Hand-assisted laparoscopic transhiatal esophagectomy with a systematic procedure for en bloc infracarinal lymph node dissection.

Laparoscopic transhiatal esophagectomy is a minimally invasive approach for esophageal cancer. However, a transhiatal procedure has not yet been established for en bloc mediastinal dissection. The purpose of this study was to present our novel procedure, hand-assisted laparoscopic transhiatal esophagectomy, with a systematic procedure for en bloc mediastinal dissection. The perioperative outcomes of patients who underwent this procedure were retrospectively analyzed. Transhiatal subtotal mobilization of the thoracic esophagus with en bloc lymph node dissection distally from the carina was performed according to a standardized procedure using a hand-assisted laparoscopic technique, in which the operator used a long sealing device under appropriate expansion of the operative field by hand assistance and long retractors. The thoracoscopic procedure was performed for upper mediastinal dissection following esophageal resection and retrosternal stomach roll reconstruction, and was avoided based on the nodal status and operative risk. A total of 57 patients underwent surgery between January 2012 and June 2013, and the transthoracic procedure was performed on 34 of these patients. In groups with and without the transthoracic procedure, total operation times were 370 and 216 minutes, blood losses were 238 and 139 mL, and the numbers of retrieved nodes were 39 and 24, respectively. R0 resection rates were similar between the groups. The incidence of recurrent laryngeal nerve palsy was significantly higher in the group with the transthoracic procedure, whereas no significant differences were observed in that of pneumonia between these groups. The hand-assisted laparoscopic transhiatal method, which is characterized by a systematic procedure for en bloc mediastinal dissection supported by hand and long device use, was safe and feasible for minimally invasive esophagectomy.

Comparison of changes in dental and bone radiographic densities in the presence of different soft-tissue simulators using pixel intensity and digital subtraction analyses.

OBJECTIVES: To evaluate the influence of soft-tissue simulation materials on dental and bone tissue radiographic densities using pixel intensity (PI) and digital subtraction radiography (DSR) analyses. METHODS: 15 dry human mandibles were divided into halves. Each half was radiographed using a charge-coupled device sensor without a soft-tissue simulation material (Wm) and with 5 types of materials: acrylic (Ac), wax (Wx), water (Wt), wood (Wd) and frozen bovine tissue (Bt). Three thicknesses were tested for each material: 10 mm, 15 mm and 20 mm. The material was positioned in front of the mandible and the sensor parallel to the molar region. The radiation beam was perpendicular to the sensor at 30 cm focal spot-to-object distance. The digital images of the bone and dental tissue were captured for PI analyses. The subtracted images were marked with 14 landmark magnifications, and 2 areas of analyses were defined, forming the regions of interest. Shapiro-Wilk and Kruskal-Wallis tests followed by Dunn's post-test were used (p < 0.05). RESULTS: DSR showed that both the material type and the thickness tested influenced the gain of density in bone tissue (p < 0.05). PI analyses of the bone region did not show these differences, except for the lower density observed in the image without soft-tissue simulation material. In the dental region, both DSR and PI showed that soft-tissue simulators did not influence the density in these regions. CONCLUSIONS: This study showed that the materials evaluated and their thicknesses significantly influenced the density-level gain in alveolar bone. In dental tissues, there was no density-level gain with any soft-tissue material tested.

Overexpression of RegIV in peritoneal dissemination of gastric cancer and its potential as A novel marker for the detection of peritoneal micrometastasis.

BACKGROUND: Regenerating gene type IV (RegIV) is a candidate marker for cancer and inflammatory bowel disease. In this study, its potential as a novel marker for the detection of gastric cancer peritoneal micrometastases was examined. PATIENTS AND METHODS: RegIV mRNA levels in the peritoneal washes of 95 gastric cancer patients and 22 with benign disease were quantified by real-time RT-PCR. To examine whether expression of RegIV enhance tumorigenicity or not, thirty two mice were injected intraperitoneally or subcutaneously with RegIV transfectants of TMK-1 cells, parental TMK-1 cells, or neomycin control transfectants. RESULTS: RegIV expression was markedly higher in patients with peritoneal metastases compared to those without. The level of RegIV mRNA in gastric cancer patients was related to the extent of wall penetration. A cut-off value for RegIV-positive expression was based on an analysis of negative control patients with benign disease, and gastric cancer patients above the cut-off value constituted the micrometastasis (MM+) group. Based on this criteria, 3 out of 43 T1 or T2 cases were MM+ (93% specificity). Among 15 patients with peritoneal dissemination (7 out of 15 cases were positive by cytology), 14 cases were positive for RegIV expression (93% sensitivity), while analysis of carcinoembryonic antigen (CEA) mRNA failed to detect micrometastases in 4 cases (73% sensitivity). Combined analysis of CEA and RegIV improved the accuracy of diagnosis to 100%. The prognosis of RegIV-positive cases was significantly worse than that of RegIV-negative cases. Multivariate analysis using the Cox proportional hazards model suggested that RegIV may be an independent prognostic factor. Stable expression of RegIV significantly enhanced peritoneal metastasis in an animal model of gastric cancer. CONCLUSION: These findings suggest that RegIV mRNA expression has the potential to serve as a novel marker for detecting peritoneal dissemination in gastric cancer.

Frequent silencing of RUNX3 in esophageal squamous cell carcinomas is associated with radioresistance and poor prognosis.

Radiotherapy is an effective treatment for some esophageal cancers, but the molecular mechanisms of radiosensitivity remain unknown. RUNX3, a novel tumor suppressor of gastric cancer, functions in transforming growth factor (TGF)-beta-dependent apoptosis. We obtained paired samples from 62 patients with advanced esophageal cancers diagnosed initially as T3 or T4 with image diagnosis; one sample was obtained from a biopsy before presurgical radiotherapy, and the other was resected in surgical specimens after radiotherapy. RUNX3 was repressed in 67.7% cases of the pretreatment biopsy samples and 96.7% cases of the irradiated, resected samples. The nuclear expression of RUNX3 was associated with radiosensitivity and a better prognosis than cytoplasmic or no RUNX3 expression (P<0.003); cytoplasmic RUNX3 expression was strictly associated with radioresistance. RUNX3 was downregulated and its promoter was hypermethylated in all radioresistant esophageal cancer cell lines examined. Stable transfection of esophageal cancer cells with RUNX3 slightly inhibited cell proliferation in vitro, enhanced the antiproliferative and apoptotic effects of TGF-beta and increased radiosensitivity in conjunction with Bim induction. In contrast, transfection of RUNX3-expressing cells with a RUNX3 antisense construct or a Bim-specific small interfering RNA induced radioresistance. Treatment with 5-aza-2'-deoxycytidine restored RUNX3 expression, increased radiosensitivity and induced Bim in both control and radioresistant cells. These results suggest that RUNX3 silencing promotes radioresistance in esophageal cancers. Examination of RUNX3 expression in pretreatment specimens may predict radiosensitivity, and induction of RUNX3 expression may increase tumor radiosensitivity.

In situ tissue engineering of the bile duct using polypropylene mesh-collagen tubes.

Multiple attempts have been made to replace biliary defects with a variety of materials. Recently, successful biliary reconstruction using the Gore-Tex vascular graft has been reported experimentally and clinically. We designed a new artificial bile duct consisting of collagen sponge and polypropylene mesh. We presently evaluated the feasibility of using this prosthesis as a scaffold for bile duct tissue regeneration in a canine model. Our prosthesis, a sponge made from porcine dermal collagen, is reinforced with a polypropylene mesh cylinder. We used the prosthesis to reconstruct the middle portion of the common bile duct in seven beagle dogs to evaluate its efficacy. While one dog died of biliary stricture 8 months after operation, six survived without problems to scheduled time points for tissue evaluation at 1 to 12 months. All prostheses had become completely incorporated into the host. A confluent epithelial lining was observed within 3 months. In cholangiograms the prosthesis displayed long-term patency in the six dogs and provided satisfactory bile drainage for up to 12 months. Our graft thus shows promise for repair of biliary defects and should lead to development of a new treatment for biliary reconstruction.

Comparison of simulated periodontal bone defect depth measured in digital radiographs in dedicated and non-dedicated software systems.

OBJECTIVES: To compare simulated periodontal bone defect depth measured in digital radiographs with dedicated and non-dedicated software systems and to compare the depth measurements from each program with the measurements in dry mandibles. METHODS: Forty periodontal bone defects were created at the proximal area of the first premolar in dry pig mandibles. Measurements of the defects were performed with a periodontal probe in the dry mandible. Periapical digital radiographs of the defects were recorded using the Schick sensor in a standardized exposure setting. All images were read using a Schick dedicated software system (CDR DICOM for Windows v.3.5), and three commonly available non-dedicated software systems (Vix Win 2000 v.1.2; Adobe Photoshop 7.0 and Image Tool 3.0). The defects were measured three times in each image and a consensus was reached among three examiners using the four software systems. The difference between the radiographic measurements was analysed using analysis of variance (ANOVA) and by comparing the measurements from each software system with the dry mandibles measurements using Student's t-test. RESULTS: The mean values of the bone defects measured in the radiographs were 5.07 mm, 5.06 mm, 5.01 mm and 5.11 mm for CDR Digital Image and Communication in Medicine (DICOM) for Windows, Vix Win, Adobe Photoshop, and Image Tool, respectively, and 6.67 mm for the dry mandible. The means of the measurements performed in the four software systems were not significantly different, ANOVA (P = 0.958). A significant underestimation of defect depth was obtained when we compared the mean depths from each software system with the dry mandible measurements (t-test; P approximately equal to 0.000). CONCLUSIONS: The periodontal bone defect measurements in dedicated and in three non-dedicated software systems were not significantly different, but they all underestimated the measurements when compared with the measurements obtained in the dry mandibles.

Genomic loss and epigenetic silencing of very-low-density lipoprotein receptor involved in gastric carcinogenesis.

Homozygous loss in the genomic sequence, a mechanism for inactivating tumor-suppressor genes (TSGs) in cancer, has been used as a tag for the identification of novel TSGs, and array-based comparative genomic hybridization (array-CGH) has a great potential for high-throughput identification of this change. We identified a homozygous loss of the very-low-density lipoprotein receptor (VLDLR) gene (9p24.2) from genome-wide screening for copy-number alterations in 32 gastric cancer (GC) cell lines using array-CGH. Although previous reports demonstrated mRNA or protein expression of VLDLR in various cancers including GC, the association between genomic losses or epigenetic silencing of this gene and carcinogenesis has never been reported before. Homozygous deletion of VLDLR was also seen in primary GCs, albeit infrequently, and about half of GC cell lines showed lost or reduced VLDLR expression. The VLDLR expression was restored in gene-silenced GC cells after treatment with 5-aza 2'-deoxycytidine. According to methylation analyses, hypermethylation of the VLDLR promoter region, which all of GC lines without its expression showed, occurred in some primary GCs. Restoration of VLDLR type I expression in GC cells reduced colony formation. These results suggest that not only the expression of VLDLR but also genetic or epigenetic silencing of this gene may contribute to tumor formation and be involved in gastric carcinogenesis.

Accuracy of zoomed digital image in the detection of periodontal bone defect: in vitro study.

OBJECTIVES: (1) To evaluate the intraobserver agreement related to image interpretation and (2) to compare the accuracy of 100%, 200% and 400% zoomed digital images in the detection of simulated periodontal bone defects. METHODS: Periodontal bone defects were created in 60 pig hemi-mandibles with slow-speed burs 0.5 mm, 1.0 mm, 1.5 mm, 2.0 mm and 3.0 mm in diameter. 180 standardized digital radiographs were made using Schick sensor and evaluated at 100%, 200% and 400% zooming. The intraobserver agreement was estimated by Kappa statistic (kappa). For the evaluation of diagnostic accuracy receiver operating characteristic (ROC) analysis was performed followed by chi-square test to compare the areas under ROC curves according to each level of zooming. RESULTS: For 100%, 200% and 400% zooming the intraobserver agreement was moderate (kappa=0.48, kappa=0.54 and kappa=0.43, respectively) and there were similar performances in the discrimination capacity, with ROC areas of 0.8611 (95% CI: 0.7660-0.9562), 0.8600 (95% CI: 0.7659-0.9540), and 0.8368 (95% CI: 0.7346-0.9390), respectively, with no statistical significant differences (chi2-test; P=0.8440). CONCLUSIONS: A moderate intraobserver agreement was observed in the classification of periodontal bone defects and the 100%, 200% and 400% zoomed digital images presented similar performances in the detection of periodontal bone defects.

Frequent loss of RUNX3 gene expression in remnant stomach cancer and adjacent mucosa with special reference to topography.

Our previous studies suggest that a lack of RUNX3 function is causally related to the genesis and progression of human gastric cancer. This study was conducted to determine whether alteration of RUNX3 gene expression could be detected in the normal-looking gastric remnant mucosa, and to ascertain any difference in the potential of gastric carcinogenesis between the anastomotic site and other areas in the remnant stomach after distal gastrectomy for peptic ulcer (RB group) or gastric cancer (RM group), by analysing RUNX3 expression with special reference to topography. A total of 89 patients underwent distal gastrectomy for gastric cancer from the intact stomach (GCI group) and 58 patients underwent resection of the remnant stomach for gastric cancer (RB group: 34 cases, RM group: 24 cases). We detected RUNX3 and gene promoter methylation by in situ hybridisation, quantitative reverse transcriptase-polymerase chain reaction (RT-PCR), and methylation-specific PCR. The interval between the initial surgery and surgery for remnant gastric cancer (interval time) was 10.4 years in the RM group, and 27.5 years in the RB group. Cancers in the RB group were significantly more predominant in the anastomosis area (P<0.05). Within the tumour, downregulation of RUNX3 expression ranged from 74.7 to 85.7% in the three groups. The rate of downregulation of RUNX3 of adjacent mucosa was 39.2% (11 in 28 cases) in RB and 47.6% (10 in 21 cases) in RM, which are significantly higher than that of the GCI group (19.5%, 17 in 87 cases). In noncancerous mucosa of the remnant stomach in the RB group, RUNX3 expression decreased more near the anastomosis area. In the RM group, however, there were no significant differences in RUNX3 expression by sampling location. Based on RUNX3 downregulation and clinical features, residual stomach mucosa of the RM group would have a higher potential of gastric carcinogenesis compared to the RB or GCI group. Gastric stump mucosa of the RB group has higher potential especially than other areas of residual stomach mucosa. Measurement of RUNX3 expression and detection of RUNX3 methylation in remnant gastric mucosa may estimate the forward risk of carcinogenesis in the remnant stomach.

Differential gene expression profiles of radioresistant oesophageal cancer cell lines established by continuous fractionated irradiation.

Radiation therapy is a powerful tool for the treatment of oesophageal cancer. We established radioresistant cell lines by applying fractionated irradiation in order to identify differentially expressed genes between parent and radioresistant cells. Six oesophageal cancer cell lines (TE-2, TE-5, TE-9, TE-13, KYSE170, and KYSE180) were treated with continuous 2 Gy fractionated irradiation (total dose 60 Gy). We compared expression profiles of each parent and radioresistant lines on a cDNA microarray consisting of 21168 genes. In the fractionated irradiation trial, four radioresistant sublines (TE-2R, TE-9R, TE-13R, KYSE170R) were established successfully, and we identified 19 upregulated and 28 downregulated genes common to radioresistant sublines. Upregulated genes were associated with apoptosis and inflammatory response (BIRC2 and COX-2), DNA metabolism (CD73), and cell growth (PLAU). Downregulated genes were associated with apoptosis (CASP6), cell adhesion (CDH1 and CDH3), transcription (MLL3), and cell cycle (CDK6). Some of these genes were known to be associated with radiation response, such as COX-2, but others were novel. Reverse transcription-polymerase chain reaction confirmed that genes selected by cDNA microarray were overexpressed in clinical specimens of radioresistant cases. Global gene analysis of radioresistant sublines may provide new insight into mechanisms of radioresistance and effective radiation therapy.

Overexpression of dopa decarboxylase in peritoneal dissemination of gastric cancer and its potential as a novel marker for the detection of peritoneal micrometastases with real-time RT-PCR.

We previously performed a global analysis of the gene expression of gastric cancer cell lines established from metastases to the peritoneal cavity with the cDNA microarray method, which made it possible to analyse the expression of approximately 21168 genes for the identification of novel markers for the detection of micrometastases in the peritoneal cavity. One of the upregulated genes is dopa decarboxylase (DDC), which is responsible for the synthesis of the key neurotransmitters dopamine and serotonine. We have examined its potential as a novel marker for the detection of peritoneal micrometastases of gastric cancer.DDC mRNA in the peritoneal wash from 112 gastric cancer patients was quantified for comparison of carcinoembryonic antigen (CEA) mRNA by means of real-time reverse transcriptase-polymerase chain reaction (RT-PCR) with a fluorescently labelled probe to predict peritoneal recurrence. The quantity of DDC and CEA correlated with wall penetration. Real-time RT-PCR could quantitate 10-10(6) DDC-expressing gastric cancer cells per 10(7) mesothelial cells. The cutoff value was set at the upper limit of the quantitative value for noncancer patients, and those above this cutoff value constituted the micrometastasis (MM+) group. Of 15 cases with peritoneal dissemination, 13 were MM+DDC (87% sensitivity), and one of 48 t1 cases was MM+ (98% specificity). DDC levels in peritoneal washes from patients with synchronous peritoneal metastases were more than 50 times higher than in those from patients without metastasis (P<0.01). For 15 cases of peritoneal dissemination (seven cases were cytologically positive), DDC was positive in 13 cases (87% sensitivity), but CEA failed to detect micrometastases in four cases (73% sensitivity), indicating that DDC is in some cases superior to CEA for the detection of peritoneal micrometastases of gastric cancer in terms of sensitivity as well as specificity, especially for poorly differentiated adenocarcinomas. A combination of CEA and DDC improved the accuracy of diagnosis up to 94%. These results suggest that DDC is potentially a novel marker for peritoneal dissemination of gastric cancer and that quantitative RT-PCR of DDC is reliable and efficient for the selection of patients for adjuvant intraperitoneal chemotherapy to prevent peritoneal recurrence.

A survey of radiographic prescription in dental implant assessment.

OBJECTIVES: To survey the current radiographic prescriptions in dental implant assessment amongst dentists in Brazil. METHODS: Sixty-nine dentists were interviewed during a dental implant meeting by two calibrated graduate students, using a 19-question questionnaire, considering imaging modality options both for pre-operative implant site assessment and for follow-up, particularly with respect to cost, patient radiation dose, and broad coverage of facial bones and teeth. Epi-Info 6.04 software was used to analyse the database file. RESULTS: Approximately 63.8% of the dentists prescribed only panoramic radiography for dental implant assessment and 28.9% ordered panoramic radiography plus periapical radiography and/or conventional tomography and/or computed tomography (CT). Only 7.2% of the dentists ordered conventional tomography or CT as a single examination, although 10.1% ordered it in combination with other imaging modalities. The main reasons given for prescribing panoramic radiography were broad coverage and cost (86.4%). CONCLUSIONS: This study has shown that most of the dentists in this study prescribe panoramic radiographs in dental implant assessment based on broad coverage and cost. They are not following the American Academy of Oral and Maxillofacial Radiology recommendations regarding cross-sectional imaging.

Differential gene expression profiles of gastric cancer cells established from primary tumour and malignant ascites.

Advanced gastric cancer is often accompanied by metastasis to the peritoneum, resulting in a high mortality rate. Mechanisms involved in gastric cancer metastasis have not been fully clarified because metastasis involves multiple steps and requires a combination of altered expressions of many different genes. Thus, independent analysis of any single gene would be insufficient to understand all of the aspects of gastric cancer peritoneal dissemination. In this study, we performed a global analysis of the differential gene expression of a gastric cancer cell line established from a primary main tumour (SNU-1) and of other cell lines established from the metastasis to the peritoneal cavity (SNU-5, SNU-16, SNU-620, KATO-III and GT3TKB). The application of a high-density cDNA microarray method made it possible to analyse the expression of approximately 21 168 genes. Our examinations of SNU-5, SNU-16, SNU-620, KATO-III and GT3TKB showed that 24 genes were up-regulated and 17 genes down-regulated besides expression sequence tags. The analysis revealed the following altered expression such as: (a) up-regulation of CD44 (cell adhesion), keratins 7, 8, and 14 (epitherial marker), aldehyde dehydrogenase (drug metabolism), CD9 and IP3 receptor type3 (signal transduction); (b) down-regulation of IL2 receptor gamma, IL4-Stat (immune response), p27 (cell cycle) and integrin beta4 (adhesion) in gastric cancer cells from malignant ascites. We then analysed eight gastric cancer cell lines with Northern blot and observed preferential up-regulation and down-regulation of these selected genes in cells prone to peritoneal dissemination. Reverse transcriptase-polymerase chain reaction confirmed that several genes selected by DNA microarray were also overexpressed in clinical samples of malignant ascites. It is therefore considered that these genes may be related to the peritoneal dissemination of gastric cancers. The results of this global gene expression analysis of gastric cancer cells with peritoneal dissemination, promise to provide a new insight into the study of human gastric cancer peritoneal dissemination.

Chromosomal aberrations in colorectal cancers and liver metastases analyzed by comparative genomic hybridization.

Comparative genomic hybridization (CGH) was used to screen for changes in the number of DNA sequence copies in 30 primary colorectal cancers and 16 liver metastases, to identify regions that contain genes important for the development and progression of colorectal cancer. In primary colorectal cancer, we found frequent gains at 7p21 (36.7%), 7q31-36 (30%), 8q23-24 (43.0%), 12p (30%), 14q24-32 (33.3%), 16p (40.0%), 20p (33.3%), 20q (63.3%) and 21q (36.3%), while loss was often noted at 18q12-23 (36.7%). In metastatic tumors, there were significantly more gains and losses of DNA sequences than in primary tumors, with gains at 8q23-24 (found in 62.5% of recurrences vs. 43.0% of primary tumors), 15q21-26 (37.5% vs. 20.0%), 19p (43.8% vs. 20.0%) and 20q (81.3% vs. 63.3%) and losses at 18q12-23 (50.0% vs. 36.7%). The pattern of genetic changes seen in metastatic tumors, with frequent gains at 8q23-24 and 20q and loss at 18q12-23, suggests the progression of colorectal cancer. We investigated a clinical follow-up study for all patients examined by CGH and directed our attention to the genetic changes consisting of gains at 8q and 20q. The incidence of liver metastases was higher in patients with primary colorectal cancer with these genetic changes. Gains at 8q and 20q might be useful to identify patients at high risk for developing liver metastases.

[Intraoperative coating of tumor surface using fibrin glue as a prophylaxis for cancer cell detachment].

With the aim of preventing cancer cells from becoming detached and spreading into the abdominal cavity by operative procedures during surgical resection of cancer infiltrating into gastrointestinal serosa, the exposed area of the serosa in mice was coated with fibrin glue, a biological tissue adhesive, prior to resection. We then determined whether the coating could reduce the detachment and spread of cancer cells during the surgical procedure, and thus be capable of inhibiting the occurrence of peritonitis carcinomatosa. In vitro experiments demonstrated that the fibrin glue uniformly and strongly coated the exposed area of cancer, and furthermore, that the presence of fibrin glue coating significantly reduced the number of cancer cells which became detached. As a result of using this glue, the number of deaths due to peritonitis carcinomatosa among assay mice was significantly decreased. It is therefore considered that coating the exposed area of cancer with fibrin glue inhibits cancer cells from being detached and spread during an operation, and thus can be an effective means of preventing the recurrence of peritonitis.

[Analysis of the action of dextran sulfate as a prophylaxis for peritoneal cancer metastasis, and its acting mechanism].

Although peritoneal cancer metastasis has the highest frequency of postoperative recurrence among digestive organ malignant tumors, there is no still decisive treatment. Dextran sulfate (DS) as a prophylaxis for cancer metastasis was examined with respect to its effect on cultured cells. DS was made to act on a strong adhesive neoplasm cell, and the action and acting mechanism were examined with respect to 1. readhesiveness, 2. cell cycle, and 3. gene analysis. The results suggest that: i) Once tumor cells are detached by DS, the free cells do not attach even when DS is removed, and ii) DS causes the cells to stop in the G1/G0 phase.

[Usefulness of local administration of methotrexate bound to activated carbon particles (MTX-CH)].

We developed a new dosage formulation, methotrexate bound to activated carbon particles (MTX-CH), and used it to reduce tumors via its long-acting effect at the administration sites. MTX-CH was injected locally into tumors on the back of BALB/c mice, 30 mg/mouse, as MTX and compared with mice treated with MTX aqueous solution, saline solution, activated carbon particles (CH-40) and non-treated mice. The MTX concentration at the administration sites was higher in the MTX-CH group than in the MTX aqueous solution group. A marked effect on the control of tumor growth by MTX-CH was noted after repeated administration (every 3 days, total 4 times) throughout the observation period. Although tumor size was not reduced, necrosis was microscopically observed around the site of MTX-CH administration. For the reasons mentioned above, MTX-CH is superior to MTX aqueous solution in terms of long-acting effect at the administration sites and the control of tumor growth.

Polymerase chain reaction for detection of carcinoembryonic antigen-expressing tumor cells on milky spots of the greater omentum in gastric cancer patients: a pilot study.

Our recent studies indicate that omental milky spots are frequently involved in the early stage of peritoneal cancer dissemination. We have used carcinoembryonic antigen (CEA)-specific RT-PCR for omental milky spots to predict peritoneal recurrence in gastric cancer patients. CEA mRNA was found to be positive in both 10 peritoneal washes and 16 greater omenta of 30 gastric cancer patients, including all 6 patients who showed positive results for both cytology and RT-PCR of peritoneal wash and omentum. Three of the 6 cases with positive RT-PCR in the greater omentum but not in the peritoneal wash showed recurrence of peritoneal carcinomatosa within 2 years after operation. Micrometastasis on omental milky spots was histologically confirmed in 6 of 30 gastric cancer cases. Non-specific band was detected only in the omentum of 1 case of 15 benign disease (7%), but not in peritoneal washes (0%), probably due to weak expression of CEA in mesothelial cells. Our results show that CEA-specific RT-PCR targeting micro-metastases on omental milky spots is more sensitive than targeting the peritoneal wash or conventional cytology, and suggest that this method is useful for the prediction of peritoneal recurrence in gastric cancer patients.

Relation between cyclooxygenase-2 expression and tumor invasiveness and patient survival in transitional cell carcinoma of the urinary bladder.

BACKGROUND: Expression of the inducible form of cyclooxygenase (COX)-2 is known to correlate with development of transitional cell carcinoma (TCC) of the human urinary bladder. However, the clinical significance of COX-2 expression with respect to clinicopathologic findings and patient survival is unknown. METHODS: COX-2 expression was examined immunohistochemically in tumor tissues obtained from 108 patients who underwent radical cystectomy for TCCs, without knowledge of clinicopathologic findings. Correlation between COX-2 expression and clinicopathologic findings and patient survival was determined. RESULTS: COX-2 expression was detected in 34 of 108 (31%) tumors but in none of 10 normal uroepithelial samples. Univariate logistic regression analysis showed a significant correlation between COX-2 expression and local invasion, infiltration pattern, lymphatic invasion, and venous invasion. However, multivariate logistic regression analysis revealed that only local invasion correlated significantly with COX-2 expression (P = 0.047). Cox proportional hazards regression analysis showed that both local invasion (P = 0.008) and lymph node metastasis (P = 0.001) were independent prognostic factors; however, COX-2 expression (P = 0.16) was not. CONCLUSIONS: The authors showed that COX-2 overexpression plays a role in development and invasion of TCCs, but not prognosis of patients with TCC. COX-2 inhibitors may be useful for chemoprevention of TCCs and treatment of invasive disease.

Overexpression of cyclooxygenase-2 in squamous cell carcinoma of the urinary bladder.

Epidemiological studies indicate that the development of squamous cell carcinoma of the urinary bladder is closely associated with chronic inflammation of the urinary tract, but the underlying mechanism is unknown. Cyclooxygenase (COX)-2 is involved in tumorigenesis in many tumors. The purpose of this study was to investigate the role of COX-2 in squamous cell carcinoma of the urinary bladder by immunoblot and immunohistochemical analyses. COX-2 protein was undetectable in normal bladder samples, but was expressed in 29 of 29 (100%) squamous cell carcinomas and in 8 of 8 (100%) squamous metaplasias. The expression of COX-2 showed intense, homogenous cytoplasmic immunostaining in squamous cell carcinomas. In contrast, COX-2 was heterogeneously expressed in 6 of 12 (50%) cases of transitional cell carcinoma of the bladder combined with squamous cell carcinoma, consistent with previous findings. We provide the first evidence that COX-2 is expressed in squamous cell carcinomas of the urinary bladder and in the precursor lesions, indicating its involvement in the development of this type of malignancy.