Biomedical subjects

J W Joh

Publications and source records attributed to J W Joh.

At least 19 recordsLinked to original sources

PubMed2006

Primary malignant retroperitoneal tumors: analysis of a single institutional experience.

AIMS: In order to achieve complete resection in the surgical management of retroperitoneal tumors, it is crucial to know the tumor's anatomical location relative to neighboring organs. METHODS: Forty-nine patients with primary malignant retroperitoneal tumors were divided by tumor location into two groups [upper abdomen (group 1) or lower abdomen (group 2)], and clinicopathological features, tumor recurrence, and patient survival were assessed. RESULTS: No significant differences in preoperative clinical characteristics existed between two groups, and liposarcoma was the most frequently observed tumor type. The difference in the rates of complete resection between the two groups was not statistically significant (75.9% for group 1 and 85% for group 2). En-bloc combined resection was performed in 52% and 30% of patients in groups 1 and 2, respectively. The local recurrence rate in group 2 (31.3%) was higher than that in group 1 (9.5%), despite the fact that the differences in rates of complete resection and distant recurrence rates (14.3% in group 1 and 12.5% in group 2) between the two groups were not statistically significant. The overall 5-year survival rates were 67.9% for group 1 and 43.2% for group 2 (p=0.038). The 5-year survival rate of patients with tumors smaller than 10 cm was 78.4%, while that of patients with tumors larger than 10 cm was 38.1% (p=0.017). The 5-year survival rate after complete excision was 61%, whereas that after incomplete resection or biopsy only was 40.0% (p<0.0001). CONCLUSIONS: An upper abdominal tumor location is a positive prognostic factor even if small tumor size (<10 cm) and complete resection of the tumor are still more important factors to improve outcome in patients with malignant primary retroperitoneal tumors. Because complete resection was shown to be the most important prognostic factor, an aggressive and careful surgical approach is recommended for the treatment of such tumors.

Adolescent↗

PubMed2006

Outcome of patients with recurrent hepatocellular carcinoma in liver transplantation.

Liver transplantation (OLT) is the treatment of choice for patients with hepatic cirrhosis related hepatocellular carcinoma (HCC). Among 156 liver transplant patients for HCC from June 1996 to February 2005, 23 had recurrent HCC. To evaluate risk factors that affect early recurrence of HCC after OLT, we divided the 23 patients into two groups: early (< or =12 months) and late (>12 months) recurrences. Among them, 15 patients were dead and eight alive patients had been followed to 31 July 2005. The most common recurrence site was the grafted liver (n = 15), next was bone (n = 11), lung (n = 8), lymph node (n = 6), brain (n = 4), skin (n = 2), adrenal gland (n = 1). There were no significant differences between the two groups in age or tumor size, number of tumors, cell differentiation, alpha-feto protein levels, tumor staging, number of patients within Milan criteria, steroid pulse therapy, infectious diseases, and immunostaining of tumor. In our study, there were no risk factors that predict early tumor recurrence. We noticed that more patients in the early recurrence group were excluded by Milan criteria due to a more progressed tumor staging with higher mean levels of serum alpha-feto protein.

Adult↗

PubMed2006

Outcomes of hepatitis B virus recurrence after liver transplantation.

The introduction of high doses of hepatitis B immune globulin (HBIG) and lamivudine for liver transplantation (OLT) prophylaxis has reduced the risk of hepatitis B recurrence and improved the survival of patients transplanted for hepatitis B virus (HBV)-related liver disease. But, posttransplant prophylaxis strategies to treat the recurrence of HBV have not yet been standardized. We analyzed 23 patients with HBV recurrence among 340 HBV-associated liver transplants performed from September 1996 to April 2004 (6.7%). Nine patients underwent deceased donor OLT and 14, living donor OLT. Mean follow-up was 37 months. Seroconversion after recurrence was observed in 6 of 23 patients (26%). Mean time to HBV recurrence tended to be shorter among the seroconversion (+) patients compared to seroconversion (-) patients (10 months vs 19.7 months; P = .062). Seroconversion rate after HBIG and lamivudine combination therapy for patients with HBV recurrence was 37.5% and time to seroconversion after HBV recurrence was 1.7 months. Seroconversion was best achieved when the pretransplant HBV DNA level was high and HBeAg was positive. Also, seroconversion rate was increased when HBV DNA level was low and the alanine transferase level high at the time of recurrence and when the time to recurrence after transplantation was short. Seroconversion after HBV recurrence, which was observed in 26%, may be increased in selected cases. Accordingly, aggressive treatment should be undertaken after HBV recurrence.

Antiviral Agents↗

PubMed2006

Liver transplantation for hepatocellular carcinoma with bile duct thrombi.

In a few cases of hepatocellular carcinoma (HCC), jaundice results from obstructive causes, including tumor invasion or thrombi in the bile duct. We have reported herein our experience with liver transplantation (OLT) for HCC cares showing bile duct thrombi (BDT). From September 1996 to August 2004, 140 adult patients underwent OLT for HCC at our center. Four patients (2.9%) who had OLT performed for HCC had BDT and were included in this study. The patients were all men of mean age 57.0 years. The initial total bilirubin levels were in the range of 2.0 to 30.5 mg/dL. The sizes of the tumors ranged from 2.0 cm to 3.0 cm in diameter, all were single lesions. The median follow-up period was 20.6 months (range: 17.6 to 28.1 months). The only case in which the BDT was identified intraoperatively died 20 months after OLT due to multiple intrahepatic recurrences. The other three patients were alive, showing no evidence of recurrence at the end of follow-up. Although a series of four is too small to reach any conclusion, we suggest that OLT may be a treatment option for HCC with BDT in selected cases.

Adult↗

PubMed2006

Safety of donors with fatty liver in liver transplantation.

Steatotic liver graft transplantation affect donor safety as well as recipient survival. We investigated safety of donors according to the extent of fatty change. We retrospectively reviewed donors who underwent right hepatectomy from September 1999 to April 2005, dividing them into three groups according to degree of macrovesicular fatty change upon intraoperative liver biopsy. Group 1 included patients with macrovesicular steatosis of 0 approximately 9%: group 2, 10 approximately 19% and group 3, at least 20%. Two hundred forty-five donors were enrolled with a male to female ratio of 2.02:1 and mean age of 31.8 years. There were 163 donors in group 1, 75 in group 2, and seven in group 3. There was no statistically significant difference in body mass index, operative time, blood loss, postoperative peak serum bilirubin, and aspartate transaminase levels among groups 1, 2, and 3. Overall complication rate, including reoperation, biliary stricture, wound infection, ileus, transfusion, bile leak and fluid collection were not different between the groups. Postoperative hospital stay was also not different. Peak alanine transaminase level was different between each group, and prothrombin time between group 1 and 3, but days until return to normal levels in all measured laboratory parameters were not different. Residual liver volume percent was significantly smaller among group 1 compared to others. In conclusion, fatty livers with less than 30% macrovesicular steatosis may be good donor candidates without significant complications as long as sufficient residual liver volume is left for the donor.

Adolescent↗

PubMed2005

Genotypic resistance of hepatitis B virus to lamivudine in renal transplant recipients.

Renal recipients with hepatitis B virus (HBV) should be treated with prolonged lamivudine. However, lamivudine resistance usually results after YMDD mutation within the HBV polymerase gene. Thereupon, the aim of this study was to investigate the genotypic resistance to lamivudine among renal transplant recipients to identify its effect on the clinical course of HBV in these patients. Between March 1997 and September 2003, eight of 17 renal transplant patients with hepatitis B virus were enrolled into this study and treated with 100 mg of lamivudine once each day. We amplified a selected region of the polymerase gene of HBV in order to confirm mutations in the YMDD motif. Mutations of YMDD region were observed in five of eight patients (62.5%). Out of five patients positive for HBV DNA, three (60%) showed genotypic resistance (YMDD mutation) with a normal ALT level. Two patients converted to HBV DNA negative. But, they were not associated with HBeAg seroconversion. Out of three patients who were pretransplant HBV DNA negative, genotypic resistance was observed in two patients (67%) revealing both positivity of HBe antibody and negativity of HBV DNA. In conclusion, although a normal ALT level and HBV DNA negative are maintained, the mutation of the YMDD locus may develop. Accordingly, we suggest that if the YMDD mutation is not involved in the progression of hepatitis B, lamivudine therapy should be continued despite genotypic resistance.

Adult↗

PubMed2005

Microvascular tumor embolism: independent prognostic factor after liver transplantation in hepatocellular carcinoma.

Microscopic tumor cell dissemination may be a more important factor in the recurrence of hepatocellular carcinoma (HCC) after liver transplantation, probably because of posttransplant immunosuppression. The presence of microvascular tumor embolism was undetermined as a factor for HCC recurrence after orthotopic liver transplantation (OLT). This study evaluated whether microvascular tumor embolism affects recurrence-free survival and correlates with other clinicopathologic factors after OLT among patients with HCC. From September 1996 to June 2003, 72 OLTs for HCC were enrolled in this study. Median follow-up was 22.8 months. Among 41 patients without microvascular tumor embolism, 1-year, 2-year, and 5-year recurrence-free survival rates were all 97.6%, while these rates were 77.3%, 68.2%, and 59.7%, respectively, for 31 patients (43.1%) with microvascular tumor embolism (P = .0006). The 5-year recurrence-free survival rate showed significant differences for a pT2 tumor (P = .0073), for maximal tumor size <3 cm (P = .0328), for > or =5 cm solitary tumor (P = .0095), and for the presence of a tumor capsule (P = .0012), within the Milan criteria (P = .0376). At multivariate analysis, significant independent predictors for HCC recurrence were microvascular tumor embolism and histopathologic grade. In conclusion, microvascular tumor embolism is an independent predictor of HCC recurrence after liver transplantation. Although OLT is a safe and effective treatment for HCC within the Milan criteria, the presence of microvascular tumor embolism at pathologic examination can predict its recurrence. In these cases, the feasibility of immunosuppressive therapy or adjuvant chemotherapy must be considered to prevent tumor recurrence.

Adult↗

PubMed2004

Patterns of failure in gastric carcinoma after D2 gastrectomy and chemoradiotherapy: a radiation oncologist's view.

The risk of locoregional recurrence in resected gastric adenocarcinoma is high, but the benefit of adjuvant treatment remains controversial. In particular, after extended lymph node dissection, the role of radiotherapy is questionable. Since 1995, we started a clinical protocol of adjuvant chemoradiotherapy after D2 gastrectomy and analysed the patterns of failure for 291 patients. Adjuvant chemotherapy consisted of five cycles of fluorouracil and leucovorin, and concurrent radiotherapy was given with 4500 cGy from the second cycle of chemotherapy. With a median follow-up of 48 months, 114 patients (39%) showed any type of failure, and the local and regional failures were seen in 7% (20 out of 291) and 12% (35 out of 291), respectively. When the recurrent site was analysed with respect to the radiation field, in-field recurrence was 16% and represented 35% of all recurrences. Our results suggest that adjuvant chemoradiotherapy has a potential effect on reducing locoregional recurrence. Moreover, low locoregional recurrence rates could give a clue as to which subset of patients could be helped by radiotherapy after D2 gastrectomy. However, in order to draw a conclusion on the role of adjuvant radiotherapy, a randomised study is needed.

Adenocarcinoma↗

PubMed2004

The viability and function of cryopreserved hepatocyte spheroids with different cryopreservation solutions.

We sought to evaluate the viability and function of cryopreserved hepatocyte spheroids using different cryopreservation solutions in order to elucidate the efficiency of cryopreservation. Hepatocytes isolated from a Sprague-Dawley rat were formed into spheroids by 24 hours of rotational culture. The spheroids were cryopreserved using a programmed linear freezer in a liquid nitrogen tank for 24 hours in four different cryopreservation solutions: UW solution (UW), William E media (WE), fetal bovine serum (FBS), and a mixture (MIX). After thawing, they were cultured for 4 days. With each hepatocyte spheroid, the viability using the MTT assay and hepatocyte-specific functions, such as ammonia clearance, urea nitrogen synthesis, and albumin secretion, were analyzed. The viabilities of cryopreserved hepatocyte spheroids were 64.8% +/- 10.2% (UW), 33.2% +/- 9.7% (WE), 69.3% +/- 8.7% (FBS), and 48.4% +/- 15.5% (MIX). Ammonia clearance of spheroids cyropreserved in UW solution was 0.93 +/- 0.13 mmol/L per well per day, which was not significantly different from freshly cultured spheroids. From the aspect of urea nitrogen synthesis, spheroids cryopreserved with UW, FBS, and MIX solution were not significantly different from freshly cultured spheroids. The amount of albumin secretion by the UW cryopreserved spheroids was significantly greater than that of other cryopreserved spheroids. Cryopreserved hepatocyte spheroids in UW solution were not significantly different from freshly cultured spheroids with respect to viability and function. UW solution was superior to other cryopreservation solutions for viability and functions.

Animals↗

PubMed2004

Randomized trial of tacrolimus versus cyclosporine in steroid withdrawal in living donor renal transplant recipients.

The introduction of new immunosuppressants has prompted trials of steroid withdrawal. However, several groups have reported a higher incidence of rejection. We conducted a randomized two-arm, parallel-group, open-label, prospective study to compare steroid withdrawal (at 6 months posttransplant) from the regimens of tacrolimus + mycophenolate mofetil (MMF) (FK group) versus cyclosporine + MMF (CSA group). The entry criteria were recipients of first living donor transplants with no diabetes mellitus (DM), congestive heart failure, chronic liver disease, or acute rejection within 6 months posttransplant. The primary endpoint was a biopsy-proven acute rejection episode or treatment failure within 1 year posttransplant. While 87 recipients were assigned to FK (n = 43) and CSA groups (n = 44) before transplantation, 76 recipients (FK 39, CSA 37) could be tapered off steroids at 6 months posttransplant, since 11 were excluded due to acute rejection within 6 months posttransplant (FK two, CSA three) or protocol violations (FK two, CSA four). After steroid withdrawal, the incidence of acute rejection episodes was 0% in the FK group and 13.5% in the CSA group (P < .05). Other results at 12 months posttransplantation were comparable: the incidences of DM 7.8% versus 0% (FK group vs CSA group), hypercholesterolemia 41.0% versus 59.5%, hypertensives 48.7% versus 59.6% as well as the levels of plasma creatinine 1.21 +/- 0.24 versus 1.31 +/- 0.50 mg/dL (P > .05 in every variable). These data suggest that steroid withdrawal is successful in first living donor renal transplant recipients. Tacrolimus may be significantly more effective than cyclosporine to prevent acute rejection after steroid withdrawal.

Adrenal Cortex Hormones↗

PubMed2004

Prognostic factors affecting graft and patient survival in cadaveric and living kidney transplantation.

Numerous studies have reported various prognostic factors that affect graft and patient survival in living and cadaveric donor kidney transplantation (KT). The purpose of this study was to evaluate the clinical outcomes and prognostic factors affecting graft and patient survivals in living and cadaveric donor KT. Between February 1995 and December 2001, 421 patients who had undergone cadaveric donor KT (group I: 216 cases, 51.3%) or living donor KT (group II: 205 cases, 48.7%), were retrospectively analyzed. Five-year overall graft survival rates in living was significantly better than that in cadaveric donor KT, respectively (P = .0234). There was no difference in patient survival rates between the two groups. Such factors as absence of rejection, female donor, female recipient, adult KT according to recipient age (>14 years), and donor serum creatinine level just before transplantation (< 2.5 mg/dL) were significantly associated with good graft survival among cadaveric donor KT, whereas two factors-absence of rejection and adult KT according to recipient age (>14 years)-influenced graft survival in living donor KT. In multivariate analysis, the only significant prognostic factor related to graft survival was the presence of rejection. In conclusion, we suggest that the presence of rejection is the only factor that impairs graft survival in both cadaveric and living donor KT, while other factors affected graft survival differently in the two groups.

Adult↗

PubMed2004

Auxiliary partial orthotopic liver transplantation in the treatment of acute liver failure: a case report.

A successful experience with auxiliary partial orthotopic liver transplantation (APOLT) for acute liver failure is reported in a 29-year-old woman who experienced jaundice, generalized erythema for 7 days, and decreased mentation for 3 days. Two months prior, she suffered pulmonary tuberculosis, being currently treated with antituberculous medications, which caused the fulminant hepatic failure. We decided to perform APOLT based on two facts. The first was the possibility that the diseased native liver may recover sufficiently to withdraw the immunosuppressants. Second, the pulmonary tuberculosis may have been worsened by immunosuppression. We removed the extended lateral section of the recipient for the graft. The left hepatic vein of the extended left lateral graft was anastomosed to the left hepatic vein of the recipient. The left portal vein of the graft was anastomosed to the left portal vein of the recipient. The right portal vein of the recipient was left without any manipulation. A duct-to-duct anastomosis was performed. On postoperative day 3, antituberculous medications were started. On the postoperative day 37, she was discharged without any problems. On the postoperative day 120, she showed no event of rejection, and her pulmonary symptoms improved. We performed the operation without transection of the portal branch to the native liver, but no functional competition has been discovered.

Adult↗

PubMed2004

Factors affecting graft survival after living donor liver transplantation.

Living donor liver transplantation (LDLT) has been considered as an alternative option to resolve the shortage of cadaveric donor organs, despite the ethical aspects of the donor procedure. The objective of this study was to analyze the risk factors affecting graft survival in LDLT. From June 1996 to December 2002, 141 patients who underwent LDLT were retrospectively analyzed. Graft survival rates were 82.5%, 80%, 77.3%, and 77.3% at 6 months, 1 year, 3 years, and 5 years, respectively. The factors influencing graft survival in univariate analysis were graft-to-recipient body weight ratio (GRWR) less than 0.8% (P = .0009), intraoperative transfusion of more than six packed RBC units in addition to the use of cell saver amounts (P = .0001), left lobe grafts in adults causing small-for-size situations (P = .0135), and donor age (P = .0472). The multivariate analysis demonstrated that GRWR less than 0.8% (P = .002) and intraoperative transfusion of more than six packed RBC units (P = .014) were independent factors that decreased graft survival rates. The graft selection of greater than 0.8% of GRWR and reduction of intraoperative RBC transfusion improve graft survival.

Adolescent↗

PubMed2004

Clinicopathological features of incidental hepatocellular carcinoma in liver transplantation.

The incidence of detecting hepatocellular carcinoma (HCC) in a removed recipient liver after a liver transplant is not rare. The clinical features are expected to be different from the preoperatively diagnosed HCC. The aim of this study was to evaluate the clinicopathological features of incidental HCC. This study retrospectively analyzed five cases of incidental HCC among 51 liver transplant cases of HCC operated from September 1996 to February 2002. The proportion of an incidental HCC was 9.8%. The mean age was 46.2 years with a higher prevalence in may (80%, four cases). The alpha-fetoprotein level was normal or mildly elevated. HBsAg was positive in all cases. Imaging studies revealed regenerative or dysplastic nodules, or no specific lesion. The pathological findings demonstrated a mean size of 1.16 cm, multiplicity in three cases (60%), no microvascular invasion, and Edmonson grade I (60%) and II (40%). There was no recurrence of the HCC. However, two patients died due to an intracranial hemorrhage and a graft failure, respectively. In conclusion, incidentally found HCC showed less invasive pathological features and a better prognosis.

Carcinoma, Hepatocellular↗

PubMed2004

A case of laryngeal posttransplantation lymphoproliferative disease.

The development of posttransplant lymphoproliferative disease (PTLD) is strongly linked to infection with the Epstein-Barr virus (EBV), immunosuppression-state, the type of allograft, and EBV-seronegativity. A 18-month-old girl who had undergone living donor liver transplantation using the left lateral segment from her father was treated with tacrolimus and corticosteroid as an immunosuppressant regimen. She was readmitted 3 months after the transplant to evaluate the etiology of dyspnea and abdominal fullness as well as a decreased urine volume. She was diagnosed as an anastomotic stenosis of the hepatic vein for which she underwent balloon angioplasty. The treatment was repeated at postoperative month 5, 8, and 11. As postoperative 6 months, the result of the serological EBV-CA (IgG/IgM) was positive. In postoperative month 10, the EBV PCR serologic test become positive, and a laryngeal biopsy revealed PTLD. She was treated with acyclovir and gangyclovir as well as reduced immunosuppression. We report herein a rare case of laryngeal PTLD in a patient who had undergone living donor liver transplant with paternal allograft.

Female↗

PubMed2004

Sustained release of vascular endothelial growth factor from calcium-induced alginate hydrogels reinforced by heparin and chitosan.

A possible alternative for immunosuppression is a microencapsulation technique using hydrogels, which have been utilized for cell immobilization and drug delivery systems. Angiogenesis is crucial for delivery of the metabolic products to the host tissues as well as to supply oxygen and nutrients to cells. The local delivery of angiogenic growth factors, such as VEGF and basic FGF, has been recently studied to enhance angiogenesis on peripheral tissue of graft. In this study, we evaluated sustained VEGF release with a model using hydrogels coated with chitosan and heparin in vitro. We fabricated calcium alginate gels and chitosan-coated calcium alginate gels. Heparinized chitosan-coated calcium-induced alginate hydrogel beads were prepared by soaking chitosan-coated calcium alginate gels in heparin solution. We compared the stability and VEGF release manner between three kinds of hydrogels. To compare the stability, 5 mL of each hydrogel was incubated with 20 mL PBS under the rotational culture. Compression forces were measured using a rheometer. The amount of VEGF released from the gels was measured by ELISA. The heparin-coated chitosan alginate hydrogels showed the highest surface stability among the three hydrogels. VEGF from the heparinized gel was released in sustained manner up to 10 days in vitro. Chitosan-coated alginate gels released 90% of loaded VEGF within 5 days. These results suggest that local delivery of VEGF using a heparinized hydrogel may provide a long-term supply of angiogenic growth factor that might induce new vessel formation in vivo.

Alginates↗

PubMed2004

Interpostion vein graft in living donor liver transplantation.

UNLABELLED: In adult-to-adult living donor liver transplantation (LDLT), right lobe grafts without a middle hepatic vein can cause hepatic congestion and disturbance of venous drainage. To solve this problem, various types of interposition vein graft have been used. OBJECTIVES: We used various types of interposition vein grafts for drainage of the paramedian portion of the right lobe in living donor liver transplantation. METHODS: From June 1996 to June 2003, 37 of 176 patients (128 adults, 48 pediatric) who underwent LDLT received vein grafts for drainage of segments V, VIII, or the inferior portion of the right lobe. RESULTS: In 36 adult cases the reconstruction included the inferior mesenteric vein of the donor (n = 14); cadaveric iliac vein stored at cold (4 degrees C) temperature (n = 5); cryopreserved (-180 degrees C) cadaveric iliac vein (n = 10); cryopreserved cadaveric iliac artery (n = 1 case); donor ovarian vein (n = 1); recipient umbilical vein (n = 3); recipient saphenous vein (n = 1); recipient left portal vein (n = 1); recipient left hepatic vein (n = 1). In a pediatric case with malignant hemangioendothelioma that encased and compressed the inferior vena cava, we used an interposition vein graft to replace the inferior vena cava. CONCLUSION: Various types of interposition vein grafts can be used in living donor liver transplantation. Cryopreserved cadaveric iliac vein and artery are useful to solve these drainage problems.

Adult↗

PubMed2004

Case of living donor liver transplantation in a patient with biliary atresia combined with situs inversus.

Until recently, situs inversus was considered to be an absolute contraindication for liver transplantation. However, recent reports have suggested that situs inversus should not be considered a contraindication. This study presents a successful living donor liver transplantation performed in a 4-month-old male infant with biliary atresia and situs inversus. The surgical findings revealed abdominal situs inversus with polysplenia and an absent retrohepatic inferior vena cava and intestinal malrotation.

Adult↗