 days vs 9.4 days) was shorter for LA. Smaller lesions tended to be selected for LA. There was no correlation between postoperative outcome with respect to length of stay and case volume for LA. CONCLUSIONS: The adoption of LA in Hong Kong hospitals was propagating progressively. Patients selected for LA had improved outcome although there seemed to be no significant correlation between postoperative outcome and case volume.

A randomized, controlled trial of postoperative adjuvant interferon therapy after resection of hepatocellular carcinoma.

OBJECTIVE: We conducted a randomized controlled trial of adjuvant interferon therapy in patients with predominantly hepatitis B-related hepatocellular carcinoma (HCC) to investigate whether the prognosis after hepatic resection could be improved. SUMMARY BACKGROUND DATA: Recurrence is common after hepatic resection for HCC. Interferon possesses antiviral, immunomodulatory, antiproliferative, and antiangiogenic effects and may be an effective form of adjuvant therapy. PATIENTS AND METHODS: Since February 1999, patients with no residual disease after hepatic resection for HCC were randomly assigned with stratification by pTNM stage to receive no treatment (control group), interferon alpha-2b 10 MIU/m (IFN-I group) or 30 MIU/m (IFN-II group) thrice weekly for 16 weeks. Enrollment to the IFN-II group was terminated from January 2000 because adverse effects resulted in treatment discontinuation in the first 6 patients. By June 2002, 40 patients each had been enrolled into the control group and IFN-I group. The baseline clinical, laboratory, and tumor characteristics of both groups were comparable. RESULTS: The 1- and 5-year survival rates were 85% and 61%, respectively, for the control group and 97% and 79%, respectively, for the IFN-I group (P = 0.137). After adjusting for the confounding prognostic factors in a Cox model, the relative risk of death for interferon treatment was 0.42 (95% CI, 0.17-1.05; P = 0.063). Exploratory subset analysis showed that adjuvant interferon had no survival benefit for pTNM stage I/II tumor (5-year survival 90% in both groups; P = 0.917) but prevented early recurrence and improved the 5-year survival of patients with stage III/IVA tumor from 24% to 68% (P = 0.038). CONCLUSION: In a group of patients with predominantly hepatitis B-related HCC, adjuvant interferon therapy showed a trend for survival benefit, primarily in those with pTNM stage III/IVA tumors. Further larger randomized trials stratified for stage are needed.

Tumor size and operative risks of extended right-sided hepatic resection for hepatocellular carcinoma: implication for preoperative portal vein embolization.

HYPOTHESIS: Major hepatic resection for hepatocellular carcinoma (HCC) is associated with high operative morbidity and mortality, especially in patients with underlying chronic liver disease. The present study evaluated the factors associated with increased operative risks in patients who underwent extended right-sided hepatic resection for HCC. DESIGN: Retrospective study. SETTING: Tertiary referral center. PATIENTS: A retrospective study was performed on 172 patients who underwent extended right-sided hepatic resection of more than 4 Couinaud segments for HCC during a 16-year period (January 1, 1989, to December 31, 2004) to evaluate the clinical factors associated with operative morbidity and mortality. MAIN OUTCOME MEASURE: Risk factors associated with hospital mortality and major operative morbidity. RESULTS: The overall major morbidity and hospital mortality rates were 14.0% and 8.1%, respectively. On multivariate analysis, small tumor size, conventional-approach hepatectomy, Child-Pugh grade B cirrhosis, and preexisting tumor rupture were the independent factors significantly associated with an increased risk of operative mortality. Discriminant analysis showed that a tumor size smaller than 10 cm significantly increased the risk of operative mortality compared with larger tumors (17.2% vs 3.5%; P = .046). CONCLUSIONS: Anterior approach is the preferred technique for extended right-sided hepatic resection for HCC. Increased risk of operative mortality was identified in patients who had a small tumor, which was associated with the resection of a large volume of functioning liver parenchyma. Preoperative portal vein embolization should be considered in this group of patients to enhance atrophy of the right lobe and hypertrophy of the future liver remnant to minimize the operative risk.

Comparable survival in patients with unresectable hepatocellular carcinoma treated by radiofrequency ablation or transarterial chemoembolization.

HYPOTHESIS: The survival benefits of radiofrequency ablation (RFA) and transarterial chemoembolization (TACE) are similar for patients with unresectable hepatocellular carcinoma amenable to either treatment. DESIGN: Retrospective comparative study. SETTING: Tertiary care institution. PATIENTS: From February 22, 2001, to March 10, 2004, 91 patients with unresectable hepatocellular carcinoma (tumor diameter <5 cm and <4 tumor nodules) treated by either TACE or RFA were analyzed from a prospective database. MAIN OUTCOME MEASURES: The treatment-related morbidity, mortality, overall survival, and time to disease progression. RESULTS: Forty patients received TACE and 51 patients received RFA during the study period. Demographic data were comparable in both groups of patients. The treatment-related morbidities of TACE and RFA were 10% and 28%, respectively (P = .04). There was no treatment-related mortality in either group. There was 1 patient (2%) with complete tumor remission in the TACE group, and the complete ablation rate in the RFA group was 96%. The time to disease progression was similar in both groups (P = .95). The overall survival rates at 1 and 2 years were 80% and 58%, respectively, in the TACE group and 82% and 72%, respectively, in the RFA group (P = .21). CONCLUSIONS: The overall survival and time for disease progression were similar in both groups of patients. In terms of the survival result, the efficacies of RFA and TACE were comparable for patients with unresectable hepatocellular carcinoma.

Radiofrequency ablation for hepatocellular carcinoma and metastatic liver tumors: a comparative study.

BACKGROUND: This study compared the effectiveness of radiofrequency ablation (RFA) for hepatocellular carcinoma (HCC) and liver metastases. METHODS: We compared the outcomes of 240 patients with HCC and 44 patients with liver metastases treated with RFA. Data were prospectively collected and retrospectively analyzed. Effects of different variables on recurrences were studied. RESULTS: A total of 406 tumor nodules were treated. The median size of the largest ablated tumor was 2.5 cm, and the median tumor number was 1. Complete tumor ablation was achieved in 91.2%. Local recurrence rate was 15.4% after a median follow-up of 24.5 months. There was no significant impact of tumor pathology on local recurrence. However, patients with liver metastasis had higher extrahepatic recurrence rate (P = 0.019) and shorter disease-free survival (P = 0.007). Patients with multiple tumors had higher local (P = 0.047) and extrahepatic (P = 0.019) recurrence rates than those with a solitary tumor. Tumor size had an impact on local recurrence rate only in patients with liver metastasis with a higher rate in those with tumor > 2.5 cm in diameter (P = 0.028). CONCLUSIONS: Tumor pathology does not appear to have a significant impact on local recurrence rates. RFA is effective in local tumor control for both HCC and liver metastasis.

A comparative study of routine laparoscopic versus open appendectomy.

OBJECTIVE: We evaluated the outcomes of routine laparoscopy and laparoscopic appendectomy (LA) in patients with suspected appendicitis. This is a retrospective study of the outcomes of patients undergoing laparoscopic appendectomy compared with outcomes for patients undergoing open appendectomy (OA) during the time that LA came into use. METHOD: Results of patients managed with routine laparoscopy and LA for suspected acute appendicitis were reviewed and analyzed. The preoperative and intraoperative findings were recorded. The clinical outcomes were compared with those of patients undergoing OA in the preceding 10 months. RESULTS: During the LA study period, 97 patients (47 men) with the median age of 34 years (range, 18 to 79) presented with clinical features of acute appendicitis. With the exclusion of 5 patients with open operations and 10 patients with other pathologies, 82 patients underwent laparoscopic appendectomy (Group A) for appendicitis. Thirty-one (37.8%) patients had complicated appendicitis (perforated or gangrenous appendicitis). Conversions were required in 6 patients (7.3%). During the OA period, 125 patients (57 men) with the median age of 42 (range, 19 to 79) years were operated on. With the exclusion of 6 patients with other pathologies, 119 underwent OA for acute appendicitis (Group B). Fifty-one (42.9%) had either perforated or gangrenous appendicitis. The median durations of surgery in Group A and Group B were 80 minutes (range, 40 to 195) and 60 minutes (range, 25 to 260), respectively (P < 0.005). Postoperative complication rates were comparable between the 2 groups (13.4% in Group A versus 15.8% in Group B). The median hospital stay for patients in Group A and Group B were 3.0 days (range, 1 to 47) and 4.0 days (range, 1 to 47), respectively (P = 0.037). CONCLUSIONS: We conclude that routine laparoscopy and LA for suspected acute appendicitis is safe and is associated with a significantly shorter hospital stay. Other intra-abdominal pathologies can also be diagnosed more accurately with the laparoscopic approach.

Safety limit of large-volume hepatic radiofrequency ablation in a rat model.

BACKGROUND: Large-volume hepatic radiofrequency ablation (RFA) has been used to treat large liver tumors, but its safety limit is unknown. This study aimed to investigate the possible systemic responses of large-volume hepatic RFA and to estimate its safety limit in normal and cirrhotic rats. HYPOTHESIS: Large-volume hepatic RFA causes a significant systemic inflammatory reaction. DESIGN: Experimental study. SETTING: University teaching hospital. INTERVENTION: Using the Cool-tip RF System (Radionics, Burlington, Mass), RFA was performed for different percentages of the liver volume by weight in normal and cirrhotic Sprague-Dawley rats. MAIN OUTCOME MEASURES: Changes in concentrations of serum inflammatory markers (tumor necrosis factor alpha [TNF-alpha] and interleukin [IL] 6), functions of various end organs, and survival rates were assessed. RESULTS: In the normal liver groups, the concentrations of TNF-alpha and IL-6 were significantly elevated in the early postoperative period when 50% (mean +/- SD TNF-alpha concentration, 130.3 +/- 15.6 pg/mL; mean +/- SD IL-6 concentration, 163.2 +/- 12.2 pg/mL) and 60% (mean +/- SD TNF-alpha concentration, 145.7 +/- 13.0 pg/mL; mean +/- SD IL-6 concentration, 180.8 +/- 11.0 pg/mL) of the liver volume were ablated compared with the control group (mean +/- SD TNF-alpha concentration, 30.4 +/- 9.9 pg/mL, P<.001; mean +/- SD IL-6 concentration, 28.4 +/- 6.7 pg/mL, P<.001). The concentrations of TNF-alpha and IL-6 in other groups remained similar to those in the control group. Thrombocytopenia, prolonged clotting time, and interstitial pneumonitis occurred when 50% and 60% of the liver volume were ablated. The 4-week survival rates were 100%, 60%, and 0% when 40%, 50%, and 60%, respectively, of the liver volume were ablated. Similar systemic inflammatory responses and poor survival rates were observed among the cirrhotic liver groups when 30% and 40% of the liver volume were ablated. CONCLUSIONS: The normal rats can tolerate RFA of 40% of the liver volume with minimal morbidity and no mortality whereas the cirrhotic rats can only tolerate 20% of the ablated liver volume. Beyond that limit, RFA would cause significant systemic inflammatory responses and poor survival.

Comparison of early endoscopic ultrasonography and endoscopic retrograde cholangiopancreatography in the management of acute biliary pancreatitis: a prospective randomized study.

BACKGROUND & AIMS: The role and potential benefits of endoscopic ultrasonography (EUS) in the management of acute biliary pancreatitis have not been documented. We report a large prospective randomized study comparing early EUS and endoscopic retrograde cholangiopancreatography (ERCP) in the management of these patients. METHODS: A prospective randomized study was performed on 140 patients with acute pancreatitis suspected to have a biliary cause. The patients were randomized to have EUS (n = 70) or ERCP (n = 70) within 24 hours from admission. In the EUS group, when EUS detected choledocholithiasis, therapeutic ERCP was performed during the same endoscopy session. In the ERCP group, diagnostic ERCP was performed, followed by therapeutic endoscopy when choledocholithiasis was detected. RESULTS: Examination of the biliary tree by EUS was successful in all patients in the EUS group, whereas cannulation of the common duct during ERCP was unsuccessful in 10 patients (14%) in the ERCP group (P = .001). Combined percutaneous ultrasonography and ERCP missed detection of cholelithiasis in 6 patients in the ERCP group. The overall morbidity rate was 7% in the EUS group, and that in the ERCP group was 14% (P = .172). The hospital stay and mortality rates were comparable in both groups. CONCLUSIONS: In selected patients with acute biliary pancreatitis, EUS could safely replace diagnostic ERCP in the management for selecting patients with choledocholithiasis for therapeutic ERCP with a higher successful examination rate, a higher sensitivity in the detection of cholelithiasis, and a comparable morbidity rate.

Variation in the use of laparoscopic cholecystectomy for acute cholecystitis: a population-based study.

HYPOTHESIS: There is wide variation in the use of laparoscopic cholecystectomy (LC) for acute cholecystitis among all public hospitals in Hong Kong. The objective of this study was to determine the factors responsible for the use of LC for acute cholecystitis in a stable population. DESIGN: A retrospective survey on 2353 patients with pathologically proven acute cholecystitis treated with cholecystectomy in Hong Kong from 1998 to 2002. SETTING: All public hospitals in Hong Kong. RESULTS: The rate of using LC for acute cholecystitis increased by 30.4% from 1998 to 2002. We observed a wide variation in the use of LC for acute cholecystitis ranging from 3.7% to 92.9% (P<.001). There was no correlation between the number of cholecystectomies performed and the percentage of LCs performed in each hospital (P = .39). Logistic regression analysis showed that the hospital, year of operation, and age of the patients were independent variables for LC. CONCLUSIONS: A wide variation in the use of LC for acute cholecystitis was observed among the public hospitals in Hong Kong. Young female patients from selected hospitals recently are more likely to be treated with LC.

Better survival in female patients with hepatocellular carcinoma: oral contraceptive pills related?

BACKGROUND: Hepatocellular carcinoma (HCC) has an indisputable male predominance. "Gender" as an independent prognostic factor for survival is, however, controversial. GOALS: Determine the influence of gender on survival in HCC patients, and identify factors that may account for the difference. METHODS: A retrospective analysis on a prospectively collected database in a 15-year period, from 1989 to 2003. RESULTS: A total of 3,171 HCC patients were managed in our institution (946 with curative treatment, 1,388 with palliative treatment, and 837 with supportive treatment) and studied. Female patients (n = 520) were 4.3 years older (P = 0.000), had a lower proportion of smokers and drinkers (P = 0.000), and were less likely to be hepatitis B carriers (P = 0.000). There was no difference in Child-Pugh status, tumor size, and the use of different treatments between genders. The overall median survival was 25.7 months longer in females after curative treatment (73.6 vs. 47.9 months; P = 0.012). The survival benefit in female patients was observed in early-stage diseases and persisted when only hepatitis B surface antigen-positive patients were analyzed (96.4 vs. 47.9 months; P = 0.044). With multivariate analysis, gender, indocyanine green test value at 15 minutes, number of tumor nodules, size of tumor, major vascular invasion, invasion of adjacent organs, and tumor rupture were the independent variables for survival. More importantly, in female patients, history of using oral contraceptive was an independent factor with survival benefit (P = 0.004). CONCLUSION: Gender is an independent variable for survival after curative treatment of HCC. A survival benefit was observed in females. History of using oral contraceptive is associated with a better long-term survival in female patients.

Porcine liver: morphologic characteristics and cell viability at experimental radiofrequency ablation with internally cooled electrodes.

PURPOSE: To evaluate morphologic characteristics and cell viability of radiofrequency ablation zones in porcine liver. MATERIALS AND METHODS: Approval of the study protocol was obtained from the Ethics Committee on Use of Live Animals for Teaching and Research at University of Hong Kong. Internally cooled electrodes were used to produce 120 ablated zones ex vivo and 60 ablated zones in vivo with single electrodes (1-, 2-, and 3-cm exposed lengths) or clustered electrodes (1.0-, 2.0-, and 2.5-cm exposed lengths) at 4, 8, 12, and 16 minutes of ablation (ex vivo) and 8 and 12 minutes of ablation (in vivo). Morphologic measurements of each ablated zone were performed. Cell viability in each ablated zone was assessed qualitatively with histochemical staining and quantitatively with measurement of intracellular adenosine 5'-triphosphate (ATP) concentration. RESULTS: Exposed length of electrode (coefficient = 0.79, standard error = 0.04, P < .001), duration of ablation (coefficient = 0.14, standard error = 0.01, P < .001), and clustered electrode design (coefficient = 1.21, standard error = 0.05, P < .001) were independent factors that affected minimal transverse diameter and volume of ablated zone in ex vivo study. Similar morphologic characteristics existed among ablated zones in in vivo study. Mean distance of ablation beyond the electrode tip remained constant (ex vivo, 1.0 cm +/- 0.08 [standard deviation]; in vivo, 0.5 cm +/- 0.05) regardless of different ablation conditions. Histochemical staining revealed no viable hepatocytes from center to margins of white zone in each ablated area. Mean intracellular ATP concentration in margins of white zone (9.5 x 10(-12) mol/microg DNA +/- 1.43) was lower than that in red zone (4088 x 10(-12) mol/microg DNA +/- 65.97, P < .001) and in adjacent normal liver (4528 x 10(-12) mol/microg DNA +/- 52.74, P < .001). CONCLUSION: Distance of ablation beyond the tip of the electrode remained constant (ex vivo, 1.0 cm; in vivo, 0.5 cm) with different conditions of ablation. Complete and uniform cellular destruction was achieved in the white zone of ablated area.

Selective portal vein clamping for radiofrequency ablation of hepatocellular carcinoma with portal vein invasion.

Surgical resection provides potential cure for patients with hepatocellular carcinoma. Unfortunately, resection is suitable in only about 10-37% of patients because of the limited hepatic functional reserve from the underlying chronic liver disease in the majority of patients. Survival of patients with unresectable diseases, especially those with portal vein tumor invasion, remains very poor. Radiofrequency ablation (RFA) is a form of locoregional therapy that allows a selected group of previously inoperable patients to be treated. However, problems with RFA leading to induced portal vein thrombosis have been reported in the literature. Nevertheless, patients with portal vein tumor invasion may be considered for radiofrequency tumor ablation to improve survival. We report the case of a patient with hepatocellular carcinoma with left portal vein invasion. Complete tumor ablation was achieved after RFA with left portal vein clamping. He remained disease free both radiologically and biochemically 6 months after the operation.

Hepatic actinomycosis presenting as a liver tumour: case report and literature review.

Hepatic actinomycosis poses a difficult problem in both diagnosis and management. We report the management of a patient with isolated hepatic actinomycosis, and review the clinical features and management of patients with hepatic actinomycosis mimicking liver tumour.

Improving perioperative outcome expands the role of hepatectomy in management of benign and malignant hepatobiliary diseases: analysis of 1222 consecutive patients from a prospective database.

OBJECTIVE: To assess the trends in perioperative outcome of hepatectomy for hepatobiliary diseases. METHODS: Data of 1222 consecutive patients who underwent hepatectomy for hepatobiliary diseases from July 1989 to June 2003 in a tertiary institution were collected prospectively. Perioperative outcome of patients in the first (group I) and second (group II) halves of this period was compared. Factors associated with morbidity and mortality were analyzed. RESULTS: Diagnoses included hepatocellular carcinoma (n = 734), other liver cancers (n = 257), extrahepatic biliary malignancies (n = 43), hepatolithiasis (n = 101), benign liver tumors (n = 61), and other diseases (n = 26). The majority of patients (61.8%) underwent major hepatectomy of > or = 3 segments. The overall hospital mortality and morbidity were 4.9% and 32.4%, respectively. The number of hepatectomies increased from 402 in group I to 820 in group II, partly as a result of more liberal patient selection. Group II had more elderly patients (P = 0.006), more patients with comorbid illnesses (P = 0.001), and significantly worse liver function. Nonetheless, group II had lower blood loss (median 750 versus 1450 mL, P < 0.001), perioperative transfusion (17.3% versus 67.7%, P < 0.001), morbidity (30.0% versus 37.3%, P = 0.012), and hospital mortality (3.7% versus 7.5%, P = 0.004). On multivariate analysis, hypoalbuminemia, thrombocytopenia, elevated serum creatinine, major hepatic resection, and transfusion were the significant predictors of hospital mortality, whereas concomitant extrahepatic procedure, thrombocytopenia, and transfusion were the predictors of morbidity. CONCLUSIONS: Perioperative outcome has improved despite extending the indication of hepatectomy to more high-risk patients. The role of hepatectomy in the management of hepatobiliary diseases can be expanded. Reduced perioperative transfusion is the main contributory factor for improved outcome.

Pancreaticoduodenectomy with en bloc portal vein resection for pancreatic carcinoma with suspected portal vein involvement.

Pancreaticoduodenectomy combined with portal vein resection is increasingly accepted as a viable treatment option for pancreatic carcinoma with suspected involvement of the portal vein.However, its clinical benefit remains controversial. This study evaluated the outcomes of pancreaticoduodenectomy with portal vein resection for pancreatic carcinoma in a group of Chinese patients operated on by a specialized team in a center with a low case volume of pancreatic cancer. The perioperative and long-term outcomes of 12 patients with portal vein resection for suspected involvement of the portal vein and 38 patients who underwent pancreaticoduodenectomy without portal vein resection during the same period were compared. In the former group, eight patients underwent segmental resection, and four patients underwent wedge resection of the portal vein. There were no significant differences in operative blood loss (median 0.8 vs. 0.8 liter, p = 0.313), hospital mortality (0% vs. 2.6%, p = 1.000), or operative morbidity (41.7% vs. 42.1%, p = 0.979) between the two groups. Patients who required portal vein resection had higher frequencies of microscopic lymphatic permeation (58.3% vs. 18.4%, p = 0.023) and vascular invasion (50.0% vs. 15.8%, p = 0.025). Long-term survival was comparable between patients with portal vein resection and those without it (median 19.5 vs. 20.7 months,p = 0.769). These findings suggest that pancreaticoduodenectomy combined with portal vein resection can be performed safely by a specialized team in a center with a low case volume of pancreatic carcinoma and that it may offer survival benefit in patients with suspected portal vein involvement.

Management of hepatocellular carcinoma in renal transplant recipients.

BACKGROUND AND OBJECTIVE: In Hong Kong where hepatitis B virus (HBV) infection is endemic, hepatocellular carcinoma (HCC) accounts for 20% of all malignant transformations in renal transplant recipients. The aim of the present study was to review the management and outcome of HCC in renal transplant recipients at a specialized surgical center. METHOD: A retrospective analysis on the data collected prospectively in a tertiary referral center. RESULTS: From January 1991 to December 2002, five renal transplant recipients were diagnosed to have primary HCC and received treatment in our center. There were four men and one woman with a median age of 47 (range, 38-68) years. Four of them had cadaveric renal transplantation whereas one had live donor transplantation. All of them were HBV carriers. The median tumor size was 3.5 cm (range, 1.8-8 cm). All tumors, except one, were diagnosed in sub-clinical stage by surveillance serum alpha-fetoprotein assay and percutaneous ultrasonography. Four patients were treated with surgical resection and one received transarterial oily chemoembolization (TOCE) as their primary treatments. There was one peri-operative death and the remaining three surgically treated patients were alive 4, 62, and 64 months after the resection. One patient developed recurrence 18 months after curative resection and was treated with TOCE. The patient with unresectable disease was alive for 50 months after the initial diagnosis. The surgical resection and overall survival rates of these patients were better than the published results. CONCLUSION: Early detection with regular serum alpha-fetoprotein assay and ultrasonographic study, vigilant care in the peri-operative period, long-term follow-up for detection and treatment of recurrence, as well as close collaboration between renal physicians and liver surgeons may improve the outcome of treatment of HCC in renal transplant recipients.

Comparison of systemic responses of radiofrequency ablation, cryotherapy, and surgical resection in a porcine liver model.

BACKGROUND: The degree of systemic response after hepatic radiofrequency ablation (RFA) has not been well investigated. METHODS: An in vivo study was conducted on 23 domestic swine. Different hepatic procedures (RFA, cryotherapy, hepatic pedicle ligation, and hepatectomy) were performed on the medial lobe of the liver (30% of the liver volume). Systemic responses in terms of systemic inflammatory marker changes and end-organ functions were determined. RESULTS: During the early postoperative period, the systemic inflammatory marker concentrations (tumor necrosis factor-alpha and interleukin-1beta) in the RFA group were significantly lower than in the cryotherapy group but significantly higher than in the control group. The corresponding concentrations in the hepatectomy group remained similar to those in the control group. The pattern of changes of serum inflammatory marker concentrations in the pedicle ligation group followed the pattern in the RFA group. The serum intracellular content concentrations (lactate dehydrogenase and urate) of the cryotherapy group peaked at 6 hours after operation, which was significantly later than in the other groups. Liver function, renal function, and coagulation profiles remained normal in the RFA group. However, the renal function deteriorated in the cryotherapy group on day 1. Both platelet count and activated clotting time showed significant derangement in the cryotherapy group compared with the control group. There was more severe interstitial pneumonitic change of the porcine lung after cryotherapy than after RFA. CONCLUSIONS: The systemic responses of RFA were significantly less severe than those of cryotherapy in this porcine model. However, the increase in serum inflammatory markers and pneumonitis after RFA was substantial when compared with hepatectomy.

Inflammatory pseudotumor of the liver in association with a gastrointestinal stromal tumor: a case report.

Inflammatory pseudotumor of the liver is a rare benign lesion that can mimic a malignant liver neoplasm. A case of inflammatory pseudotumor of the liver found in association with a malignant gastrointestinal stromal tumor (GIST) of the small bowel was reported. The inflammatory pseudotumor was misdiagnosed as a metastasis from the GIST by frozen section. A correct diagnosis was made only after histopathological examination of the paraffin section of the resected specimen. This case is particularly interesting because of the association of the two rare pathological entities and the diagnostic dilemma that arose from the similarity of their histological appearances. To our knowledge, this association has not been reported in the literature.