Immunohistochemical analyses of gastric stromal tumors in Taiwanese.

BACKGROUND AND PURPOSE: Gastrointestinal stromal tumors (GISTs), identified by the presence of CD117 (KIT), were previously classified as gastric and intestinal smooth muscle tumors prior to the availability of immunohistochemical methods. This study evaluated the percentage of GISTs previously diagnosed as gastric smooth muscle tumors in our hospital during an 11-year period. METHODS: A total of 81 surgically resected gastric smooth muscle tumor specimens from 81 patients were collected from January 1986 to December 1997. Immunohistochemical studies were performed on these tumors with antibodies of CD34, CD117, smooth muscle actin (SMA), S-100, and desmin. RESULTS: Among the 81 tumors, 74 (91.4%) were CD117-positive and were classified as GISTs. Among the 74 GISTs, CD34 was positive in 72 tumors (97.3%), SMA was positive in 12 tumors (16.2%), desmin was positive in 5 tumors (6.7%), and S-100 was positive in 4 tumors (5.4%). The 7 tumors classified as non-GISTs had the following immunohistochemical characteristics: 1 was a CD117-negative CD34-positive stromal tumor (GINST) [1/81, 1.2%]; 3 were schwannomas with strong S-100-positive characteristics (3/81, 3.7%); and 3 were smooth muscle tumors with both SMA- and desmin-positive status (3/81, 3.7%). No clear relationship between CD117 or CD34 expression and prognosis was found for these tumors. CONCLUSIONS: The majority (91.4%) of gastric tumors originally diagnosed as gastric smooth muscle tumors were GISTs, except for small groups of smooth muscle tumors and schwannomas.     

The Correlation between Methadone Dosages among Pairs of Heroin Users in Romantic Relationships and among Pairs of Heroin Users Who Are Siblings

This study explores whether an individual’s methadone dose is influenced by the level of another individual’s dose as a function of their relationship. Thirty-four subjects were recruited in this study; 16 subjects were in a partner relationship and 18 subjects were siblings. Multiple regression analysis revealed that the dose of one member of the dyad was a predictor of the dose of the other member of the dyad. Mean difference in dose was negatively associated with the correlation coefficient in sibling dyads but not partner dyads. Analysis of the dose curves showed that all partner dyads demonstrated a “collinearity pattern” or “coexistence pattern,” but a “distinct trend pattern” was only noted in sibling dyads. Our results suggest that there is a relationship between the methadone doses of members of a dyad and that this phenomenon is more remarkable in partnership dyads than sibling dyads.     

Endoscopic findings and management of dengue patients with upper gastrointestinal bleeding

There are 100 million cases of dengue infection, 500,000 cases of dengue hemorrhagic fever, and 25,000 deaths annually due to dengue worldwide. Gastrointestinal bleeding is the most common type of severe hemorrhage in dengue fever. However, there are no reports about the clinical applications of endoscopic therapy for upper gastrointestinal bleeding (UGI) in dengue patients. From June 17, 2002 to January 30, 2003, 1,156 patients with confirmed dengue virus infection were treated at Kaohsiung Chang Gung Memorial Hospital in Taiwan. We analyzed those patients who had received endoscopic therapy for UGI. The characteristic endoscopic findings, therapeutic courses, and amount of blood component transfused were collected from their charts for statistical analysis. Among the 1,156 dengue patients, 97 (8.4%) had complications of UGI bleeding during hospitalization. The endoscopic findings included hemorrhagic (and/or erosive) gastritis in 67% of the patients, gastric ulcer in 57.7%, duodenal ulcer in 26.8%, and esophageal ulcer in 3.1%. Of the 73 patients with peptic ulcer, 42 (57.5%) met the endoscopic criteria (recent hemorrhage) for endoscopic hemostasis therapy. Peptic ulcer patients with recent hemorrhage required more transfusions with packed red blood cells (P = 0.002) and fresh frozen plasma (P = 0.05) than those without recent hemorrhage. Among these 42 patients with recent hemorrhage, endoscopic injection therapy was conducted in 15 patients (group A). The other 27 patients (group B) did not receive endoscopic therapy. After endoscopy, patients in group A required more transfusions with packed red blood cells (P = 0.03) and fresh frozen plasma (P = 0.014) than did patients in group B. There were no significant differences between groups A and B in duration of hospital stay and amounts of transfused platelet concentrate after endoscopy. Medical treatment with blood transfusion is the mainstay of management of UGI bleeding in dengue patients. Patients having peptic ulcer with recent hemorrhage require more transfusions with packed red blood cells and fresh frozen plasma for management of UGI bleeding than those without recent hemorrhage. However, when peptic ulcer with recent hemorrhage is encountered during the endoscopic procedure, endoscopic injection therapy is not an effective adjuvant treatment of hemostasis in dengue patients with UGI bleeding.     

Prediction of viremia for cases of hepatitis C virus (HCV) infection using a third-generation anti-HCV enzyme immunoassay test

BACKGROUND/AIMS: Positive results for anti-hepatitis C virus (HCV) testing reveal subjects are infected by HCV, with presence of HCV RNA indicating persistent infection. In this study, we attempted to evaluate the validity of the HCV viremia using a commercially available, third-generation anti-HCV test. METHODOLOGY: Sample rate/cut-off rate (S/CO) ratios for 1,907 anti-HCV-positive tests (S/CO >1, AxSYM HCV 3.0; Abbott, IL, USA), which had been performed during the last three years, were retrospectively analyzed. Cases with S/CO values between 1 and 100 were divided into 20 groups according to S/CO range (in increments of 10) and ALT (normal or elevated). Ten random cases were obtained for each of the 20 groups. If cases in any group numbered < or =10, all were recruited. Totally, 193 cases were enrolled for HCV RNA detection (COBAS Amplicor; Roche Diagnostics, NJ, USA). RESULTS: The S/CO distribution was biphasic, with two S/CO peaks in the ranges 1-10 (10.7%) and 81-90 (24.2%). Regardless of the ALT level, all samples with S/COs < or =10 were negative for HCV RNA. Of the samples with S/CO values >10, the optimal cut-off was 40 with sensitivity and specificity for both of 81%. In conclusion, subjects with S/CO values < or =10 (10.7%) were more likely to be cases of past infection or of non-specific reaction. Most (90%, 108/120) of the subjects with S/COs >40 represent current or persistent infection. To predict viremia in subjects with S/COs between 10 and 40, 6.7% of all anti-HCV-positive subjects was invalid by a cross-sectional observation. CONCLUSIONS: Follow-up or further study is recommended. The third-generation EIA test plays a semiquantitative role for the prediction of viremia in HCV infection.     

Comparison of prevalence for paraumbilical vein patency in patients with viral and alcoholic liver cirrhosis

OBJECTIVES: The patent paraumbilical vein (PUV) is a venous collateral that is often found in patients with cirrhosis and portal hypertension. It can be effectively demonstrated by conventional ultrasonography (US). We conducted this prospective study to elucidate the prevalence and etiology of PUV patency for cirrhotic patients. METHODS: From August, 1997, to July, 1998, one of the authors (S.-N.L.) observed PUV patency for all cirrhotic patients during routine upper abdominal US examination. All cirrhotic patients diagnosed with portal hypertension were further analyzed. Portal hypertension was diagnosed by sonographic evidence of splenomegaly or ascites, or endoscopic varices. Cases presenting with hepatocellular carcinoma and sonographic evidence of prehepatic portal hypertension were excluded. Once a PUV patency with a diameter of > or = 3 mm was suspected based on conventional US, it was confirmed by color Doppler US. Of the 493 cirrhotic patients examined, 252 with portal hypertension and without hepatoma were enrolled in this study. RESULTS: Significant PUV patency was detected in 11.1% of the enrolled patients (28 of 252). With univariate analysis, a significantly higher prevalence was demonstrated for alcoholic patients (p < 0.0001), whereas prevalence was relatively low for those with chronic hepatitis B or C infection (p = 0.0159). A trend toward increased prevalence was noted with Child-Pugh classification (p = 0.001). Furthermore, a higher prevalence was noted in younger cirrhotic patients (p = 0.0037). Alcoholism was still a significant factor despite adjustment of Child-Pugh classification using multiple logistic regression, (OR = 3.88, 95% CI = 1.34-8.55). CONCLUSION: A significantly higher prevalence of PUV patency was demonstrated for patients with alcohol-induced liver cirrhosis in comparison to those with postviral cirrhosis.     

Gallbladder compression sign: An indicator of small isoechoic hepatic tumors

A small isoechoic liver mass is difficult to detect with ultrasound. Gallbladder compression indicates the presence of the lesion. To assess the clinical significance of the gallbladder compression (GBC) sign, we report on 9 cases of small isoechoic hepatic masses (less than 3 cm in diameter) detected by the GBC sign. The final diagnoses of these small hepatic masses was 3 hepatomas, 2 hemangiomas, 2 nodular regenerations, 1 liver abscess, and 1 normal liver lobule. The gallbladder compression sign was not seen in 4992 normal volunteers. In conclusion, the GBC sign is an useful guide for the detection of a small isoechoic mass in the liver, but the nature of the mass cannot be determined. © 1996 John Wiley & Sons, Inc.     

Comparison of clinical outcome between patients continuing and discontinuing lamivudine therapy after biochemical breakthrough of YMDD mutants

BACKGROUND/AIMS: The aim of this study was to compare the clinical outcome between patients continuing and discontinuing lamivudine therapy after the biochemical breakthrough of hepatitis B virus tyrosine-methionine-aspartate-aspartate (YMDD) mutant. METHODS: YMDD mutants were detected in 51 chronic hepatitis B patients who experienced a flare-up of alanine aminotransferase (ALT) during lamivudine treatment. Twenty-seven of them discontinued lamivudine therapy (group A), and 24 continued therapy (group B) after biochemical breakthrough. The follow-up period was 12 months in both the groups. RESULTS: There was no significant difference between groups A and B in the incidence and severity of ALT peaks and hepatic decompensation within the first 3 months after biochemical breakthrough. After the fourth month of biochemical breakthrough, however, group A experienced acute exacerbation more frequently [20/26 (77%) vs. 7/23 (30%); P=0.002] and higher ALT peaks than group B. The same result was found when the patients were divided into na?ve and retreated or cirrhotic and non-cirrhotic groups. Hepatic decompensation at the onset of biochemical breakthrough was associated with higher mortality (OR=70, 95% CI=6.06-807.75). CONCLUSIONS: Patients who discontinued lamivudine therapy increased the frequency of flare-ups and higher ALT peaks than those who continued therapy after 4 months post-breakthrough.     

Expression and prognostic role of tumor suppressor gene PTEN/MMAC1/TEP1 in hepatocellular carcinoma

BACKGROUND: Inactivation of the tumor suppressor gene PTEN/MMAC1/TEP1, located on chromosome 10q23, is a common event in advanced stages of diverse human malignancies. However, the prognostic role of PTEN expression in patients with hepatocellular carcinoma (HCC) has not been characterized. METHODS: One hundred five resected specimens were collected from patients with HCC. Expression levels of PTEN and p53 in clinical samples were analyzed by immunohistochemistry. RESULTS: Immunohistochemical analysis of 105 HCC tissue specimens revealed that decreased or absence of PTEN immunostaining was found in 43 specimens (40.9%). Reduced PTEN expression levels were correlated with increased tumor grade (P = 0.017), advanced disease stage (P = 0.016), and elevated serum alpha-fetoprotein (alphaFP) levels (P = 0.001). Kaplan-Meier analysis indicated that patients with reduced PTEN levels had shorter overall survival (P = 0.001) and higher recurrence rates (P = 0.0007) compared with patients who had intact PTEN expression. Examining p53 expression unveiled an inverse correlation between p53 overexpression and reduced PTEN expression in patients with HCC (P = 0.004). In addition, patients with p53 overexpression had shorter overall survival compared with patients who were without p53 overexpression (P = 0.0014). Univariate and multivariate analyses revealed that reduced PTEN expression was an independent prognostic factor for survival in patients with HCC. CONCLUSIONS: The current study demonstrated that reduced PTEN expression levels are involved in the pathogenesis of HCC. Moreover, decreased PTEN expression was correlated with tumor progression, high alphaFP levels, p53 overexpression, and poor prognosis in patients with HCC.