Identification of Fungal Pathogens in Tissue Samples from Patients with Proven Invasive Infection by Fluorescence In Situ Hybridization

Author(s):  
Ilka McCormick Smith ◽  
Volker Rickerts
2014 ◽  
pp. 15-20
Author(s):  
Van Huy Tran ◽  
Thi Minh Thi Ha ◽  
Trung Nghia Van ◽  
Viet Nhan Nguyen ◽  
Phan Tuong Quynh Le ◽  
...  

Background: HER-2/neu is a predictive biomarker for treatment of gastric cancer using trastuzumab in combination with chemotherapy. This study aimed to evaluate the status of HER-2/neu gene amplification using fluorescence in situ hybridization (FISH) in gastric cancer. Patients and methods: thirty six gastric cancer patients were assessed HER-2/neu gene amplification by FISH using PathVysionTM HER-2 DNA Probe kit (including HER-2/neu probe and CEP-17 probe) with biopsy and surgical specimens. Results: The HER-2/neu gene amplification was observed in three cases (8.3%), the HER-2/neu gene amplification rate in Lauren’s intestinal-type and diffuse-type were 11.8% and 5.2%, respectively. Conclusion: We applied successfully FISH technique with gastric cancer tissue samples. This technique could be performed as routine test in gastric cancer in order to select patients that benefit from trastuzumab in combination with chemotherapy.


2001 ◽  
Vol 19 (2) ◽  
pp. 354-363 ◽  
Author(s):  
Annette Lebeau ◽  
Daniela Deimling ◽  
Christine Kaltz ◽  
Andrea Sendelhofert ◽  
Anette Iff ◽  
...  

PURPOSE: The objective of our study was to compare the methods used in the literature to analyze HER-2/neu status on archival breast cancer tissue. Therefore, a series of antibodies was evaluated to assess their immunohistochemical (IHC) sensitivity in correlation to gene amplification determined by fluorescence in situ hybridization (FISH). MATERIALS AND METHODS: HER-2/neu overexpression was studied on paraffin sections of 85 invasive breast cancers using a panel of five monoclonal (9G6, 3B5, CB11, TAB250, GSF-HER2) and two polyclonal antibodies (A8010, A0485) in addition to the HercepTest (DAKO, Glostrup, Denmark). HER-2/neu gene amplification was determined by FISH using a dual-color probe (PathVysion; Vysis, Stuttgart-Fasanenhof, Germany). RESULTS: HER-2/neu overexpression was demonstrated in 26% (9G6, TAB250, GSF-HER2), 27% (3B5, CB11), 33% (A8010) and 42% (A0485, HercepTest) of the tumors. FISH on paraffin sections identified gene amplification in 28% of the tumors. Strongly positive IHC results (3+) were always associated with gene amplification. Among the 16 tumors presented with weakly positive IHC results (2+) using the HercepTest, 12 (75%) lacked gene amplification. CONCLUSION: The comparison of IHC and FISH demonstrated an excellent correlation of high-level HER-2/neu overexpression (3+) with gene amplification; ie, FISH does not provide further information in these tumors. However, weakly positive IHC results (2+) obtained with the HercepTest share only a minor association with gene amplification.


1997 ◽  
Vol 20 (1) ◽  
pp. 97-106 ◽  
Author(s):  
Christine Hackel ◽  
Marileila Varella-Garcia

Interphase cytogenetics, utilizing fluorescence in situ hybridization (FISH) techniques, has been successfully applied to diffuse and solid tissue specimens. Most studies have been performed on isolated cells, such as blood or bone marrow cells; a few have been performed on cells from body fluids, such as amniotic fluid, urine, sperm, and sputum. Mechanically or chemically disaggregated cells from solid tissues have also been used as single cell suspensions for FISH. Additionally, intact organized tissue samples represented by touch preparations or thin tissue sections have been used, especially in cancer studies. Advantages and pitfalls of application of FISH methodology to each type of specimen and some significant biological findings achieved are illustrated in this overview.


2009 ◽  
Vol 27 (15_suppl) ◽  
pp. 5533-5533
Author(s):  
J. Qian ◽  
D. Weber ◽  
R. Cochran ◽  
D. Hossain ◽  
D. G. Bostwick

5533 Background: Endometrial cancer is the most common pelvic gynecological malignancy. The diagnosis of well-differentiated endometrial adenocarcinoma, atypical hyperplasia, and marked hyperplasia is often challenging. We sought to investigate the utility of chromosomal anomalies for the detection of uterine endometrial carcinoma using multitarget fluorescence in situ hybridization (FISH). Methods: Samples were collected by endometrial brush and processed by liquid-based thin-layer cytological preparation protocol. For study, we collected cytology slides from consecutive cases to include 50 benign, 50 hyperplasia without atypia, 50 atypical hyperplasia, and 50 endometrial cancers. Each was hybridized using fluorescence labeled DNA probes to chromosomes 1, 8, and 10 (UteroFISH). The FISH signals were enumerated in 100 cells per case, and the chromosomal anomalies were correlated with pathologic findings, including histologic diagnoses on endometrial tissue samples. Results: Numeric chromosomal anomalies were found in 0% (0/50) of benign, 20% (10/50) of hyperplasia, 76% of atypical hyperplasia (38/50), and 86% (43/50) of carcinoma specimens. The mean percentage of cells with chromosomal changes was 54% in cancer specimens, significantly higher than that in hyperplasia without atypia (13%, p< 0.0001) and atypical hyperplasia (34%, p< 0.0001). The most frequent chromosomal anomaly was gain of chromosome 1. FISH anomalies had an overall sensitivity of 81% and specificity of 90% for the detection of atypical hyperplasia and/or endometrial carcinoma. There was no association with grade of endometrial carcinoma. Conclusions: Multi-target UteroFISH appeared to be useful for the differential diagnosis of reactive hyperplasia, atypical hyperplasia, and endometrial adenocarcinoma, with a high level of sensitivity and specificity. Endometrial hyperplasia with FISH-detected chromosomal anomalies may require close clinical follow-up. No significant financial relationships to disclose.


2021 ◽  
Vol 8 (1) ◽  
pp. 13
Author(s):  
Débora Raysa Teixeira de Sousa ◽  
João Ricardo da Silva Neto ◽  
Roberto Moreira da Silva ◽  
Kátia Santana Cruz ◽  
Sven Poppert ◽  
...  

In resource-limited settings, where pneumocystosis in immunocompromised patients is infrequently observed, cost-efficient, reliable, and sensitive approaches for the diagnostic identification of Pneumocystis jirovecii in human tissue samples are desirable. Here, an in-house fluorescence in situ hybridization assay was comparatively evaluated against Grocott’s staining as a reference standard with 30 paraffin-embedded tissue samples as well as against in-house real-time PCR with 30 respiratory secretions from immunocompromised patients with clinical suspicion of pneumocystosis. All pneumocystosis patients included in the study suffered from HIV/AIDS. Compared with Grocott’s staining as the reference standard, sensitivity of the FISH assay was 100% (13/13), specificity was 41% (7/17), and the overall concordance was 66.7% with tissue samples. With respiratory specimens, sensitivity was 83.3% (10/12), specificity was 100% (18/18), and the overall concordance was 93.3% as compared with real-time PCR. It remained unresolved to which proportions sensitivity limitations of Grocott’s staining or autofluorescence phenomena affecting the FISH assay accounted for the recorded reduced specificity with the tissue samples. The assessment confirmed Pneumocystis FISH in lung tissue as a highly sensitive screening approach; however, dissatisfying specificity in paraffin-embedded biopsies calls for confirmatory testing with other techniques in case of positive FISH screening results. In respiratory secretions, acceptable sensitivity and excellent specificity were demonstrated for the diagnostic application of the P. jirovecii-specific FISH assay.


2007 ◽  
Vol 25 (18_suppl) ◽  
pp. 7570-7570 ◽  
Author(s):  
F. R. Hirsch ◽  
M. Varella-Garcia ◽  
P. A. Bunn ◽  
R. Dziadziuszko ◽  
Y. Xiao ◽  
...  

7570 Background: TRIBUTE was a phase III, placebo-controlled study of patients with previously untreated advanced NSCLC. Patients received erlotinib (E) (150 mg/d) or placebo, plus a course of 6 cycles of carboplatin and paclitaxel (CP), followed by maintenance E monotherapy (for those in the CP+E arm who were responding to treatment). 1,059 patients were randomized and treated (526 E; 533 placebo). There were no significant differences in OS, RR, or TTP between the two arms. In subgroup analyses of the pivotal 2nd line trial (BR21) of E in patients with relapsed NSCLC in which E significantly increased median survival (HR=0.71, p <0.0001), patients who scored positively for increased EGFR copy number by fluorescence in situ hybridization (FISH) exhibited prolonged OS (HR=0.44, p=0.008). Here we report on a similar subgroup analysis for TRIBUTE. Methods: FISH analysis was performed on all available tissue samples. FISH+ samples had a high level of polysomy (=four copies of the gene in =40% of cells), or gene amplification (presence of tight gene clusters, gene/chromosome per cell ratio =2, or =15 copies of the genes per cell in =10% of analyzed cells). Results: FISH analysis was successfully performed on 245 patients (121 E, 124 placebo). Outcome in the placebo patients from this subgroup was better than the overall population, suggesting that this subgroup may not be representative. Of the 100 patients (41%) that were FISH+, 33 had amplification and 67 had high polysomy. In FISH+ patients, OS was similar between those treated with CP+E and those treated with CP alone. However, FISH+ patients in the CP+E arm experienced a decrease in RR compared to those in the CP alone arm, and had a marginally significant longer TTP (HR=0.59, 0.35–0.99). The benefit in TTP appeared after approximately 6 months, during the maintenance portion of the trial. Conclusions: In this retrospective analysis, FISH+ did not predict survival benefit in TRIBUTE. A longer TTP, but a lower RR, was observed in the FISH+ patients. The lower RR in the CP+E arm in this group, taken together with the improved TTP during maintenance therapy, suggests that a non-concurrent combination approach (CP followed by E) warrants further investigation. No significant financial relationships to disclose.


2018 ◽  
Vol 18 (2) ◽  
pp. 132-140
Author(s):  
Magdalena Bogdanovska-Todorovska ◽  
Gordana Petrushevska ◽  
Vesna Janevska ◽  
Liljana Spasevska ◽  
Slavica Kostadinova-Kunovska

Accurate assessment of human epidermal growth factor receptor 2 (HER-2) is crucial in selecting patients for targeted therapy. Commonly used methods for HER-2 testing are immunohistochemistry (IHC) and fluorescence in situ hybridization (FISH). Here we presented the implementation, optimization and standardization of two FISH protocols using breast cancer samples and assessed the impact of pre-analytical and analytical factors on HER-2 testing. Formalin fixed paraffin embedded (FFPE) tissue samples from 70 breast cancer patients were tested for HER-2 using PathVysion™ HER-2 DNA Probe Kit and two different paraffin pretreatment kits, Vysis/Abbott Paraffin Pretreatment Reagent Kit (40 samples) and DAKO Histology FISH Accessory Kit (30 samples). The concordance between FISH and IHC results was determined. Pre-analytical and analytical factors (i.e., fixation, baking, digestion, and post-hybridization washing) affected the efficiency and quality of hybridization. The overall hybridization success in our study was 98.6% (69/70); the failure rate was 1.4%. The DAKO pretreatment kit was more time-efficient and resulted in more uniform signals that were easier to interpret, compared to the Vysis/Abbott kit. The overall concordance between IHC and FISH was 84.06%, kappa coefficient 0.5976 (p < 0.0001). The greatest discordance (82%) between IHC and FISH was observed in IHC 2+ group. A standardized FISH protocol for HER-2 assessment, with high hybridization efficiency, is necessary due to variability in tissue processing and individual tissue characteristics. Differences in the pre-analytical and analytical steps can affect the hybridization quality and efficiency. The use of DAKO pretreatment kit is time-saving and cost-effective.


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