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71.
Background Knowledge regarding the presence and location of lymph node metastasis in gastric cancer is essential in deciding on the operative approach. Lymph node metastases have been diagnosed with imaging tests such as computed tomography (CT) and ultrasonography (US); however, the accuracy of such diagnoses, based on size and shape criteria, has not been adequate. Ferumoxtran-10 (Combidex; Advanced Magnetics) is a lymphotropic contrast agent for magnetic resonance imaging (MRI) whose efficacy for the detection of metastatic lymph nodes in various cancers has been reported by several investigators; however, its efficacy for this purpose has not been reported for gastric cancer. We investigated the efficacy of ferumoxtran-10-enhanced MRI for the diagnosis of metastases to lymph nodes in gastric cancer. Methods Seventeen consecutive patients who were diagnosed with a nonearly stage of gastric cancer were enrolled in the study. All the patients were examined by MRI (Signa Horizon 1.5 T; GE Medical; T2*-weighted images) before and 24 h after the intravenous administration of ultrasmall particles of superparamagnetic iron oxide — ferumoxtran-10 (2.6 mg Fe/kg of body weight) — and the presence or absence of metastasis was determined from the enhancement patterns. The imaging results were compared with the corresponding histopathological findings following surgery. Results Of 781 lymph nodes dissected during surgery, the imaging results of 194 nodes could be correlated with their histopathological findings. Fifty-nine lymph nodes from 11 patients had histopathological metastases. In nonaffected normal lymph nodes, we observed dark signal intensity on MRI caused by the diffuse uptake of the contrast medium by macrophages resident in the lymph nodes, which phagocytose the iron oxide particles of ferumoxtran-10. The number of phagocytic macrophages was decreased in metastatic lymph nodes, and they showed various patterns of decreased uptake of ferumoxtran-10. Three enhancement patterns were observed in lymph nodes: (A) lymph nodes with overall dark signal intensity due to the diffuse uptake of ferumoxtran-10; (B) lymph nodes with partial high signal intensity due to partial uptake; and (C) no blackening of lymph nodes due to no uptake of ferumoxtran-10. Patterns (B) and (C) were defined as metastatic. The sensitivity, specificity, positive predictive value, negative predictive value, and overall predictive accuracy of postcontrast MRI were 100% (59/59), 92.6% (125/135), 85.5% (59/69), 100% (125/125), and 94.8% (184/194), respectively. These parameters for predictive accuracy were much superior to these parameters previously evaluated by CT or US. Nodes in the retroperitoneal and paraaortic regions were more readily identified and diagnosed on the MR images than those in the perigastric region. Conclusion The present study confirmed that ferumoxtran-10-enhanced MRI is useful in the diagnosis of metastatic lymph nodes and that the use of this modality will be helpful in treatment decision-making for gastric cancer patients.  相似文献   
72.
(Received for publication on Feb. 10, 1999; accepted on Nov. 11, 1999)  相似文献   
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74.
Transformation-associated expression of Le(b) (Lewis antigen-b) or Le(Y) in human colorectal carcinomas has been well described. To examine the expression of glycosphingolipids (GSLs) bearing Lewis-phenotypes in human gynecological carcinoma-derived cells, we determined the concentrations of all GSLs. Although neither Le(b) nor Le(Y) was present in HEC-108 cells established from the poorly differentiated type of endometrial adenocarcinoma, other cell lines from moderately or well-differentiated types expressed either Le(b) or Le(Y), or both, at concentrations of 0.01 to 0.03 microg per mg of dry cells, which comprised 0.3 to 1.3% of the total GSLs. In the cervical and ovarian carcinoma-derived cell lines, Lewis phenotypes tended to be carried by nLc(4)Cer, which was accumulated in the cells without sialylation or fucosylation. These results indicated that expression of Le(b)- or Le(Y)-phenotypes was strongly dependent on the metabolic ability to supply the precursor GSLs. Both Le(b) and Le(Y) were successfully detected by monoclonal antibody MSN-1, which was a useful probe for the simultaneous detection of Le(b) and Le(Y). On application of MSN-1, either Le(b) or Le(Y) was detected in tissues from patients with well- and moderately differentiated types of endometrial adenocarcinoma at concentrations of 0.01 to 0.04 microg per mg of dry tissues, but not in the tissues of poorly differentiated type. Normal endometria at the follicular and luteal phases also contained the antigens, but the concentrations and the frequency of antigen expression were lower than those in the well- and moderately differentiated types of endometrial adenocarcinoma.  相似文献   
75.
Transformation-associated expression of Leb (Lewis antigen-b) or LeY in human colorectal carcinomas has been well described. To examine the expression of glycosphingolipids (GSLs) bearing Lewis-phenotypes in human gynecological carcinoma-derived cells, we determined the concentrations of all GSLs. Although neither Leb nor LeY was present in HEC-108 cells established from the poorly differentiated type of endometrial adenocarcinoma, other cell lines from moderately or well-differentiated types expressed either Leb or LeY, or both, at concentrations of 0.01 to 0.03 μg per mg of dry cells, which comprised 0.3 to 1.3% of the total GSLs. In the cervical and ovarian carcinoma-derived cell lines, Lewis phenotypes tended to be carried by nLc4Cer, which was accumulated in the cells without sialylation or fucosylation. These results indicated that expression of Leb- or LeY-phenotypes was strongly dependent on the metabolic ability to supply the precursor GSLs. Both Leb and LeY were successfully detected by monoclonal antibody MSN-1, which was a useful probe for the simultaneous detection of Leb and LeY. On application of MSN-1, either Leb or LeY was detected in tissues from patients with well- and moderately differentiated types of endometrial adenocarcinoma at concentrations of 0.01 to 0.04 μg per mg of dry tissues, but not in the tissues of poorly differentiated type. Normal endometria at the follicular and luteal phases also contained the antigens, but the concentrations and the frequency of antigen expression were lower than those in the well- and moderately differentiated types of endometrial adenocarcinoma.  相似文献   
76.
The anatomy of the facial nerve relative to its intratemporal and extratemporal courses varies over time with developmental changes. Otologic and parotid surgery in infants and children demands detailed knowledge of the precise anatomy of the facial nerve with respect to the tympanic ring and external auditory canal, The authors analyzed this area using our three-dimensional (3-D) computer-aided reconstruction and measurement method studying the spatial relations of the facial nerve to the tympanic ring and stylomastoid foramen. Temporal bones from five normal individuals aged 36 gestational weeks, 3 months, 8 months, 4 years, and 17 years were retrieved from the temporal bone collection stored at the Elizabeth McCullough Knowles Otopathology Laboratory in Pittsburgh. Three-dimensional reconstruction of the facial nerve comparing the developmental anatomy across the various age groups provides the surgeon with the technical information necessary to address problems in this area.  相似文献   
77.
Purpose: To investigate the effect of understanding their own disease by patients with metastatic breast cancer on their survival potential after being informed by their physician. Patientsandmethods: Two hundred and fourteen women with metastatic breast cancer who participated in a multi-institutional, randomized phase III trial (Japan Clinical Oncology Group (JCOG) Study 8808) were asked whether they understood their own disease after being given information about the clinical trial. They were classified into two groups on the basis of whether they understood or not. We estimated their survival after the time of registration and derived relative hazard ratios from Cox's proportional hazards model. Results: There were 190 patients in the better understanding group and 24 in the poor understanding group. Median survival times after registration were 28.3 and 16.1 months, respectively. The better understanding group showed a significant difference from the poor understanding group (p=0.016). In multivariate regression analysis, patients who did not understand still showed poorer survival than those who understood (hazard ratio = 2.09; 95% confidence interval (CI) 1.16–3.78; p=0.014)  相似文献   
78.
We report 7 rare cases of recurrent breast cancers who presented with central nervous system (CNS) metastases as the initial relapse site without any other organ metastases. The average age of the patients at surgery was 42.6 years old of age (median 45:range 32-60), and 6 of the 7 cases (86%) were premenopausal. The mean disease-free period was 25.7 months (median 22, range 2-60 months). The primary tumors were all invasive ductal carcinomas. The estrogen receptor and progesterone receptor status of the 3 tumors available for study were all negative. The metastatic CNS lesions included the cerebrum (4 cases), cerebellum, cervical spinal cord, and meninges. In 6 out of these 7 cases (86%), the CNS metastasis was the initial recurrent lesion. Multidisciplinary treatments including surgery, radiotherapy and systemic or intrathecal chemotherapy were given. Although the mean survival time from clinical manifestations of the metastases of the 4 deceased patients was 20 months (median 20.5; range 6-33), one patient treated with surgery and radiotherapy is been still alive18 years later. These cases were also notable for the fact that the only metastatic site was in the CNS only during the entire clinical course, except for 2 cases, one with ocular adnexa metastasis, and the other with cervical lymph node metastasis. Premenopausal patients with negative hormone receptor status are more likely to develop this type of recurrence, regardless of the histological type. It is necessary to pay attention to neurological symptoms and signs during follow-up of breast cancer patients.  相似文献   
79.
Morphometric and cell kinetic studies were performed on normal mucosa in 30 specimens of surgically resected colorectum. The average crypt length was 372 ± 57μm in the proximal colon and 506 ± 65μm in the distal colon, and the average cell numbers per crypt column in these regions were 76.4 ± 8.9 and 80.3 ± 8.8, respectively. In the proximal and distal colon, goblet cells constituted 23.3 ± 3.4% and 25.2 ± 4.0%, respectively, of the total cells in each crypt, and in both regions entero chromaffin cells constituted about 1%. The labeling indices of the proximal and distal colon were 9.4 ± 3.9% and 8.2 ± 2.2%, respectively. Combined microautoradiography and periodic acid Schiff reaction on selected cases revealed that the labeling indices of columnar cells and goblet cells were 11.0 ± 2.0% and 7.0 ± 3.2%, respectively. It was suggested that the increased number of larger goblet cells in crypts of the sigmoid colon and rectum resulted in an increase of crypt length and a decrease in the labeling index. These results provide information on the morphological and cell kinetic characteristics of normal mucosa of the colon and rectum. Acta Pathol Jpn 39: 725 730, 1989.  相似文献   
80.
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