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991.
Interlaboratory comparison of HER-2 oncogene amplification as detected by chromogenic and fluorescence in situ hybridization. 总被引:5,自引:0,他引:5
Jorma Isola Minna Tanner Amanda Forsyth Timothy G Cooke Amanda D Watters John M S Bartlett 《Clinical cancer research》2004,10(14):4793-4798
PURPOSE: Chromogenic in situ hybridization (CISH) is a new modification of the fluorescence in situ hybridization (FISH) technique for detection of oncogene amplification in archival tumor samples. In CISH, the oncogene probe is detected using a peroxidase reaction, allowing use of transmitted light microscopy. We compared detection of HER-2/neu amplification by CISH with a Food and Drug Administration-approved two-color FISH test in an interlaboratory setting. EXPERIMENTAL DESIGN: Formalin-fixed paraffin-embedded tumor samples from 197 breast cancers were analyzed for HER-2 amplification by CISH. Two-color FISH (PathVysion) CISH of 17 centromere was done if the observer considered it necessary to ascertain amplification status in tumors with borderline HER-2 CISH copy numbers. RESULTS: Paired CISH/FISH results were available from 192 (97%) of 197 cases, no clear difference in success rates of either method was observed. Centromere 17 CISH was considered necessary in seven tumors. CISH and two-color FISH results were concordant in 180 cases (93.8%). There were 92 and 88 tumors found HER-2 amplified and nonamplified, respectively, by both methods. Eight tumors were amplified by CISH but not by FISH, and four tumors exhibited the opposite condition (kappa coefficient 0.875). In 7 of 12 cases differences between the two methods could have related to a lack of CISH chromosome 17 information. The remaining cases were explained by difficult histology (ductal carcinoma in situ, poor representativity, dense lymphocytic infiltration, or intratumoral heterogeneity). CONCLUSIONS: These results indicate that CISH could provide an accurate and practical alternative to FISH for clinical diagnosis of HER-2/neu oncogene amplification in archival formalin-fixed breast cancer samples. 相似文献
992.
993.
994.
Timothy D Jones Thomas M Ulbright John N Eble Liang Cheng 《Clinical cancer research》2004,10(24):8544-8547
PURPOSE: OCT4 (POU5F1, OCT3) immunostaining highlights pluripotent cells (embryonal carcinoma and seminoma) in primary testicular germ cell tumors, but its relative usefulness in diagnosing intratubular germ cell neoplasia, unclassified (IGCNU) is not well established. The present study aimed to establish OCT4 as a sensitive and specific maker for IGCNU, a putative precursor for adult germ cell tumors. EXPERIMENTAL DESIGN: We evaluated OCT4 immunostaining in 44 cases of IGCNU from patients who had testicular germ cell tumors. In addition, 27 of the 44 IGCNU sections were also examined with antibodies to placenta-like alkaline phosphatase, the most frequently used immunohistochemical marker for intratubular germ cell neoplasia. Sections from the testes of 10 patients who had undergone orchiectomy for hormonal treatment of prostate cancer and from autopsies of 10 patients without histories of germ cell tumors were also examined for OCT4 immunostaining. The immunoreactivity of the autopsy tissues was determined with vimentin staining, and all were reactive. RESULTS: In all 44 of the cases, antibody to OCT4 marked the nuclei of nearly all of the dysplastic cells of intratubular germ cell neoplasia but not non-neoplastic testicular cells. The staining intensity was strong in every case, and there was little or no background staining. All 20 of the control specimens (10 orchiectomy specimens from prostate cancer patients and 10 testes from autopsies) were completely negative for OCT4. The 27 cases that were stained with antiplacenta-like alkaline phosphatase antibodies showed staining of variable intensity in the areas of intratubular germ cell neoplasia, and there was a high level of background staining artifact. CONCLUSIONS: OCT4 is a sensitive and specific maker for intratubular germ cell neoplasia. 相似文献
995.
Phase II trial of gefitinib in recurrent glioblastoma. 总被引:13,自引:0,他引:13
Jeremy N Rich David A Reardon Terry Peery Jeannette M Dowell Jennifer A Quinn Kara L Penne Carol J Wikstrand Lauren B Van Duyn Janet E Dancey Roger E McLendon James C Kao Timothy T Stenzel B K Ahmed Rasheed Sandra E Tourt-Uhlig James E Herndon James J Vredenburgh John H Sampson Allan H Friedman Darell D Bigner Henry S Friedman 《Journal of clinical oncology》2004,22(1):133-142
PURPOSE: To evaluate the efficacy and tolerability of gefitinib (ZD1839, Iressa; AstraZeneca, Wilmington, DE), a novel epidermal growth factor receptor tyrosine kinase inhibitor, in patients with recurrent glioblastoma. PATIENTS AND METHODS: This was an open-label, single-center phase II trial. Fifty-seven patients with first recurrence of a glioblastoma who were previously treated with surgical resection, radiation, and usually chemotherapy underwent an open biopsy or resection at evaluation for confirmation of tumor recurrence. Each patient initially received 500 mg of gefitinib orally once daily; dose escalation to 750 mg then 1,000 mg, if a patient received enzyme-inducing antiepileptic drugs or dexamethasone, was allowed within each patient. RESULTS: Although no objective tumor responses were seen among the 53 assessable patients, only 21% of patients (11 of 53 patients) had measurable disease at treatment initiation. Seventeen percent of patients (nine of 53 patients) underwent at least six 4-week cycles, and the 6-month event-free survival (EFS) was 13% (seven of 53 patients). The median EFS time was 8.1 weeks, and the median overall survival (OS) time from treatment initiation was 39.4 weeks. Adverse events were generally mild (grade 1 or 2) and consisted mainly of skin reactions and diarrhea. Drug-related toxicities were more frequent at higher doses. Withdrawal caused by drug-related adverse events occurred in 6% of patients (three of 53 patients). Although the presence of diarrhea positively predicted favorable OS from treatment initiation, epidermal growth factor receptor expression did not correlate with either EFS or OS. CONCLUSION: Gefitinib is well tolerated and has activity in patients with recurrent glioblastoma. Further study of this agent at higher doses is warranted. 相似文献
996.
An efficient and practical system for examination of the lower extremities in newborn infants and children is presented. Measurements of hip rotation and abduction are performed in a supine position. During examination, the foot is held in passive correction or induced weight-bearing position to compare the tibia, forefoot, and hindfoot alignment. Thirty-six newborn infants were examined randomly to establish standard measurements for newborns. The only statistically significant difference between male and female infants occurred in hip abduction and internal and external rotation of the hips during extension. This method of examination of the lower extremity in newborn infants is useful for routine evaluation in all children. 相似文献
997.
Hinged external fixation of the elbow: optimal axis alignment to minimize motion resistance 总被引:4,自引:0,他引:4
OBJECTIVE: To establish an optimal single hinge axis position for application of hinged external fixation to the elbow joint. DESIGN: Cadaveric biomechanical investigation. SETTING: A customized motion transducer applied passive elbow motion to six cadaveric upper extremities. The instant rotation axis of the humero-ulnar articulation was determined from three-dimensional kinematic data acquired by an electromagnetic motion tracking system. For each specimen, an optimal fixator hinge position was calculated from these motion data. INTERVENTION: A prototype articulated external fixator was applied to the elbow, first with its hinge aligned along the computed optimal position. Then the fixator was mounted in sixteen distinct off-axis positions. MAIN OUTCOME MEASURE: Additional resistance to joint motion (in terms of energy) corresponding to deliberately introduced amounts of relative malalignment between the optimal elbow axis and the actual fixator hinge axis. RESULTS: Aligning the fixator hinge along the optimized axis position resulted in a minimal amount of energy (0.15 joules) needed to rotate the elbow through a prescribed range of motion. Malpositioning the hinge by ten millimeters caused up to ten times that amount of motion resistance. CONCLUSIONS: An optimal fixator hinge position can be determined to minimize the increase in motion resistance due to fixator application. The severely increased motion resistance associated with small amounts of malalignment between the fixator hinge and the anatomic elbow axis suggests the need for highly accurate fixator hinge application. 相似文献
998.
999.
MIC-1 serum level and genotype: associations with progress and prognosis of colorectal carcinoma. 总被引:9,自引:0,他引:9
David A Brown Robyn L Ward Philip Buckhaults Tao Liu Katharine E Romans Nicholas J Hawkins Asne R Bauskin Kenneth W Kinzler Bert Vogelstein Samuel N Breit 《Clinical cancer research》2003,9(7):2642-2650
PURPOSE: Macrophage inhibitory cytokine-1 (MIC-1) is a divergent member of the tumor growth factor beta (TGF-beta) superfamily. Several observations suggest that it plays a role in colorectal carcinoma (CRC). In particular, MIC-1 is markedly up-regulated in colorectal cancers as well as in premalignant adenomas. This study examines the relationship of serum MIC-1 levels and genotypes to clinical and pathologic features of colonic neoplasia. Experimental Design: We confirmed the presence of MIC-1 in CRC tissue and the cell line CaCo-2. The normal range for serum MIC-1 levels was defined in 260 healthy blood donors, and the differences between normal subjects and 193 patients having adenomatous polyps or CRC were then determined. In a separate cohort of 224 patients, we evaluated the relationship of MIC-1 serum level and genotype to standard tumor parameters and outcome measures. RESULTS: MIC-1 was expressed in CRC tissue and the cancer cell line CaCo-2. There was a progressive increase in serum MIC-1 levels between normal individuals [mean (M) = 495 pg/ml, SD = 210), those with adenomatous polyps (M = 681 pg/ml, SD = 410), and those with CRC (M = 783 pg/ml, SD = 491)]. Serum MIC-1 level was correlated with the extent of disease so that the levels were higher in patients with higher Tumor-Node-Metastasis stage. There were significant differences in time to relapse and overall survival between subjects with different MIC-1 levels and genotypes. CONCLUSIONS: This study identifies a strong association between MIC-1 serum levels and neoplastic progression within the large bowel. We suggest that the measurement of serum MIC-1 levels and determination of MIC-1 genotype may have clinical use in the management of patients with CRC. 相似文献
1000.
The granulin-epithelin precursor/PC-cell-derived growth factor is a growth factor for epithelial ovarian cancer. 总被引:6,自引:0,他引:6