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51.
Recent studies delineated two different patterns of tumor growth in colorectal carcinoma characterized as polypoid and nonpolypoid (PG-type and NPG-type, respectively). We quantified serum sialyl Lewis (Le)a (CA19–9), sialyl Lex (SLX), sialyl Tn (STN), and carcinoembryonic antigen (CEA) in 269 colorectal cancer patients to establish whether their levels correlated with any biological or clinical differences between PG-type and NPG-type cancer. Patients were divided into high and low antigen groups (higher or lower than a selected diagnostic-based cut-off value) and compared. Statistical testing was by univariate and multivariate (logistic regression) analyses. Forty-seven (17.5%) patients with PG-type and 222 (82.5%) with NPG-type cancer were studied. In contrast to NPG-type, the characteristics of the PG-type cancers included a low rate of lymph node metastasis and a high serum STN level. In contrast to a low STN level, a high STN level was independently related to the presence of distant metastasis in patients with PG-type cancer, and also to the presence of distant metastasis and large-sized tumor in patients with NPG-type cancer. These data suggest that differences in STN levels in the serum of patients with PG-type or NPG-type colorectal carcinomas may be at least partly responsible for different tumor progression behavior. Received: 17 December 1999 / Accepted: 6 March 2000  相似文献   
52.
The deletion of blood group ABH isoantigens on tumor tissues has been reported to be an adverse prognostic marker for patients with various solid tumors. In the present study, we evaluated the prognostic value of altered expression of ABH isoantigens in colorectal carcinomas. Using monoclonal antibodies, the expression of A, B, and H antigens was assessed by immunohistochemistry on paraffin-embedded carcinoma samples from 82 patients who had undergone surgery for colorectal cancer. ABH isoantigens were found to be deleted in 36 carcinomas (43.9%) and expressed in 46 (56.1%). Univariate and multivariate analysis using a logistic regression model revealed that N factor (lymph node metastasis) and blood group type were independently related to the expression of ABH isoantigens. In contrast to previous reports on other cancers, patients whose colorectal carcinomas express ABH isoantigens had a poorer prognosis than those whose carcinomas showed deletion of ABH isoantigens (P = 0.0008). The expression of ABH isoantigens was an independent prognostic variable, in addition to T (depth of tumor invasion), N, and M (distant metastasis) factors, as shown by means of Cox regression analysis. In conclusion, the expression of ABH isoantigens in carcinoma tissue is an important poor prognostic factor in patients with colorectal cancer. This variable needs to be considered in the design of future trials of therapy. Received: 20 August 1999 / Accepted: 16 December 1999  相似文献   
53.
This study was designed to provide a histopathological analysis focusing on fibrosis (staging) and necroinflammatory reaction (grading, hepatitis activity index: HAI) in noncancerous liver tissue, and mitotic index (MI) in cancerous liver tissue to predict prognosis in 81 patients with chronic hepatitis or cirrhosis who underwent hepatectomy for hepatocellular carcinoma (HCC). The incidence of grade 2/3 and higher HAI was higher in patients with viral hepatitis C. The incidence of grade 2/3 was associated with vascular invasion of HCC, postoperative liver dysfunction, and cancer recurrence. Higher MI (5) was significantly associated with vascular invasion, poor histological differentiation, and recurrence rate (P < 0.05). Multivariate analysis showed that higher grade was the factor strongly associated with cancer recurrence (odds ratio: 10.621, P = 0.006). Higher MI correlated with overall patient survival (P < 0.05) by univariate analysis. Grading and MI are the useful prognostic markers for predicting tumor recurrence and patient survival.  相似文献   
54.
INTRODUCTIONHepatocellular carcinoma (HCC) is a major cause of cancer-related deaths around the world. Nearly half of patients with HCC display metastatic disease at the time of initial diagnosis, frequently involving the liver, bone, brain, lungs, and adrenal glands, but gastrointestinal involvement is rare. Melena occurring secondary to a metastatic tumor from HCC is particularly rare. Herein, we present a case of melena secondary to metastatic HCC after chemoradiation to lung and brain metastases from HCC, diagnosed preoperatively by double-balloon enteroscopy. To the best of our knowledge, this represents the first such case to be reported.PRESENTATION OF CASE60-Year-old man had been diagnosed with hepatitis B virus-associated hepatocellular carcinoma (HCC). He was readmitted for investigation of general fatigue and iron-deficiency anemia. Esophagogastroduodenoscopy, total colonoscopy, and CT failed to identify any cause for gastrointestinal bleeding. Double-balloon enteroscopy, however, revealed small bowel metastasis from HCC preoperatively. After 5 days of conservative management, segmental small bowel resection and end-to-end anastomosis were performed. The histological appearances were considered typical for moderately differentiated HCC.DISSCUSSIONEndoscopic findings of gastrointestinal metastasis from HCC vary, such as raised and centrally ulcerated lesions, polypoid tumors, or submucosal tumors. Immunohistochemical findings are thus key to differentiating HCC from adenocarcinoma in the diagnosis of GIT metastasis. Some patients with gastrointestinal bleeding remain undiagnosed even after upper endoscopy and total colonoscopy, and most such patients will display bleeding sites in the small bowel. Video capsule endoscopy and DBE have been introduced recently for the evaluation of the small bowel. DBE, which was developed by Yamamoto et al.,5 allowed us to obtain biopsy specimens, circumventing one limitation of capsule endoscopy. In this case, DBE contributed significantly to diagnosis and treatment.CONCLUSIONDBE thus seems to represent a valuable method, particularly in the preoperative setting, due to the possibility of precisely identifying the tumor site and achieving preoperative diagnosis.  相似文献   
55.

Purpose

Arterial enhancement of intrahepatic cholangiocarcinoma (ICC) has been noted. To precisely identify the characteristics of tumor enhancement patterns, we examined the relationship between CT attenuation in the tumor and clinicopathological parameters or prognosis.

Methods

Subjects were 42 ICC patients who had undergone hepatectomy. microvessel density (MVD) determined by CD34 staining was compared with imaging. Attenuation was calculated in images from multidetector CT of tumor and non-tumorous regions. Enhancement patterns were divided into two groups: arterial enhancement with higher attenuation (>16 HU; Hyper group, n = 12); and arterial enhancement with lower attenuation (Hypo group, n = 30).

Results

Univariate analysis identified high tumor marker level, increased size, less-differentiation, incomplete resection, increased bleeding, and lower MVD as significantly associated with poor survival (p < 0.05). Increased attenuation throughout the whole ICC correlated significantly with radiological findings and MVD. Concomitant hepatitis, well-differentiation, and smaller tumor were more significantly frequent in the Hyper group than in the Hypo group (p < 0.05). Postoperative early recurrence was significantly less frequent in the Hyper group, and overall survival was significantly better in the Hyper group (p < 0.05).

Conclusions

Increased CT attenuation correlated with ICC tumor vascularity. Increased tumor enhancement in the arterial phase was associated with chronic hepatitis, lower malignancy, and better survival.  相似文献   
56.
Background: Differences in the physiological stress response to pneumoperitoneal (PP) and gasless abdominal wall-lifting (AWL) procedures used for laparoscopic cholecystectomy have not been properly evaluated. Methods: We compared leukocyte count, interleukin-6 (IL-6) levels, arterial blood gases, creatinine clearance, plasma renin activity, cardiothoracic ratio, and clinical outcome in 27 patients without systemic complications who underwent laparoscopic cholecystectomy, including 11 by AWL and 16 by PP. Results: Transient leukocytosis and high IL-6 levels were observed at POD 1 (postoperative day) in both groups, but both values returned to baseline by POD 2. IL-6 levels correlated significantly with operation time (p < 0.01). Changes in blood gases, creatinine clearance, plasma renin activity, and cardiothoracic ratio were not different for the two groups. The clinical outcome was similar for both groups. Conclusions: Our results indicate that both PP and AWL are appropriate for patients without serious complications.  相似文献   
57.
Chemoradiotherapy combined cisplatin, 5-FU and radiation was carried out in an advanced esophageal cancer with suspected tracheoesophageal fistula after insertion of an expandable metallic stent. Regression of the primary tumor was observed, and oral intake could be started. Chemoradiotherapy after insertion of the expandable metallic stent was useful in this case of advanced esophageal cancer with suspected tracheoesophageal fistula.  相似文献   
58.
A case of undifferentiated spindle-cell carcinoma of the gallbladder is described. A 72-year-old man presented with right hypochondralgia and fever. Imaging studies revealed a well-demarcated solid tumor (with a necrotic center) in the gallbladder that invaded the liver and transverse colon. On gross examination of the surgical specimen, the cut surface of the polypoid tumor showed nodular invasive growth. Microscopically, the tumor was composed of atypical spindle-shaped tumor cells that proliferated in a whirling or interlacing pattern. The tumor also showed foci with a malignant epithelial component that simulated a carcinosarcoma. Immunohistochemically, the biphasic differentiation of the tumor was highlighted by the different immunoreactivity to antibodies against cytokeratins, epithelial membrane antigen (EMA), and vimentin shown by the malignant epithelial components and the spindle-cell components. However the latter showed faint positivity for cytokeratin antibody. These results suggested that the spindle-cell carcinoma of the gallbladder originated from cholecystic mucosa and showed sarcomatous reaction or dedifferentiation, as indicated by the presence of vimentin-positive cells. The proliferation index, as detected by ki-67, in the spindle-cell component was higher than that in the epithelial component, which may account for the more aggressive biological behavior of the spindle-cell component.  相似文献   
59.

Objective

The aim of this study was to investigate the correlation between the immunohistochemical expression of proliferating cell nuclear antigen (PCNA), factor VIII, and CD34 (markers of endothelial cells), and vascular endothelial growth factor (VEGF) and the recurrence of oral squamous cell carcinoma (OSCC) and oral epithelial dysplasia (OED) subjected to photodynamic therapy (PDT).

Design

Twenty-one biopsy specimens (14 cases of OSCC and 7 cases of OED) before PDT were immunohistochemically investigated in terms of their expressions of PCNA, factor VIII, CD34 and VEGF. The percentages of the total sample area that were immunopositive for factor VIII (percentage factor VIII immunopositive area: PFIA) CD34 (PCIA) and VEGF (PVIA) were calculated using computer-assisted image analysis for quantitative assessment of endothelial cells or VEGF expression in the lesions. The PCNA labelling index (LI) was evaluated as a proliferation marker.

Results

Five cases of OSCC and one case of OED recurred 4 to 30 months after PDT. We found that the average PVIA was 14.5% in the no-recurrence group and 1.7% in the recurrence group. The difference between these values was statistically significant (P = 0.0483). On the other hand, the average PCNA LI was 30.3% in the no-recurrence group and 24.3% in the recurrence group; the average PFIA was 3.7% in the no-recurrence group and 1.6% in the recurrence group; and the average PCIA was 2.0% in the no-recurrence group and 1.4% in the recurrence group. There were no significant differences between the two groups for any of these markers (P = 0.3379, P = 0.1195, P = 0.4835, respectively).

Conclusions

These results provide clinical data indicating that VEGF expression may be a useful predictive marker for the effects of PDT in OSCC and OED.  相似文献   
60.
This report describes an extremely rare adult case of an omphalomesenteric cyst resected by laparoscopic-assisted surgery. A 29-years-old Japanese man was referred and admitted to Kyushu University Hospital because of an abdominal mass and an elevated serum CEA (carcinoembryonic antigen) level (21.3 ng/mL) in August 2001. Abdominal CT and US demonstrated a cystic mass with septum and calcification. Laparoscopy showed a large mass to be attached to his abdominal wall, measuring 110 mm x 70 mm x 50 mm and filled with mucus. The mass was resected by laparoscopic-assisted surgery. The histological findings of its wall showed fibromuscular tissue, adipose tissue, calcification, and an intestinal structure. It was finally diagnosed to be an omphalomesenteric cyst.  相似文献   
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