Disseminated cystic lymphangiomatosis presenting with acute abdomen: report of a case and review of the literature

Lymphangioma is an uncommon tumor. Lymphangiomatosis, a benign tumor consisting of a cluster of dilated lymphatic channels, is very unusual. Most lymphangiomatoses are found in the neck and head area. Less than 5% are diagnosed intraabdominally and they are very infrequently encountered in the retroperitoneal area. Herein, we report a rare case of a 32 year-old woman who had disseminated intra-abdominal and retroperitoneal cystic lymphangiomatosis, which presented as acute abdomen. She received exploratory laparotomy due to the suspicion of malignancy, which was finally confirmed as cystic lymphangiomatosis. The clinical manifestations, imaging features, and management of this patient are discussed and compared with previous literature.

Endoscopic diagnosis of intestinal metaplasia of stomach--accuracy judged by histology

BACKGROUND/AIMS

To testify proposed endoscopic criteria in surveying intestinal metaplasia (IM), we conducted a prospective study to assess the accuracy of endoscopic diagnosis of IM correlated with histology.

METHODOLOGY

Between January 1996 and July 1997, 87 subjects undergoing endoscopic examination as part of a health check-up were enrolled. Subjects whose endoscopic features showed whitish color change with plaques, patches or homogeneous discoloration on gastric mucosa were diagnosed as IM and enrolled in group A, while subjects without any of these endoscopic features were enrolled in group B. Endoscopic biopsies were taken from areas with whitish changes and normal-looking mucosae for histological correlation.

RESULTS

There were 8 subjects with whitish plaques, 29 subjects with whitish patches, and 8 subjects with homogeneous whitish discoloration enrolled in group A. In contrast, 42 subjects without any endoscopic features of IM were enrolled in group B. After verification by endoscopic biopsy with histologic examination, 30 and 10 subjects were histologically confirmed to have IM in groups A and B, respectively. The overall sensitivity, specificity, positive predictive value, negative predictive value, and accuracy of endoscopic diagnosis was 75%, 68.1%, 66.7%, 76.2%, and 71.3%, respectively. There was a positive relationship between age and sensitivity, and tendency of an inverse relationship between age and specificity.

CONCLUSIONS

The proposed endoscopic criteria are valuable in detecting three-fourths of IM patients during routine endoscopic examination. It was more effective to detect IM in elderly patients and to exclude IM in younger subjects by these criteria.

Helicobacter pylori stool antigen (HpSA) test--a simple, accurate and non-invasive test for detection of Helicobacter pylori infection

BACKGROUND/AIMS

To access the reliability of a newly developed test, the Helicobacter pylori (H. pylori) stool antigen (HpSA) test was used for detection of H. pylori infection.

METHODOLOGY

Stool specimens were collected from 33 consecutive patients (19 males and 14 females, age range: 16-73 years, mean: 49 years) who received upper gastrointestinal endoscopic examination for gastrointestinal symptoms. The H. pylori status was evaluated based on six different tests: culture, histology, biopsy urease test, 13C-urea breath test (13C-UBT), serology, and HpSA test. A commercial kit using an enzyme-linked immunosorbent assay examined HpSA in the stool. H. pylori status was defined as positive when the culture was positive or concordance of three of the other four tests (histology, biopsy urease test, 13C-UBT, and serology) was positive.

RESULTS

Twenty patients were diagnosed as H. pylori-positive. The HpSA test was positive in 19 patients and negative in 14 patients. The sensitivity and specificity were 95.0% and 100%, respectively. The overall accuracy rate was 96.3%.

CONCLUSIONS

The HpSA test is a new, simple, non-invasive method for accurate diagnosis of H. pylori infection.

Overexpression of p53 is not associated with drug resistance of gastric cancers to 5-fluorouracil-based systemic chemotherapy

BACKGROUND/AIMS

Recent in vitro evidence has strongly suggested that most anti-cancer drugs exert their cytotoxic effects via a p53-dependent apoptosis pathway. An intact p53 molecule appears to be a prerequisite for the cancer cells to be susceptible to these drugs. In this study, we specifically examined if overexpression of p53 may confer drug resistance on human gastric cancer.

METHODOLOGY

All patients were treated by an empirical HDFL regimen (weekly 24-hour infusion of 5-FU, 2,600 mg/m2 and leucovorin, 300 mg/m2) in a prospective phase II clinical trial. Among them, patients with adequate pre-chemotherapy gastric cancer tissues for immunohistochemical studies were selected for this study. A p53 DO7 monoclonal antibody was used to detect the overexpression of p53. The results were designated as "-" or "+" by the independent interpretation of two pathologists.

RESULTS

A total of 30 patients, 18 men and 12 women, with a median age of 61.5 years (range: 32-78 years), were studied. There were 15 responders and 15 non-responders to HDFL chemotherapy. The percentage of p53 overexpression with positive DO7 staining was 20.0% (6 out of 30). There were no significant differences in the pertinent clinicopathologic features between the patients with positive staining of p53 and the patients with negative staining of p53. Three out of 6 (50.0%) patients with positive staining of p53 and 12 out of 24 (50.0%) patients with negative staining of p53 responded to chemotherapy, respectively (p = 1.000 by Fisher's exact test).

CONCLUSIONS

Our data suggested that the overexpression of p53 does not predict drug resistance to 5-FU of human gastric cancer.

Timing and necessity of endoscopy in AIDS patients with dysphagia or odynophagia

BACKGROUND/AIMS

Dysphagia and odynophagia are common problems with significant morbidity in acquired immunodeficiency syndrome (AIDS) patients. Endoscopy in AIDS patients with esophageal symptoms is valuable for diagnosis, but the timing and necessity of routine endoscopy remains controversial.

METHODOLOGY

We retrospectively studied 40 AIDS patients undergoing upper gastrointestinal endoscopy. Among them, 25 patients were enroled with dysphagia and/or odynophagia and were put on empirical fluconazole treatment before endoscopic evaluation.

RESULTS

Fourteen (56%) of 25 patients improved after fluconazole treatment, while 11 patients had persistent symptoms. Among the 14 patients with symptomatic improvement, 7 were found to have esophageal candidiasis which improved after continuation of fluconazole for 1-2 more weeks. The other 7 patients had a normal endoscopic appearance. In contrast, among 11 patients with persistent symptoms, there were 3 patients with azole-resistant candidiasis, 3 with cytomegalovirus esophagitis, 1 with herpes simplex virus esophagitis with candidiasis, 1 with Kaposi's sarcoma, and 3 with idiopathic esophageal ulcer. They were successfully treated with Amphotericin B, Ganciclovir, Acyclovior, and oral steroids, except for the patient with Kaposi's sarcoma.

CONCLUSIONS

Routine endoscopy may not necessarily be indicated in every AIDS patient with dysphagia or odynophagia. Empirical fluconazole treatment can improve symptoms in 50% of patients. It is only indicated when patients have persistent symptoms after empirical treatment. With endoscopic examination, etiologic agents other than common candidiasis can be determined and the patients can thus be put on specific treatment.

Helicobacter pylori-seronegative gastric carcinoma: a subset of gastric carcinoma with distinct clinicopathologic features

BACKGROUND/AIMS

The frequent association of gastric atrophy and intestinal metaplasia in gastric cancer (GC) might preclude serologic detection of Helicobacter pylori (H. pylori) infection in GC. By using polymerase chain reaction (PCR) for detection, we would like to determine whether there exists a subset of genuinely H. pylori-negative GC patients, and whether they have distinct clinicopathologic features or not.

METHODOLOGY

IgG antibodies against H. pylori were determined by ELISA in sera, and H. pylori DNA was detected by PCR in resected gastric specimens from 160 GC patients. Clinicopathologic characteristics were then compared among group A: seropositive, group B: seronegative but PCR-positive, and group C: seronegative and PCR-negative.

RESULTS

Among 160 patients, 105 (65.6%) were classified as group A, 25 (15.6%) as group B, and 30 (18.8%) as group C. Group B patients were older and had more infiltrative tumor growth than group A. Group C had a significantly higher frequency of female predominance, and their cancers were of a more cardiac location and of the diffuse histologic subtype than those of groups A and B.

CONCLUSIONS

A significant portion (15.6%) was negative to ELISA but positive to PCR, suggesting that older ages and infiltrative tumor growth might preclude serologic detection of H. pylori infection by impairing humoral responses. Although the majority (81.2%) has a strong association with H. pylori infection, an H. pylori-negative subset indeed exists and has distinct clinicopathologic features, supporting that causes other than H. pylori infection are involved in GC carcinogenesis.

Anomalous pancreaticobiliary ductal union--an etiologic association of gallbladder cancer and adenomyomatosis

BACKGROUND/AIMS

Anomalous pancreaticobiliary ductal union (APBDU) has been proposed as a risk factor of gallbladder cancer. To clarify the frequency and the subtype distribution of APBDU in patients with gallbladder cancer and adenomyomatosis, a retrospective study was performed.

METHODOLOGY

The radiograms of endoscopic retrograde cholangiopancreaticography of 680 patients with well-documented biliary and pancreatic ducts from April 1992 to November 1996 were reviewed. The length of the common channel and insertion of the pancreatic duct and the bile duct were identified and recorded.

RESULTS

Gallbladder cancer and adenomyomatosis were identified in 8 and 12 patients, respectively. Patients with gallbladder cancer were significantly older (mean age: 66.5 years, p<0.01) than those with gallbladder adenomyomatosis (mean age: 42.7 years). APBDU was noted in 59 (8.7%) of 680 cases with complete pancreaticobiliary radiograms. Among them, 5 of 8 patients with gallbladder cancer coexisted with APBDU. Four (80%) belonged to the P-B type. Six of 12 patients with gallbladder adenomyomatosis had APBDU. Five (83.3%) belonged to P-B type.

CONCLUSIONS

Patients with gallbladder cancer and adenomyomatosis were frequently associated with APBDU. The close relationship and similar distribution of the P-B type of APBDU in both diseases suggest an etiologic association in various gallbladder diseases.

Gastric leiomyosarcoma mimicking a cystic tumor at the pancreatic tail--one case report

A 73 year-old female patient suffered from anemia and a palpable abdominal mass. Abdominal ultrasonography and magnetic resonance imaging revealed a lesion with papillary excrescences at the pancreatic tail. Endoscopic retrograde cholangiopancreatography showed a normal pancreatic duct, but a small submucosal tumor was found in the stomach incidentally. Laparotomy disclosed an exophytic tumor arising from the submucosal layer of the stomach. Pathology revealed a gastric leiomyosarcoma with remarkable liquefaction and cystic change. Gastric leiomyosarcoma can be so necrotic as to be mistaken for a cystic tumor. It is critically important to differentiate the peripancreatic cystic lesion because the treatment strategy is totally different.

Helicobacter pylori infection and age on the development of intestinal metaplasia--a multiple logistic regression analysis

BACKGROUND/AIMS

Both intestinal metaplasia (IM) and Helicobacter pylori (H. pylori) infection have been linked to gastric carcinogenesis in an age-dependent manner. However, their relationship remains ill defined, especially with respect to age.

METHODOLOGY

Three hundred and two asymptomatic subjects (167 males and 135 females; mean age 44.3+/-11.1 years) underwent complete endoscopic examination and biopsy at the antrum and the corpus. H. pylori infection was diagnosed according to histopathology and serology, while IM was determined by histopathology.

RESULTS

Eighty-four patients (27.8%) had IM, while 185 patients (61.3%) were seropositive to H. pylori. The frequency of IM was higher in patients with gastric ulcer (9/14, 64.3%) than in those with minimal change (68/229, 29.7%) or duodenal ulcer (7/59, 11.9%), both p<0.01. Patients with IM had a higher mean age (49.5+/-14.1 vs. 42.3+/-9.0, p<0.01) and a higher H. pylori prevalence than those without IM (61/84, 72.6% vs. 124/218, 56.9%, p<0.01). The concordance rate of H. pylori infection between histopathologic and serologic diagnosis was lower in patients with IM (67/84, 79.8%) than those without (196/218, 89.9%, p<0.05). Using logistic regression analyses, the development of IM was noted to be independently related to both H. pylori infection (odds ratio=1.97, 95% confidence interval: 1.1(3.53)) and age (odds ratio = 1.93, 95% confidence interval: 1.51(2.47)).

CONCLUSIONS

These data suggest that age and H. pylori infection are independent risk factors for the development of IM. Furthermore, H. pylori infection may have been underestimated in patients with IM because of the use of a single method of detection.

Overexpression of p53 in different subtypes of intestinal metaplasia and gastric cancer

p53 immunostaining was evaluated in cancerous epithelia and adjacent intestinal metaplasia of 135 gastric cancer specimens. The differential p53 overexpression in different subtypes of intestinal metaplasia and gastric cancer suggests that type III intestinal metaplasia is the commonest lesion in dysplasia-carcinoma transition, particularly in the intestinal type of gastric cancer.

High-level expression of Na+/D-glucose cotransporter (SGLT1) in a stably transfected Chinese hamster ovary cell line

The coding region of the high affinity Na+/d-glucose cotransporter (SGLT1) was inserted into the eukaryotic expression vector GFP-N1 under the control of a CMV promoter. The plasmid was then stably transfected into a Chinese hamster ovary cell line (CHO). Transcription and synthesis of SGLT1 were proved by Northern and Western blot analyses. Transport activities of the transfected cells (G6D3) were examined by measuring the sodium-dependent uptake of alpha-methyl[14C]d-glucoside (AMG). Kinetic analysis revealed a Vmax of 10.3 nmol/min/mg (total cell protein) and a Km of 0.26+/-0.09 mM, respectively. The concentration of phlorizin required to inhibit AMG uptake by 50% in the presence of 0.1 mM AMG was 2.35+/-1.84 microM. Electrophysiological studies showed that AMG induces a significant depolarization of membrane voltage in stably transfected CHO cells, suggesting an electrogenic Na-AMG symport. Immunoprecipitation with an antipeptide antibody yielded a nearly homogeneous polypeptide with a molecular mass of about 72 kDa. The amount of SGLT1 present in the CHO cell plasma membranes represents at least 1% of membrane protein, which is about 30-100 times higher than in natural sources, such as renal brush border membranes. In conclusion, the stably transfected G6D3 cells with a markedly high SGLT1 expression can serve as a promising model for studying cellular events related to Na+/d-glucose cotransport and for analyzing the structure and function of the cotransporter itself.

Optimized conditions for growth and fermentation of Helicobacter pylori

This study attempted to optimize the growth conditions of Helicobacter pylori by comparing the growth of H. pylori in an anaerobic jar and an incubator. It was found that the primary isolation rate of H. pylori from gastric biopsies was higher in an anaerobic incubator (28/30) than in an anaerobic jar (21/30). In addition, growth rate in the subsequent passage was also higher in an incubator. By comparing different supplements in the liquid media, it was found that most strains grew best in Brucella broth containing 5% fetal calf serum, and some strains grew well with the supplement of 0.2% of beta-cyclodextrin. A large scale culture using a bioreactor indicated that a defoaming agent, polypropylenglycol, profoundly inhibited the growth of H. pylori. However, fermentation could be successfully performed by continuously infusing mixed airs composed of 5% O2, 10% CO2 and 85% N2. Moreover, the production of secreted proteins of H. pylori strains grown in the bioreactor was the same as that in an anaerobic jar. Results presented herein can be used to further optimize conditions for enhancing the growth of H. pylori.

Pancreaticobiliary diseases associated with anomalous pancreaticobiliary ductal union

BACKGROUND

Anomalous pancreaticobiliary ductal union (APBDU) is associated with different pancreaticobiliary diseases. The aim of this study is to clarify the frequency with which it occurs and its several subtypes in various pancreaticobiliary diseases.

METHODS

Radiograms of 1752 subjects who underwent endoscopic retrograde cholangiopancreatography were reviewed independently by two endoscopists. APBDU was diagnosed using recently accepted criteria and divided into B-P and P-B subtypes according to the insertion of biliary and pancreatic ducts.

RESULTS

Fifty-nine (8.7%) of 680 subjects with clearly visualized pancreaticobiliary radiograms had APBDU. APBDU was present in 93.8% of patients (15 of 16) with choledochal cyst, 62.5% (5 of 8) with gallbladder cancer, 33.3% (9 of 27) with common bile duct cancer, 50.0% (6 of 12) with gallbladder adenomyomatosis, 13.2% (7 of 53) with biliary pancreatitis, 3.4% (10 of 293) with cholelithiasis, 2.2% (2 of 89) with non-biliary pancreatitis, 2.1% (1 of 47) with hilar cholangiocarcinoma, 1.9% (1 of 54) with pancreatic cancer, and 10.2% (9 of 88) with other miscellaneous disorders. There were 25 patients (42.4%) with the B-P type and 34 patients (57.6%) with the P-B type of APBDU. Patients with choledochal cyst frequently had the B-P type, whereas gallbladder cancer, adenomyomatosis, or biliary pancreatitis frequently coexisted with the P-B type.

CONCLUSION

APBDU is relatively common in patients undergoing endoscopic retrograde cholangiopancreatography at our center. There are a variety of pancreaticobiliary diseases that are associated with APBDU. Its role in these conditions is uncertain and needs to be further delineated.

Molecular mechanisms of clarithromycin resistance in Helicobacter pylori

Combination antibiotic therapy for Helicobacter pylori has now become the standard means of treating peptic ulcer diseases. Clarithromycin is a newly adopted antibiotic for H. pylori eradication. However, resistance to clarithromycin reduces the efficacy of clarithromycin-containing regimens. We explored mechanisms of clarithromycin resistance by evaluating H. pylori for macrolide resistance mechanisms reported in H. pylori and other bacteria. Degenerate polymerase chain reaction analysis of the H. pylori genome failed to yield products homologous to methylase, a drug inactivation enzyme, or efflux pumps. Clarithromycin selection in Escherichia coliNM522, transformed with an expression library that was constructed with genomic DNA from a clarithromycin-resistant strain of H. pylori, revealed six clones that conferred clarithromycin resistance consistently after retransformation. Southern hybridization and DNA sequencing revealed that four of the six clones contained the same locus. Comparison of DNA and amino acid sequences showed that the 1.3-kb DNA fragment had significant homology to the 3-oxoadipate CoA-transferase subunit A (yxjD) and subunit B (yxjE) of Bacillus subtilis. However, the clarithromycin inactivation assay and knockout mutation analysis showed that the gene increased clarithromycin resistance in E. coli, but not in H. pylori. In contrast, sequencing of the 23S rRNA gene in six clarithromycin-resistant H. pylori clinical isolates revealed an A to G transitional mutation at position 2515 of the 23S rRNA gene in all isolates. Natural transformation with the 23S rRNA gene from resistant strains conferred clarithromycin resistance in clarithromycin-sensitive strains. We conclude that the 23S rRNA mutation is sufficient to confer clarithromycin resistance and that it is the major mechanism of clarithromycin resistance in H. pylori.

Glans sculpting in phalloplasty--experiences in female-to-male transsexuals

An aesthetically appealing neophallus with an urethral meatus at its tip is one of the goals of phalloplasty in female-to-male transsexuals. From July 1993 to December 1996, 20 cases of female-to-male transsexuals who had received sculpting of glans in four different ways were enrolled. Their photographs were collected and were scored by independent surgical and non-surgical assessors. The Norfolk procedure creates a more normal neoglans assessed by patients themselves and by the assessors. Split-thickness skin graft (SSG) produces a more normal-looking coronal sulcus than full-thickness skin graft (FTSG) in the Norfolk procedure.

An immunohistochemical study of E-cadherin expression with correlations to clinicopathological features in gastric cancer

BACKGROUND/AIMS

Reduced expression of E-cadherin leading to loss of cellular adhesion is crucial for cancer invasion and metastasis. The aim of this study is to investigate the role of E-cadherin in gastric tumorigenesis.

METHODOLOGY

Immunohistochemical expression of E-cadherin was analyzed and correlated with clinicopathological characteristics of 122 patients with gastric cancer.

RESULTS

Reduced E-cadherin expression was noted in 71 tumors (58.2%), while all normal epithelium showed a normal expression. Correlation of E-cadherin status to histological subtypes and growth patterns revealed a significantly higher frequency of reduced expression in diffuse type (46/60, 76.7%), advanced tumors (48/68, 70.6%) and stage III/IV (39/53, 73.6%) than that in intestinal type (25/62, 40.3%, p<0.0001), early tumors (23/54, 42.6%, p<0.005) and stage I/II (32/69, 46.4%, p<0.005) respectively. Moreover, abnormal expression was more frequent in tumors with positive lymph node metastasis (45/62, 72.6%), peritoneum seeding (10/11, 90.9%) and venous permeation (27/37, 73%) than that in tumors without lymph node metastasis (26/60, 43.3%, p<0.005), peritoneum seeding (61/111, 55.0%, p<0.05) and venous permeation (44/85, 51.8%, p<0.05). There is no statistical difference between E-cadherin expression and the status of perineural invasion or H. pylori infection. Analysis of survival for patients demonstrated that reduced E-cadherin expression was correlated with poor prognosis.

CONCLUSIONS

These data indicate that impaired expression of E-cadherin is an important characteristic of gastric cancer and contributes to histogenesis, tumor growth, metastasis and poor survival.

Gastric cancer risk in relation to Helicobacter pylori infection and subtypes of intestinal metaplasia

Helicobacter pylori (H. pylori) infection and intestinal metaplasia (IM) are each associated with an increased risk of gastric cancer (GC). To explore further the influences of H. pylori and IM on GC, H. pylori and subtypes of IM were evaluated in 135 sex and age-matched case and control pairs. Odds ratios (ORs) with 95% confidence intervals of developing GC were calculated for each risk factor using multiple logistic regression analysis. ORs for H. pylori infection and IM were 2.43 (1.29-4.65) and 4.59 (2.58-8.16), respectively, and those for different IM subtypes gave values of 0.82 (0.28-2.36) for type I, 2.03 (0.95-4.34) for type II and 39.75 (14.34-110.2) for type III. Stratification analysis by histological subtype and stage of GC showed a particularly high OR for IM in intestinal type (12.8, 4.73-34.83) and early GC (6.40, 2.25-18.18). Our data indicate that both H. pylori and IM are related to GC risk. Type III IM is a more specific marker of premalignancy, with relevance, in particular, to the early and intestinal type of GC.

Pharmacological properties of ACh receptors on the heart of the marine bivalve Meretrix lusoria

The cholinergic receptors on the heart of the marine bivalve Meretrix lusoria were used as a model to investigate their pharmacological properties in bivalves. By recording method, we measured the contractile force (CF) and the heart rate (HR) of the heart to examine the characteristics of cholinergic receptors of a marine bivalve. The known ACh receptor agonists or antagonists in vertebrate nervous system were then introduced into the heart by perfusion, to monitor their effects upon heart activities. Of the six tested agonists, two mAChR agonists (OXA-22, bethanechol) and two nAChR agonists (methylcarbachol, nicotine) mimicked the response induced by ACh. Among the seven tested antagonists, three mAChR antagonists (trihexyphenidy1, atropine and scopolamine) and three nAChR antagonists (TEA, curare and hexamethonium bromide) showed the antagonistic effects on the inhibition induced by ACh. However, there was one mAChR agonist, metoclopramide, that behaved like an ACh antagonist. Both APE (mAChR agonist) and PTMA (nAChR antagonist) showed no significant effects. This differences suggest that the pharmacological characteristics of ACh receptors on the heart of bivalve are different from those in vertebrates. It may be a novel type of ACh receptors.

Relatively low expression of multidrug resistance-1 (MDR-1) and its possible clinical implication in gastric cancers

The mechanism of drug resistance of gastric cancer cells has rarely been investigated. We specifically examine the magnitude and the biologic significance of multidrug resistance-1 (MDR-1) expression in human gastric cancer. All patients had previously been treated in prospective clinical trials for advanced gastric cancer in our institution. Patients with adequate prechemotherapy gastric cancer tissues for immunohistochemical studies by a C219 monoclonal antibody were selected for the determination of the expression rate of MDR-1. The results were designated as negative or positive by the independent interpretation of two pathologists. A subgroup of patients who had been treated with doxorubicin- or etoposide-containing regimens were selected for further correlation with drug sensitivity. Between 1990 and 1996, a total of 60 patients, 38 men and 22 women with a median age of 55 years, were studied. Eight (13.3%; 95% confidence interval, 6%-25%) of them had MDR-1 expression. None of the pertinent clinicopathologic features, including the histopathologic types of the tumors and the extent of the diseases, correlated with the expression of MDR-1. Among the 30 patients who had received doxorubicin- or etoposide-containing combination chemotherapy, 3 (10%; 95% confidence interval, 3%-27%) were designated positive for MDR-1 expression. None of the 3 patients responded to chemotherapy, whereas 19 (70.4%) of the 27 patients who had not expressed MDR-1 did respond (p=0.041 by Fisher's exact test). We conclude that the expression of MDR-1 in gastric cancer is relatively low. Its expression, however, is clinically relevant and is useful in predicting the chemoresistance of patients with gastric cancer receiving doxorubicin- or etoposide-containing combination chemotherapy.

High expression of thymidylate synthase is associated with the drug resistance of gastric carcinoma to high dose 5-fluorouracil-based systemic chemotherapy

BACKGROUND

In the past 4 years, the weekly 24-hour infusion of high dose 5-fluorouracil (5-FU) and leucovorin in the treatment of patients with advanced gastric carcinoma has been prospectively studied at the authors' institution. This has enabled them to explore the possibility that the level of expression of thymidylate synthase (TS), the target enzyme of 5-FU, is related to the drug sensitivity of gastric carcinoma to 5-FU-based chemotherapy.

METHODS

To be eligible for this study, patients were required to have received high dose 5-FU and leucovorin chemotherapy (weekly 24-hour infusions of 5-FU, 2,600 mg/m2, and leucovorin, 300 mg/m2) and to have had adequate prechemotherapy gastric carcinoma tissues for immunohistochemical study. TS106 monoclonal antibody was used to detect the expression of TS. A visual scoring system, which ranged from 0 to 3+, was adopted by 2 independent pathologists to semiquantitate the intensity of TS expression.

RESULTS

Between 1993 and 1996, a total of 30 patients, 18 men and 12 women, with a median age of 61.5 years, were enrolled. Of these patients, 16 (53.3%) and 14 (46.7%) had high and low expression of TS, respectively. Two of the 16 patients (12.5%) with high expression of TS and 13 of the 14 patients (92.9%) with low expression of TS responded to chemotherapy (P < 0.001, chi-square test). The median overall survival was 10 months for patients with low TS expression and 4 months for patients with high TS expression (P < 0.01, log rank test).

CONCLUSIONS

The data from this study suggest that the expression of TS, as determined by immunohistochemistry, is a relatively reliable indicator of whether 5-FU should be used in the treatment of patients with gastric carcinoma.

High expression of thymidylate synthase is associated with the drug resistance of gastric carcinoma to high dose 5-fluorouracil-based systemic chemotherapy

BACKGROUND

In the past 4 years, the weekly 24-hour infusion of high dose 5-fluorouracil (5-FU) and leucovorin in the treatment of patients with advanced gastric carcinoma has been prospectively studied at the authors' institution. This has enabled them to explore the possibility that the level of expression of thymidylate synthase (TS), the target enzyme of 5-FU, is related to the drug sensitivity of gastric carcinoma to 5-FU-based chemotherapy.

METHODS

To be eligible for this study, patients were required to have received high dose 5-FU and leucovorin chemotherapy (weekly 24-hour infusions of 5-FU, 2,600 mg/m2, and leucovorin, 300 mg/m2) and to have had adequate prechemotherapy gastric carcinoma tissues for immunohistochemical study. TS106 monoclonal antibody was used to detect the expression of TS. A visual scoring system, which ranged from 0 to 3+, was adopted by 2 independent pathologists to semiquantitate the intensity of TS expression.

RESULTS

Between 1993 and 1996, a total of 30 patients, 18 men and 12 women, with a median age of 61.5 years, were enrolled. Of these patients, 16 (53.3%) and 14 (46.7%) had high and low expression of TS, respectively. Two of the 16 patients (12.5%) with high expression of TS and 13 of the 14 patients (92.9%) with low expression of TS responded to chemotherapy (P < 0.001, chi-square test). The median overall survival was 10 months for patients with low TS expression and 4 months for patients with high TS expression (P < 0.01, log rank test).

CONCLUSIONS

The data from this study suggest that the expression of TS, as determined by immunohistochemistry, is a relatively reliable indicator of whether 5-FU should be used in the treatment of patients with gastric carcinoma.

Pancreas divisum coexistent with gallbladder carcinoma--report of a Chinese patient

The coexistence of pancreas divisum and gallbladder carcinoma is uncommon and, to the best of our knowledge, has never been reported in English literatures. We have encountered a 62-year-old patient with symptom of intermittent right upper quadrant abdominal pain. Abdominal ultrasonography and computed tomography showed a gallbladder tumor. Endoscopic retrograde cholangiopancreatography revealed existence of complete pancreas divisum but no anomalous union of pancreaticobiliary duct. He underwent cholecystectomy and histologic analysis revealed tubulovillous adenoma with focal malignant change in the gallbladder.

ATP-Dependent human erythrocyte glutathione-conjugate transporter. II. Functional reconstitution of transport activity

Purified dinitrophenyl S-glutathione (DNP-SG) ATPase was reconstituted into artificial liposomes prepared from soybean asolectin. Electron micrography confirmed the formation of unilamellar vesicles with an average radius of 0.25 micron. Intravesicular volume estimated by incorporation of radiolabled inulin into the vesicles was found to be 19.7 +/- 1.3 microL/mL reconstitution solution. Accumulation of the glutathione-conjugate of CDNB, DNP-SG, and of doxorubicin (DOX) in the proteoliposomes was increased in the presence of ATP as compared to equimolar ADP or adenosine 5'-[beta,gamma-methylene]triphosphate tetralithium. ATP-dependent transmembrane movement of DOX and DNP-SG into DNP-SG ATPase-reconstituted vesicles was saturable with respect to time, sensitive to the osmolarity of the assay medium, and temperature dependent. The energy of activation was found to be 12 and 15 kcal/mol for DNP-SG and DOX, respectively. Optimal temperature for transport was 37 degrees C. Saturable transport was demonstrated for DNP-SG (Vmax of 433 +/- 20 nmol/min/mg of protein, KmATP = 2.4 +/- 0. 3 mM and KmDNP-SG = 36 +/- 5 microM) as well as DOX (Vmax = 194 +/- 19 nmol/min/mg of protein, KmATP = 2.5 +/- 0.6 mM and KmDOX = 2.4 +/- 0.7 microM). The kinetic data for both DNP-SG and DOX transport were consistent with a random bi-bi sequential reaction mechanism. DOX was found to be a competitive inhibitor of DNP-SG transport with Kis of 1.2 +/- 0.2 microM and DNP-SG was found to be a competitive inhibitor of DOX transport with Kis of 13.3 +/- 2.6 microM.

Radiographic and computed tomographic findings of gastric mucosa-associated lymphoid tissue lymphomas

The purpose of this retrospective study was to evaluate the detection of gastric mucosa-associated lymphoid tissue (MALT) lymphoma lesions by upper gastrointestinal (UGI) radiography and computed tomography (CT). Fifteen patients with endoscopic biopsy-proven MALT lymphoma were included. Fourteen of these patients underwent double-contrast UGI radiography and 14 were examined with CT of the upper abdomen; 13 underwent both procedures. UGI radiography identified 88% (30/34) of lesions detected by endoscopy, including 12 of 13 enlarged rugal folds and 15 of the 17 multinodular lesions, but failed to identify two of the three ulcerative lesions. UGI radiography identified the only submucosal lesion demonstrated by endoscopy, as well as one at the gastric antrum that had been missed by endoscopy. CT demonstrated nine of 30 endoscopically proven MALT lymphoma lesions, three with focal thickening of the gastric wall and six with a lobulated inner gastric wall. CT failed to demonstrate two fundal and 19 antral or gastric body lesions. Our findings suggest that the predominant UGI features of gastric MALT lymphoma are enlarged folds and multinodular lesions. Although UGI radiography does not reveal all MALT lymphoma lesions, it may find lesions that are not detected by endoscopy. Mucosal lesions of gastric MALT lymphoma are usually not detected by CT.