Zoltan Szollosi

University of Debrecen, Debrecen, Hajdu-Bihar, Hungary

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Publications (19)44.76 Total impact

  • Article: Comparison of dual-color dual-hapten brightfield in situ hybridization (DDISH) and fluorescence in situ hybridization in breast cancer HER2 assessment.
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    ABSTRACT: The most optimal method for assessing HER2 status is still subject to controversy as far as the type of assay used, the optimal method to perform, and the costs of each assay are concerned. The current study was done as a validation study prior to setting up a clinical HER2 testing service using the new commercial dual-color dual-hapten brightfield in situ hybridization (DDISH), but it was felt that our experience may be of interest to other laboratories considering setting up HER2 diagnostic facilities. One hundred and five patients diagnosed with invasive breast cancer were selected. PathVysion FISH and DDISH assays were carried out. Concordance correlation coefficients showed near perfect agreement in average HER2 and centromere-specific signal counts per cell and in HER2/CEN17 ratios between the PathVysion and the DDISH assays, and also the Kappa measure showed near perfect agreement between the two assays (Kappa=0.8712, P<0.0001). Statistical analysis confirmed that the two assays are comparable in terms of detection of HER2 gene amplification and suggests its utilization in routine HER2 diagnostics.
    Pathology - Research and Practice 03/2013; 209(3):147-50. · 1.21 Impact Factor
  • Article: Impact of chromosome 17 centromere region assessment on HER2 status reported in breast cancer.
    Kristof Egervari, Csaba Kosa, Zoltan Szollosi
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    ABSTRACT: Recent studies have indicated that polysomy 17 is a rare event in breast cancer, and polysomy is usually mimicked in FISH analysis by gain or amplification of the centromere covered by the chromosome 17 centromere probe. To estimate the impact of chromosome 17 centromere assessment on routine practice, we conducted a retrospective re-classification study. Four hundred and five consecutive cases were selected. The original molecular pathology reports were available. Centromere 17 copy counts were ignored in the reassessment. Altogether, nineteen (4.69%) discrepant cases were found, from which five (1.23%) were considered originally non-amplified but had an HER2 copy number >6. Therefore, we reclassified them as HER2-amplified, while fourteen (3.46%) cases were originally considered amplified with 6 or fewer HER2 signals/cell. The discrepant cases found in our reassessment study would require further high-resolution genetic analysis to resolve the disagreement. On the other hand, our result also highlights that for the vast majority of breast cancer cases traditional FISH examination is still adequate to reach the correct diagnosis. This diagnostic gap must be filled by more sophisticated genetic examinations. Moreover, upcoming HER2 guidelines should consider the aid that high-resolution karyotyping can give to the diagnostic algorithm.
    Pathology - Research and Practice 08/2011; 207(8):468-71. · 1.21 Impact Factor
  • Article: Comparison of Pathvysion and Poseidon HER2 FISH assays in measuring HER2 amplification in breast cancer: a validation study.
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    ABSTRACT: The current study was done as a validation study prior to setting up a clinical HER2 testing service using the new commercial Poseidon HER2 fluorescence in situ hybridisation (FISH) assay. However, it was felt that the experience of the authors of this study may be of interest to other laboratories when considering setting up a HER2 diagnostic facility. 122 patients who had been diagnosed with invasive breast cancer were selected. Immunolabelling with HercepTest, PathVysion and Poseidon FISH assays were carried out using tissue microarray blocks. Concordance correlation coefficients showed near perfect agreement in average HER2 and centromere specific signal counts per cell and in the HER2/CEP17 ratios between the PathVysion and the Poseidon FISH assays. In addition, the kappa measure showed perfect agreement (kappa 0.9441, p<0.0001), and if only 2+ cases were considered there was substantial agreement (kappa 0.7671, p=0.0006), between the two assays. The sensitivity and the specificity of the Poseidon FISH kit were calculated to be 95.2% and 100%, respectively, whereas the positive predictive value (PPV) and negative predictive value (NPV) were 100% and 99%, respectively. With regard to the ability to presume HER2 polysomy, the Poseidon FISH kit had a sensitivity of 93.3% and a specificity of 99.1%, with PPV and NPV of 93.3% and 99.1%, respectively, as assessed with PathVysion classification as the reference. Statistical analysis confirmed that the two FISH assays are comparable in terms of detection of HER2 gene amplification. Proceeding from these findings, the genetic diagnoses obtained with the Poseidon kit can be considered to be as valuable as the results from the Food and Drug Administration approved PathVysion assay, and its utilisation in routine HER2 diagnostics is proposed.
    Journal of clinical pathology 12/2009; 63(4):341-6. · 2.43 Impact Factor
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    Article: FISH and immunohistochemical status of the hepatocyte growth factor receptor (c-Met) in 184 invasive breast tumors.
    Breast cancer research: BCR 05/2009; 11(2):402. · 5.24 Impact Factor
  • Article: An alternative and reliable real-time quantitative PCR method to determine HER2/neu amplification in breast cancer.
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    ABSTRACT: The overexpression of HER-2/neu is an independent prognostic factor of clinical outcome of breast cancer, therefore determination of HER-2/neu status is now an integral part of the clinicopathologic workup. The ways of measuring the copy number of the HER-2/neu gene in tumor cells comprise in situ hybridization techniques and real-time polymerase chain reaction (PCR). Quantitative real-time PCR is a relatively new technique for assessing HER-2/neu gene amplification with high sensitivity. However, the HER-2/neu Quantification Kit developed by Roche designed for a LightCycler 1.5 platform had been withdrawn from the commercial market; therefore, we were encouraged to design an alternative LightCycler-based method that offers the desired level of reliability. One hundred breast cancer cases with known HER-2/neu status have been examined with the original Roche developed HER-2/neu Quantification kit and the custom real-time PCR assay. The newly developed, custom PCR showed sensitivity of 91.43%, specificity of 90.63%, and accuracy of 90.91% taking fluorescence in situ hybridization results as the end point. We have described a novel real-time PCR technique for the relative quantification of the HER2/neu gene on a LightCycler 1.5 platform. We have determined that our method is eligible and ideal for the supplement of regular fluorescence in situ hybridization reactions, concerning its high sensitivity and reliability.
    Applied immunohistochemistry & molecular morphology: AIMM / official publication of the Society for Applied Immunohistochemistry 01/2009; 17(3):247-54. · 1.63 Impact Factor
  • Article: Analysis of EGFR gene amplification, protein over-expression and tyrosine kinase domain mutation in recurrent glioblastoma.
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    ABSTRACT: Gefitinib and erlotinib are both selective EGFR tyrosine kinase inhibitors (EGFR-TKIs) that have produced responses in a small subgroup of lung cancer patients. The strongest evidence for a role of EGFR in the biology of glioblastoma stems from clinical trials in which 15-20% of recurrent glioblastoma patients experienced significant tumour regression in response to these small-molecule EGFR kinase inhibitors. We examined the protein-kinase domain of the EGFR gene, EGFR protein expression and EGFR gene amplification in 20 cases of recurrent GBMs. EGFR protein over-expression was found in 65% of cases. EGFR protein over-expression was associated with EGFR gene amplification in 35% of cases, and with high polysomy in 15% of cases. No mutations were found in the TK domain of the EGFR gene. Our results confirm that mutations in the kinase domain are absent in recurrent GBM, and this might be a preponderant factor in the lack of major clinical responses of TKIs in GBM, recent studies have suggested that responsiveness to EGFR kinase inhibitors was strongly associated with coexpression of EGFRvIII and PTEN. Further prospective validation of EGFRvIII and PTEN as predictors of the clinical response to EGFR kinase inhibitors in recurrent GBM is strongly anticipated.
    Pathology & Oncology Research 09/2008; 15(2):225-9. · 1.37 Impact Factor
  • Article: Re: A new rabbit monoclonal antibody (4B5) for the immunohistochemical (IHC) determination of the HER2 status in breast cancer: comparison with CB11, fluorescence in situ hybridization (FISH), and interlaboratory reproducibility.
    Kristof Egervari, Zoltan Szollosi, Zoltan Nemes
    Applied immunohistochemistry & molecular morphology: AIMM / official publication of the Society for Applied Immunohistochemistry 07/2008; 16(5):510-1. · 1.63 Impact Factor
  • Article: Sarcoidosis in patients with mixed connective tissue disease: clinical, genetic, serological and histological observations.
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    ABSTRACT: The objective of this study was to investigate how the development of sarcoidosis influences the disease course of mixed connective tissue disease (MCTD). The cellular composition of MCTD-associated sarcoidosis granulomas was evaluated and also the disease-accompanying T-cell activation and alterations of the serum cytokine levels were measured before and after the therapy. The HLA-DR specific alleles were also assessed. We present two cases with MCTD coexisting sarcoidosis. Serum concentrations of Th1 and Th2 cytokines were assessed by ELISA. Peripheral blood CD3+ total T-cell numbers, CD4+ and CD8+ T-cell subset were determined by flow cytometry. Furthermore, hematoxylin-eosin staining and immunhistochemistry were performed for histological assessment. HLA-DR specific alleles were determined by using PCR-SSP. Elevated number of activated T-cells and high Th1 cytokine levels were detected, mainly IFN-gamma and TNF-alpha. Histologically, CD4+ and CD8+ T-cells were present in the sarcoidosis infiltrations. The haplotypes were to some extent dissimilar from the HLA-DR genotype from patients with MCTD, or sarcoidosis alone. Sarcoidosis enhances the activation of MCTD, based on the laboratory and clinical findings. Our results show that the inflammation is mainly in the effector phase, while granuloma formation is characteristic of the resolution phase of the disease. The assessment of the cytokine network in sarcoidosis-associated MCTD enables us to select the most effective, individualized therapy protocol for these patients.
    Rheumatology International 07/2008; 28(8):743-7. · 1.88 Impact Factor
  • Article: Immunohistochemical antibodies in breast cancer HER2 diagnostics. A comparative immunohistochemical and fluorescence in situ hybridization study.
    Kristof Egervari, Zoltan Szollosi, Zoltan Nemes
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    ABSTRACT: Overexpression and/or gene amplification of the HER2 oncogene predicts worse prognosis and altered sensitivity to chemotherapy. Trastuzumab is capable of improving prognosis of HER2-positive breast cancer, but for the success of treatment appropriate HER2 testing is essential. Our aim was to determine the value of immunohistochemical (IHC) screening prior to fluorescence in situ hybridization (FISH). We assessed five conventional IHC assays (NCL-CB11, Pathway CB11, CBE356, CBE1, HercepTest) and the novel rabbit monoclonal antibody, RM-4B5, combined with FISH on 199 invasive breast cancer cases. Taking FISH as the endpoint, we calculated sensitivity, specificity, positive and negative predictive values (PPV, NPV) and accuracy for all IHC assays with either taking both 2+/3+ cases or only 3+ cases as IHC positives. With 2+/3+ cases HercepTest showed 100% sensitivity and NPV, while the highest specificity, PPV and accuracy was associated with RM-4B5 (97.36, 80 and 95.34%, respectively). The second highest values belonged to either NCL-CB11 or Pathway CB11. When calculating only with 3+ cases, the results were reversed with increased specificity, PPV and accuracy. Our findings suggest that improving sensitivity by using two parallel IHC reactions might be beneficial; we recommend primarily HercepTest and Pathway CB11. Nevertheless, we may consider performing FISH analysis without prior IHC screening.
    Tumor Biology 02/2008; 29(1):18-27. · 1.94 Impact Factor
  • Article: Transformed dermatofibrosarcoma protuberans: real time polymerase chain reaction detection of COL1A1-PDGFB fusion transcripts in sarcomatous areas.
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    ABSTRACT: Recent cytogenetic studies have shown that reciprocal translocation t (17;22)(q22;q13) and a supernumerary ring chromosome derived from the translocation r(17;22) are highly characteristic of dermatofibrosarcoma protuberans (DFSP). The chromosomal rearrangements fuse the collagen type Ialpha1 (COL1A1) and the platelet-derived growth factor B-chain (PDGFB) genes. The COL1A1-PDGFB fusion transcript has been shown not only in conventional DFSP but also in a small series of DFSP with fibrosarcomatons areas (DFSP-FS) using reverse transcriptase-based conventional polymerase chain reaction. Nothing is known about the status of the COL1A1-PDGFB chimaeric gene in the pleomorphic areas of DFSP-PleoSarc (formerly known as DFSP-malignant fibrous sarcoma). To show the COL1A1-PDGFB fusion transcript in transformed malignant fibrous histiocytoma. A real-time polymerase chain reaction assay for the COL1A1-PDGFB fusion transcript in a series of DFSP containing sarcoma was conducted to determine whether the chimaeric gene could be identified in both components of DFSP-FS and DFSP-PleoSarc. Eight cases were analysed. In seven cases, transcriptable RNA was detected, and in these cases, translocations were found between COL1A1 and PDGFB genes involving exons 27, 32, 34, 40 and 47 of the COL1A1 gene and exon 2 of the PDGFB gene. From a diagnostic aspect, this assay can be particularly useful in confirming the diagnosis of sarcomatous DFSP. On the other hand, the COL1A1-PDGFB fusion gene was shown in three cases of DFSP containing pleomorphic sarcoma, which supports the theory of the common histogenesis.
    Journal of Clinical Pathology 03/2007; 60(2):190-4. · 2.31 Impact Factor
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    Article: Retrospective analysis of the prognostic role of tissue eosinophil and mast cells in Hodgkin's lymphoma.
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    ABSTRACT: The composition of reactive cell populations, which constitute the majority of tumor load in Hodgkin's lymphoma (HL), can influence the prognosis of the disease. Besides widely accepted and applied prognostic scores, the authors evaluate biological factors that may have a prognostic impact. Previous data indicate that the rate of eosinophils and mast cells in the reactive cell population, determined already at diagnosis, can be used for this purpose. Histological samples from 104 patients with HL with an average follow-up period of 110 (24-214) months were retrospectively analyzed. Mast cell positivity was associated with better overall survival, although this difference was only of borderline statistical significance (p=0.092). No significant difference was found in parameters like overall survival (OS, p=0.906) or event-free survival (EFS, p=0.307) of eosinophil-positive vs. -negative cases or in EFS (p=0.742) of mast cell-positive vs. -negative individuals (criterion for a positive specimen was more than 5% of appropriate cells in the reactive cell population). Looking at the effect of eosinophilia and mastocytosis together, there was no significant difference between the subgroups categorized according to the combined presence of the two cell types. It seems that tissue eosinophil and mast cell predominance have no prognostic value that could be used in clinical practice, although a tendency for correlation of mast cell positivity with overall survival could be seen. For a definitive statement, multicenter studies should be performed involving a higher number of patients suffering from HL.
    Pathology & Oncology Research 02/2007; 13(3):237-42. · 1.37 Impact Factor
  • Article: Tissue microarray technology in breast cancer HER2 diagnostics.
    Kristof Egervari, Zoltan Szollosi, Zoltan Nemes
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    ABSTRACT: Tissue microarrays (TMAs) as current medical research tools significantly lower the costs of immunohistochemical examinations (IHC) and fluorescence in situ hybridization (FISH) while enabling high levels of standardization and reliability. Taking HER2 testing of breast cancer into consideration, we assessed the routine applicability of TMAs. A hundred and seventy-four consecutive samples of invasive breast cancer cases were selected. TMAs were constructed in order to conduct double HER2 immunohistochemical analysis and FISH abreast using the conventional slide by slide method. Comparing the immunohistochemical data obtained from TMAs with the routinely processed large sections, we found a 94.5%/92.7%, 85.7%/88.9% and 91.2%/90% concordance at immunohistochemically HER2-negative, HER2 2+ and 3+ cases using the CB11/HercepTest, respectively. FISH performed on TMAs helped to determine Herceptin therapy suitability in all cases, and when discordance was found, we controlled FISH on "large sections". Being able to conduct FISH examinations at a reasonable price with or without prior immunohistochemical analysis, departments confronted with a certain frequency of breast cancer cases might extensively use the type of TMAs applied in our study. This is a relieve not only with regard to diagnostic work using microarrays, but this also allows to take new directions in research by shedding light on certain unusual cases.
    Pathology - Research and Practice 02/2007; 203(3):169-77. · 1.21 Impact Factor
  • Article: Comparison of immunohistochemical and fluorescence in situ hybridization assessment of HER-2 status in routine practice.
    American Journal of Clinical Pathology 02/2006; 125(1):155-6. · 2.60 Impact Factor
  • Article: Association between the Epstein-Barr virus and Hodgkin's lymphoma in the North-Eastern part of Hungary: effects on therapy and survival.
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    ABSTRACT: This retrospective study included 109 patients with Hodgkin's lymphoma (HL; 45 females, 64 males). In 47 of the 109 HL patients (43%), immunohistochemical analysis of their formalin-fixed, paraffin-embedded histologic samples revealed Epstein-Barr virus (EBV) by latent membrane protein (LMP) 1. The highest virus association (50%) was found with the mixed cellularity histologic subtype, especially in patients aged 11-20 and >50 years. Virus positivity in nodular sclerosis was 35% (negative cases accumulated in patients aged 15-30 years). Regarding clinical stages, histologic subtypes, general symptoms, treatments employed and response to treatment, the EBV-positive group was not significantly different from the virus-negative group. During the mean follow-up time of 83 months (9-300 months), the overall or event-free survival of EBV-negative patients was more favorable than that of EBV-positive patients, although the difference was not significant (p = 0.16 and p = 0.24, respectively). EBV infection may be involved in the pathogenesis of HL in our Hungarian study cohort, but it does not significantly affect clinical symptoms, therapeutic results or complete and event-free survival of HL patients.
    Acta Haematologica 01/2006; 116(2):101-7. · 1.35 Impact Factor
  • Article: Re: Lottner et al. simultaneous detection of HER2/neu gene amplification and protein overexpression in paraffin-embedded breast cancer. J Pathol 2005; 205: 577-584.
    The Journal of Pathology 10/2005; 207(1):119-20; author reply 121-2. · 6.32 Impact Factor
  • Article: Histiocyte-like cells expressing factor XIIIa do not belong to the neoplastic cell population in malignant fibrous histiocytoma.
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    ABSTRACT: The term malignant fibrous histiocytoma (MFH) is widely used for pleomorphic soft tissue sarcomas without a specific line of differentiation. MFH is included in the category of fibrohistiocytic soft tissue tumors. MFH has a broad range of histological appearances, and it has several subtypes. All of these subtypes are composed of spindled fibroblast-like cells, undifferentiated cells, and histiocytic or histiocyte-like cells. A large number of fibroblast-like and pleomorphic cells express factor XIIIa in MFH. The cytological pleomorphism of factor XIIIa cells suggests that these cells may belong to the neoplastic population. It is equally possible that the factor XIIIa-positive cells are only activated stromal cells. The relation of factor XIIIa-positive cells to the neoplastic cell population in MFH is addressed in the present study. A morphometric approach compares the measure of nuclear pleomorphism of the factor XIIIa-positive cells with that of the factor XIIIa-negative tumor cells in high-grade MFH. The immunohistochemical approach compares the factor XIIIa-positive and -negative cell populations with regard to mutations of p53 tumor suppressor gene in p53-positive MFH cases. We selected 58 cases of soft tissue pleomorphic or storiform-pleomorphic MFH on the basis of histopathological examinations. A combination of incident light immunofluorescence for factor XIIIa and transmitted light examination for nuclear staining was used for morphometrical analysis. We found cytoplasmic factor XIIIa positivity in at least 2% of cells in 39 cases; the number of factor XIIIa-positive cells was under 0.5% in two cases, and the number of factor-positive cells ranged between 0.5% and 2% in 13 cases. Eighteen cases were analyzed with nuclear morphometry. We found that mean nuclear area and mean nuclear Ferret diameter in factor XIIIa-positive cells differed significantly from those of the tumor cells in all cases. The mean nuclear roundness factor differed significantly only in four cases. The latter finding showed that the microscopic polymorphism of factor XIIIa cells is measurable and is not merely a suspicion. The immunohistochemical positivity for p53 positivity can be accepted as the manifestation of a missense mutation of TP53 gene and as a marker of neoplastic cells. The simultaneous immunohistochemical detection of factor XIIIa and p53 in the same section revealed that factor XIIIa-positive cells were invariably p53 negative in MFH. This finding implies that the factor XIIIa cell population is non-neoplastic and belongs to the stromal component of MFH.
    Pathology - Research and Practice 02/2005; 201(5):369-77. · 1.21 Impact Factor
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    Article: Estradiol is nephroprotective in the rat remnant kidney.
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    ABSTRACT: Female sex hormones may influence the progression of renal diseases. We therefore evaluated the effects of estradiol on the development of glomerulosclerosis in a remnant kidney model. Ovariectomized or intact female Wistar rats underwent 5/6 nephrectomy. Ovariectomized animals were treated with vehicle, 17beta-estradiol alone or in combination with progesterone, intact rats received vehicle only. Twenty-four weeks after renal ablation, histological as well as molecular analysis were performed. Vehicle-treated ovariectomized animals developed severe proteinuria and glomerulosclerosis as compared with vehicle-treated intact rats. In addition, renal mRNA levels of platelet-derived growth factor-A chain (PDGF-A) were increased. Estradiol replacement reduced proteinuria, which was paralleled by a diminished glomerular injury and reduced transforming growth factor-beta1 (TGF-beta1) and PDGF-A mRNA expression. In animals that received combined hormone treatment there were no significant differences in proteinuria, creatinine clearance, renal histopathology and growth factor mRNA levels compared with those measured in vehicle-treated ovariectomized rats. Serum cholesterol and triglyceride levels were comparable between all groups during the whole follow-up period. The data suggest that estrogens protect against the development of glomerulosclerosis in the rat remnant kidney model.
    Nephrology Dialysis Transplantation 02/2003; 18(1):54-61. · 3.40 Impact Factor
  • Article: Pseudoaneurysm and ilio-caval fistula caused by malignant fibrous histiocytoma of the aorta--CT diagnosis and angiographic confirmation.
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    ABSTRACT: We report a case of a malignant fibrous histiocytoma (MFH) of the aortic bifurcation, which manifested as a pseudoaneurysm with the formation of an ilio-caval fistula, a complication about which, to our knowledge, nothing has been published previously. Spiral CT, catheter arteriography and venography were complementary in the diagnostic procedure.
    European Radiology 03/2002; 12(2):450-3. · 3.22 Impact Factor
  • Article: [Without Title]
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    ABSTRACT: We report a case of a malignant fibrous histiocytoma (MFH) of the aortic bifurcation, which manifested as a pseudoaneurysm with the formation of an ilio-caval fistula, a complication about which, to our knowledge, nothing has been published previously. Spiral CT, catheter arteriography and venography were complementary in the diagnostic procedure.
    European Radiology 01/2002; 12(2):450-453. · 3.22 Impact Factor