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C C Loong

Publications and source records attributed to C C Loong.

At least 19 recordsLinked to original sources
PubMed2004

Antioxidant supplementation may improve renal transplant function: a preliminary report.

Dysfunction of the renal graft may not only be due to rejection but also other causes such as ischemia and reperfusion injury and calcineurin inhibitor nephrotoxicity. Antioxidant free radical scavengers may decrease oxidative stress and lipid peroxidation. Previous animal studies suggest that vitamins C (ascorbic acid) and E (alpha-tocopherol) are both strong antioxidants, that decrease oxidative stress caused by ischemia-reperfusion injury and calcineurin inhibitor nephrotoxicity. But there have been only limited reports about clinical efficacy. We report five cases supplemented with vitamin C (500 mg per day), vitamin E (500 mg per day), or both. After a 1- to 3-month prescription, the serum creatinine level decreased more than 20% from the original value. Interestingly, one patient had this experience: he ceased vitamin E for 1 month due to noncompliance. The serum creatinine level increased more than 50%. When he took vitamin E again, his serum creatinine level declined and returned to the previous level. From our limited experience, antioxidant supplementation with vitamin C or E may improve renal transplant function, especially in grafts donated from marginal donors.

Adult↗
PubMed2004

Reliability of contemporary radiology to measure tumour size of hepatocellular carcinoma in patients undergoing resection: limitations and clinical implications.

BACKGROUND: Preoperative radiology has been widely used to detect and measure hepatocellular carcinoma (HCC). However, its accuracy and reliability are unclear. This study aimed to assess the ability of current radiology to measure tumour size in patients undergoing resection. METHODS: We evaluated 212 HCC patients undergoing curative resection. Tumour size measured in the pathological examination was correlated with that obtained in preoperative ultrasound (US) and contrast-enhanced dynamic computed tomography (CT). Accuracy and association with tumour recurrence were investigated. RESULTS: The mean size of the tumour was 4.5 +/- 2.6 cm and was accurate in both US and CT in only 6 (3%) patients. Cirrhosis (P = 0.015), absence of tumour stain (P = 0.002) and small (< or = 4 cm) tumour (P < 0.001) were the significant factors associated with size deviation using both US and CT. Ninety-four (44%) patients developed tumour recurrence within 17 +/- 11 months of resection. Recurrence rate was 52%, 52% and 67% in patients with underestimation in US (relative risk [RR]: 2.0, 95% confidence interval [CI]: 1.2-3.4, P = 0.01), CT (RR: 2.1, 95% CI: 1.1-4, P = 0.022) and both modalities (RR: 2.5, 95% CI: 1.4-4.2, P = 0.001), respectively, compared to 30% recurrence in patients with accurate estimation of tumour size. CONCLUSION: The accuracy of radiology in measuring tumour size was poor, and may lead to inappropriate treatment. The finding that underestimation of tumour size was associated with a higher tumour recurrence rate is consistent with the hypothesis that HCC may recur from pre-existing tumour foci which could not be identified from the current imaging modalities.

Aged↗
PubMed2001

IL-17 expression as a possible predictive parameter for subclinical renal allograft rejection.

In the present study we have tried to establish the role of IL-17 in subclinical renal allograft rejection. In this animal model, renal grafts from BN (RT1n) were transplanted heterotopically into LEW (RT1l) rats. As controls, LEW grafts were transplanted into LEW rats. The histopathological examination demonstrated that the changes in the allograft kidney on day 2 were similar to those ranked as borderline changes according to the Banff classification scale. On day 2, the serum level of blood urea nitrogen (BUN) and creatinine were the same as on day 1. The examination of allograft cytokines mRNA showed that IL-17 mRNA expressed earlier on the second postoperative day, peaked at day 5, and then declined, becoming almost undetectable at day 9, when most rats died. IL-17 antigen was also proven, by histochemical staining, to be expressed early, however we could not find the same early appearance on other Th1/Th2 cytokines. In human renal biopsy samples, the IL-17 antigen could be found scattered around in the borderline changed rejected renal allografts without evidence of a serum creatinine increase, but was undetectable both in normal controls and in renal transplant tissue without signs of rejection. IL-17 mRNA was detected in the mononuclear cells of the urinary sediment of patients suffering from borderline subclinical rejection. From the above results we can hypothesize that IL-17 could serve as a predictive parameter for borderline subclinical renal allograft rejection in the future.

Animals↗
PubMed2001

Kidney transplantation in patients with chronic hepatitis B virus infection: is the prognosis worse?

The impact of hepatitis B virus (HBV) infection on the long-term outcome of kidney transplant patients is controversial. A total of 34 chronic hepatitis B surface antigen (HBsAg) carriers among 143 renal allograft recipients were identified in this study (mean follow-up period: 5.6+/-3.3 years; range: 1-13 years). During the follow-up, one HBsAg-positive recipient with preexisting cirrhosis died of liver failure, and seven (21%) others developed serious HBV-related complications (four fulminant hepatitis, two hepatocellular carcinoma, one cirrhosis), and four died. Although HBsAg-positive recipients had a higher rate of liver-related complications and deaths than HBsAg-negative recipients did, there were no significant differences in the long-term graft and patient survival between the two groups. The survival rates, liver-related complications, and deaths in HBsAg-positive allograft recipients and 28 HBsAg-positive uremic patients under dialysis were similar. In conclusion, HBV infection is not a contraindication to kidney transplantation. However, pretransplant candidates should be warned of potentially serious liver-related complications.

Adolescent↗
PubMed2001

Clinicopathologic and prognostic differences between patients with hepatitis B- and C-related resectable hepatocellular carcinoma.

BACKGROUND AND PURPOSE: Hepatitis B and C viral infections are important factors in the development of hepatocellular carcinoma (HCC). This study examined the clinicopathologic and prognostic differences in patients with hepatitis B- and C-related resectable HCC. METHODS: A total of 270 HCC patients who underwent hepatic resection were enrolled. Among these patients, 211 were positive for hepatitis B surface antigen (HBsAg) and 59 were positive for anti-hepatitis C virus antibody (anti-HCV). The clinical manifestations, pathologic features, and treatment outcomes were compared between the HBsAg-positive and anti-HCV-positive groups. RESULTS: Compared to anti-HCV-positive patients, HBsAg-positive patients were significantly younger, had a higher familial incidence of HCC, larger tumor size, and a higher incidence of multiple tumors. HCC patients who were anti-HCV positive had worse liver function and a higher incidence of history of blood transfusion. DNA flow cytometric analysis revealed significantly more proliferative activity in the non-tumor part of the liver in HBsAg-positive HCC patients. The 1-, 3-, and 5-year overall survival rates of HBsAg-positive patients were 79%, 57%, and 48%, respectively, and for anti-HCV-positive patients were 91%, 75%, and 62%, respectively. HBsAg-positive patients had a significantly lower overall survival rate than anti-HCV-positive patients (p = 0.018). CONCLUSIONS: HBsAg-positive patients with resectable HCC had a less favorable survival rate after tumor resection than anti-HCV-positive HCC patients. This survival difference might have been related to the relatively advanced stage of disease and the higher proliferative activity of the non-tumor part of the liver in HBsAg-positive HCC patients.

Adult↗
PubMed2000

Surgical results in patients with hepatitis B-related hepatocellular carcinoma and positive hepatitis B early antigen.

Hepatitis B virus (HBV) infection is the major risk factor in the pathogenesis of hepatocellular carcinoma (HCC). Patients who are positive for hepatitis B early antigen (HBeAg) have active liver disease. The present study aimed to evaluate the possible role of HBeAg in patients with resectable HCC. A series of 249 HCC patients with complete preoperative hepatitis marker who had undergone potentially curative resection were enrolled. Patients with hepatitis C virus infection were excluded. Of these patients, 27 were positive for hepatitis B surface antigen (HBsAg) and HBeAg (group I), 171 were positive for HBsAg and negative for HBeAg (group II), and 51 were negative for hepatitis B markers (group III). The clinicopathologic features and postoperative survivals were compared among the three groups. The prevalence of HBeAg was 10.8%. Group I patients were significantly younger and had worse liver function, smaller tumors, and a higher incidence of liver cirrhosis and chronic active hepatitis than those in groups II and III. No increase in tumor invasiveness was noted in group I patients. The operative morbidity, mortality, and postresection survival were comparable among the three groups. Our findings indicated that HBeAg positivity is not a negative factor for resection in HCC patients and has no significant influence on postresection survival.

Aged↗
PubMed2000

Perioperative safety and prognosis in hepatocellular carcinoma patients with impaired liver function.

BACKGROUND: The benefits of liver resection for hepatocellular carcinoma (HCC) patients with concomitant impaired liver function were often considered questionable because of poor postoperative prognosis. This study will clarify whether an acceptable operative risk exists and whether limited resection will compromise the outcomes of these patients. STUDY DESIGN: Between July 1991 and December 1996, a total of 168 patients with HCC who underwent hepatectomies were enrolled and divided into normal (group A) and impaired (group B) liver function groups according to the value of indocyanine green retention rate at 15 minutes. Clinical features, surgical related features, pathologic features, and disease-free and overall survivals were compared between the groups. RESULTS: Operative morbidity and mortality in group A were 27.3% and 1.6%, and in group B were 40.0% and 2.5%, respectively (p = 0.129 and 0.506). Disease-free survival and overall survival at 5 years in group A were 43.2% and 59.6%, respectively, and in group B they were 30.6% and 56.8%, respectively (p = 0.607 and 0.378). CONCLUSIONS: Limited liver resection is safe and provides favorable prognosis in HCC patients with concomitant impaired liver function.

Adult↗
PubMed2000

Clinical significance of microscopic tumor venous invasion in patients with resectable hepatocellular carcinoma.

BACKGROUND: Tumor venous invasion in patients with resectable hepatocellular carcinoma (HCC) is frequent and can be macroscopic and microscopic or microscopic alone. Although macroscopic invasion is a well-established prognostic indicator, the clinical significance of microscopic invasion remains unclear. METHODS: There were 322 patients enrolled who had undergone curative resection for HCC. The clinicopathologic factors and prognostic significance associated with macroscopic and microscopic venous invasion were analyzed. RESULTS: Macroscopic invasion was observed in 50 patients (15.5%) and microscopic invasion in 190 (59.0%). The larger the tumor, the more the incidence of venous invasion. There were 140 patients with microscopic invasion only (Group 1). Patients with macroscopic invasion (Group 2, n = 50) also had microscopic invasion. Compared with patients without venous invasion (Group 3, n = 132), Group 1 had a higher alpha-fetoprotein level, a larger tumor size, and more tumors without encapsulation. For group 1, the 1-, 3-, and 5-year disease-free survival rates were 65.6%, 41.6%, and 30.8%, respectively. The 1-, 3-, and 5-year overall survival rates were 87. 8%, 60.0%, and 52.7%, respectively. The survival rates of group 1 were lower than those of group 3 and higher than those of group 2 (P <.05). Multivariate analysis indicated that microscopic and macroscopic venous invasion, surgical margin, indocyanine-green retention, and tumor size and number were significant predictors of postresectional survival. CONCLUSIONS: In HCC patients, microscopic venous invasion is frequent and related independently to postresectional outcome.

Aged↗
PubMed2000

Serum interleukin-10 but not interleukin-6 is related to clinical outcome in patients with resectable hepatocellular carcinoma.

OBJECTIVE: To evaluate the clinical significance of preoperative serum levels of interleukin-10 (IL-10) and interleukin-6 (IL-6) in patients with resectable hepatocellular carcinoma (HCC). SUMMARY BACKGROUND DATA: IL-10 is an immunosuppressive factor and IL-6 is a multifunctional cytokine that plays a role in host defense mechanisms. Both have been reported to be related to the disease prognosis in some human solid tumors. Their role in human HCC has not been investigated. METHODS: Preoperative serum samples of 67 patients with HCC who underwent potentially curative resection and 27 normal healthy donors were assayed. Levels of IL-10 and IL-6 were determined by enzyme-linked immunosorbent assay. The clinical significance of serum IL-10 and IL-6 was evaluated and compared with conventional clinicopathologic factors. RESULTS: Levels of IL-10 and IL-6 were significantly higher in patients with HCC than in healthy subjects. There was no correlation between IL-10 and IL-6 levels. Tumor resection resulted in a decrease in IL-10 and IL-6 levels. On univariate analysis, patients with high IL-10 levels had a worse disease-free survival, but IL-6 levels had no correlation with the disease-free survival. Multivariate analysis identified IL-10 levels as a predictor of postresectional outcome, in addition to the well-established clinical risk factors. CONCLUSIONS: In patients with HCC, the preoperative serum IL-10 level is related to the clinical outcome. IL-10 may play an important role in the progression of HCC.

Carcinoma, Hepatocellular↗
PubMed2000

Renal allograft dysfunction associated with rifampin-tacrolimus interaction.

OBJECTIVE: To report an interaction between tacrolimus and rifampin with subsequent adverse effects on renal allograft function. CASE SUMMARY: A 61-year-old Chinese man received a cadaveric renal transplant in 1991. Progressive deterioration of allograft function developed during the following six years while the patient was receiving cyclosporine and prednisolone. In January 1998, tacrolimus was substituted for cyclosporine for late biopsy-proven graft rejection, with target trough blood concentrations between 5 and 8 ng/mL. After conversion, serum creatinine fell to 2.0 mg/dL; the nadir was reached within one year. At the same time, rifampin was instituted for controlling tuberculosis and empiric fluconazole was discontinued. Twelve days later, the patient's serum creatinine concentration rose to 2.9 mg/dL and tacrolimus concentration fell to 1.5 ng/mL, along with oliguria. These findings suggested acute rejection, which was successfully reversed by steroid therapy. However, more than a tenfold increase in the tacrolimus dosage was required to maintain the same concentrations during subsequent months, accompanied by an increase in serum creatinine (from 2.0 to 2.6 mg/dL) and decrease in urine excretion. Biopsy at this time demonstrated acute rejection (Banff I), chronic allograft nephropathy (Banff II), and suspected tacrolimus nephrotoxicity. After unsuccessful methylprednisolone recycling, mycophenolate mofetil was introduced to control rejection and facilitate reduction of the tacrolimus dosage to minimize its nephrotoxicity. CONCLUSIONS: As a potent CYP3A4 isoenzyme inducer, rifampin coadministration caused the abrupt decrease in tacroiimus blood concentrations, leading to an approximate tenfold increase in its daily dose, which may be important to subsequent allograft dysfunctions.

Antibiotics, Antitubercular↗
PubMed2000

Impact of hepatitis B and C virus infection on the outcome of kidney transplantation in Chinese patients.

BACKGROUND: There has been improvement in kidney transplantation over the years; however, the impact of hepatitis B and C virus (HBV, HCV) infection on the long-term outcome of kidney transplant is still controversial. METHODS: A total of 113 patients who received renal allografts from 1986 to 1998 were analyzed. Nine were positive for both hepatitis B surface antigen (HBsAg) and antibody to HCV (anti-HCV) (Group 1), 20 were HBsAg-positive and anti-HCV-negative (Group 2), 30 were HBsAg-negative and anti-HCV-positive (Group 3) and 54 were negative for both markers (Group 4). The outcome and survival were compared among the four groups of patients. RESULTS: The mean follow-up period was 5.1 +/- 3.2 years (range, 0.5-13 years) for all patients. Group 2 patients had significantly higher liver-related complications (35% vs 0%, p < 0.0001) and liver-related deaths (20% vs 0%, p = 0.004) than did Group 4 patients. Among all, four HBsAg-positive patients had fulminant hepatitis and died within two years of transplantation. Three (Group 2) of the patients who died were seropositive for hepatitis B e antigen and/or HBV DNA and none had a history of or positive serologic marker to indicate hepatitis of other etiologies. The remaining patient (Group 1) had evidence of superinfection of HCV. Liver cirrhosis occurred in one, two and one patient in Groups 1, 2 and 3, respectively, and hepatocellular carcinoma occurred in two and one patient in Groups 2 and 3, respectively. Despite high liver-related mortality in HBV-infected patients, paradoxically, no significant differences among the four groups in the long-term graft and patient survivals were demonstrated. The presence of HBsAg or anti-HCV was not associated with a poor prognosis of survival as determined by Cox regression analysis. CONCLUSIONS: HBV or HCV infection is not a contraindication to kidney transplantation in Chinese patients. However, it should be noted that serious liver-related complications may occur and limit survival in HBV- and/or HCV-infected patients after kidney transplantation.

Adolescent↗
PubMed1999

Evaluation of a simplified staging system for prognosis of hepatocellular carcinoma.

The current TNM (tumor, nodes, metastases) staging system for human hepatocellular carcinoma (HCC) has been challenged since a new T staging system was proposed to correlate the staging group with patient outcome after curative liver resection. The new T staging system proposed T1 as no vascular invasion, small size (< or = 5 cm), and solitary tumor. T2 was defined as the presence of one of the following factors: size greater than 5 cm, vascular invasion, or multiple tumors; T3 as the presence of two of the above three factors; and T4, the presence of all three factors. A total of 323 patients undergoing curative partial hepatectomy for HCC were studied. Kaplan-Meier survival analysis was used to evaluate the postoperative outcome. The new T staging showed good correlation between the staging group and patient outcome. The 1-year disease-free survival (DFS) rate and overall survival (OS) rate were 80.0% and 87.8% for stage 1 (n = 115), 67.6% and 81.6% for stage 2 (n = 136), 40.0% and 58.0% for stage 3 (n = 58), and 21.4% and 42.8% for stage 4 (n = 14), respectively. The 3-year DFS rate and OS rate were 61.0% and 64.5% for stage 1, 37.8% and 50.7% for stage 2, 21.4% and 29.8% for stage 3, and 21.4% and 34.3% for stage 4, respectively. When analyzed using the current International Union Against Cancer (UICC) pathologic (p) TNM staging system, the 1-year and 3-year DFS rates were 86.2% and 64.0% for stage 1 (n = 30), 73.9% and 50.0% for stage 2 (n = 182), and 46.8% and 22.3% for stage 3 (n = 111), respectively. Our results showed that, while both staging systems allow clear stratification of patients into prognostic groups, the modified TNM system is not superior to the UICCpTNM system in predicting survival of HCC patients after curative partial hepatectomy. A larger scale, multicenter study may be needed to test the revised TNM system.

Carcinoma, Hepatocellular↗
PubMed1997

Class I and class II major histocompatibility complex antigens expression on human hepatocytes and hepatoma cells: an approach with high sensitivity and specificity.

The expression of gene products of the major histocompatibility complex (MHC) on the cell surface is known to play an important role in immunological responses. While some studies have reported the presence of MHC antigens on hepatocytes, information about specific, sensitive hepatocyte MHC antigen expression in various liver diseases is minimal. To investigate the expression of class I and class II MHC antigens on hepatocellular carcinoma (HCC) specimens, two-color flow cytometry was used to demonstrate MHC antigen expression on non-malignant and malignant hepatocytes using the hepatocyte-specific monoclonal antibody (MAb) 9B2 for selective gating and either MHC-specific W6/32 (class I) or Q5/13 (class II) MAb for MHC antigen detection. Non-malignant liver tissues demonstrated variable MHC antigen expression. Malignant hepatocytes isolated from resected HCC specimens as well as non-tumorous hepatocytes from these HCC specimens also disclosed various degrees of MHC antigen expression. Although we were not able to demonstrate a clear correlation between clinical outcome and MHC antigen expression in HCC, we conclude that the expression of MHC antigens on human hepatocytes and hepatoma cells can be accurately detected by flow cytometry using hepatocyte-specific MAb for selective gating and MHC-specific MAbs. Of note, two cases of non-malignant fetal liver tissues indicated that >95% of fetal hepatocytes expressed class I MHC antigens and <25% of fetal hepatocytes expressed class II MHC antigens. These findings may lead to further investigations into the progression of HCC cells or into the possible mechanisms of the hepatocellular carcinogenesis.

Antibodies, Monoclonal↗
PubMed1997

Prognostic significance of surgical margin in hepatocellular carcinoma resection: an analysis of 165 Childs' A patients.

BACKGROUND AND OBJECTIVES: The clinical significance of the width of the surgical margin in the resection of hepatocellular carcinoma (HCC) has yet to be clarified. METHODS: Childs' A patients (165) who underwent resections of HCC were studied. Patients were divided into a wide margin group (1.0 cm or more, group W, n = 85), and a narrow margin group (< 1.0 cm, group N, n = 80). RESULTS: Multivariate analysis showed that preoperative alpha-fetoprotein level (P = 0.0202), venous invasion (P = 0.0226), surgical margin (P = 0.0012), and TNM stage (P = 0.0023) were significant predictors of disease-free survival. By the log-rank test, the disease-free survival rate of the group W patients was significantly higher than that of the group N patients (P = 0.0007). Group N had a higher percentage of patients undergoing minor resection (wedge resection or subsegmentectomy) (44% vs. 26%, P = 0.016) and had a higher percentage of patients with centrally located tumor (62% vs. 29%, P = 0.000) than group W. CONCLUSIONS: The results of this study indicated the significant influence of surgical margin on HCC recurrence after resection. Minor resection and centrally located tumor are factors related to a narrow surgical margin.

Adult↗
PubMed1997

Diagnostic laparoscopy: indication and benefit.

BACKGROUND: Patients with an obscure and unrelievable abdominal condition may be forced to receive open laparotomy for diagnosis. Diagnostic laparoscopy has been suggested as an alternative to diagnostic laparotomy in selected cases. The aim of this article is to evaluate the circumstances suitable for laparoscopic diagnosis of certain abdominal conditions and the possible advantages of that approach. METHODS: Among 256 patients undergoing elective laparoscopic operations using conventionally pneumoperitoneal techniques from January 1994 to June 1995, twenty patients received diagnostic laparoscopy. The correlation between preoperative diagnosis, laparoscopic diagnosis and pathologic diagnosis as well as the outcome of laparoscopic diagnosis and treatment have been assessed. RESULTS: Major indications for diagnostic laparoscopy included acute abdominal pain (n = 4), chronic abdominal pain (n = 6), differentiating intraabdominal tumor (n = 4), staging known malignancy (n = 3) and evaluating intraperitoneal implantation (n = 3). Two of the four patients with acute abdominal conditions, one of the six patients with chronic abdominal pain. Four of the seven patients with undifferentiated/unstaged abdominal tumors and all of the three patients with intraperitoneal-implanted drainage tubes had no reasons for a further exploratory procedure, thus preventing the morbidity or mortality which might occur after unnecessary laparotomy. The duration of operation and hospitalization was shorter than the group without laparotomy. CONCLUSIONS: Diagnostic laparoscopy benefits patients by avoiding unnecessary surgery, avoiding unnecessary delay in diagnosis and treatment and shortening the operative and hospitalized period. However, it provides only an alternative not a substitute for traditional diagnostic procedures and will never lessen the importance of conventional laparotomy.

Abdomen, Acute↗