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  • SAGE Publications  (50)
  • 1
    Online Resource
    Online Resource
    Cathepsin D versus Other Prognostic Factors in Breast Cancer. Results and Controversies of a Multicenter Study on 2575 Cases
    SAGE Publications ; 1996
    In:  The International Journal of Biological Markers Vol. 11, No. 3 ( 1996-07), p. 139-147
    Details
    In: The International Journal of Biological Markers, SAGE Publications, Vol. 11, No. 3 ( 1996-07), p. 139-147
    Abstract: The aim of this study was the survey of cathepsin D determination in a large group of patients enrolled at several centers, under the coordination of the Italian Committee for Quality Control in the Oncological Laboratory. Cathepsin D was measured with the same method-ology, under control of an intra and interlaboratory quality control program, in order to verify the comparability of cathepsin D results from different institutions and to analyze the frequency of cathepsin D positive cases in subgroups of patients stratified according to other prognostic parameters. This retrospective study included 2575 patients with primary breast cancer evaluat-ed in 10 institutions. Cytosol from tumor tissue was the substrate for biochemical cathepsin D, estrogen receptor and progesterone receptor determination, with an interlaboratory quality control survey provided by the E.O.R.T.C. Receptor Group and the Italian Committee for Quality Control in the Oncological Laboratory. The results of the present study can be summarized as follows: 1) Cathepsin D is independent of menopausal status; 2) In spite of standardization of tissue handling and assay methods, different results may be obtained by different institutions. It is therefore essential that each laboratory calculates its own positive/negative cutoff values prior to any routine clinical use of the parameter. This should be a serious consideration when a multicenter study is planned.
    Type of Medium: Online Resource
    ISSN: 1724-6008 , 1724-6008
    URL: Article
    DOI: 10.1177/172460089601100301
    Language: English
    Publisher: SAGE Publications
    Publication Date: 1996
    detail.hit.zdb_id: 1475778-3
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  • 2
    Online Resource
    Online Resource
    Quality Control for Estrogen and Progesterone Receptor Assay in Human Breast Cancer: The Influence of Computation Methods on Intra and Interlaboratory Variability
    SAGE Publications ; 1985
    In:  Tumori Journal Vol. 71, No. 6 ( 1985-12), p. 597-602
    Details
    In: Tumori Journal, SAGE Publications, Vol. 71, No. 6 ( 1985-12), p. 597-602
    Abstract: The importance of evaluating receptors for estrogen and progestin in human breast cancer has been pointed out by many authors. In the absence of a reference standard, receptor assays must be controlled by intra and interlaboratory quality control programs. Much interlaboratory variability exists due to non-uniform analytical protocols, non-uniform ligands, intrinsic errors and also errors in computation methods. The goals of our Italian Qualtiy Control Program on Multicenter Trials are to standardize the anaytical procedures and computation methods. Twenty Italian laboratories participated in the Quality Control Program. Each specimen was assayed for steroid receptor content according to the standardized dextran-coated-charcoal method. Data were subjected to computerized analyses by 5 different methods of calculation (Scatchard plot, direct plot, Lineweaver-Burk method, Brunauer-Emmet-Teller analysis, single-point approach). The results were than evaluated to identify intra- and inter-assay variation coefficients and to define other statistical parameters. The authors suggest different calculation methods depending on the specific experimental and/or physiopathological conditions.
    Type of Medium: Online Resource
    ISSN: 0300-8916 , 2038-2529
    URL: Article
    DOI: 10.1177/030089168507100613
    Language: English
    Publisher: SAGE Publications
    Publication Date: 1985
    detail.hit.zdb_id: 280962-X
    detail.hit.zdb_id: 2267832-3
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  • 3
    Online Resource
    Online Resource
    Quality Assurance for Steroid Receptor Assay in Human Breast Cancer: Six Years Experience of the Italian Committee
    SAGE Publications ; 1985
    In:  Tumori Journal Vol. 71, No. 6 ( 1985-12), p. 589-595
    Details
    In: Tumori Journal, SAGE Publications, Vol. 71, No. 6 ( 1985-12), p. 589-595
    Abstract: Since 1979 the quality control design proposed by the Italian ad hoc Committee has evaluated several lyophilized preparations with scalar receptor content; this permits the identification by linear regression analysis of systematic and non systematic errors. At present 41 laboratories from most of the national regions have joined the Italian Committee. The overall results of five years application of quality assurance in Italy show that there was a different pattern of imprecision with satisfactory indexes for intralaboratory performances but major variations in interlaboratory controls. There was also a remarkable difference of variability indices between the so-called « expert » and « new » laboratories; this problem can be reduced with practical seminars for new centers. On the basis of the results and experience achieved the Committee is starting another program of quality assurance for different new methodologies to provide guidelines for international working reference standards.
    Type of Medium: Online Resource
    ISSN: 0300-8916 , 2038-2529
    URL: Article
    DOI: 10.1177/030089168507100612
    Language: English
    Publisher: SAGE Publications
    Publication Date: 1985
    detail.hit.zdb_id: 280962-X
    detail.hit.zdb_id: 2267832-3
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  • 4
    Online Resource
    Online Resource
    Evaluation of Cytokeratin 19 Serum Fragments (Cyfra 21–1) in Patients with Lung Cancer: Results of a Multicenter Trial
    SAGE Publications ; 1994
    In:  The International Journal of Biological Markers Vol. 9, No. 2 ( 1994-04), p. 89-95
    Details
    In: The International Journal of Biological Markers, SAGE Publications, Vol. 9, No. 2 ( 1994-04), p. 89-95
    Abstract: Recently, a new immunometric assay (Cyfra 21–1) was developed to measure serum concentrations of a soluble fragment of cytokeratin subunit 19. With this method, supplied by Boehringer Mannheim (EIA Test Cyfra 21–1), an Italian multicenter trial was performed in patients with lung cancer. Cyfra 21–1 serum levels were determined in 568 normal subjects (blood donors), 607 patients with non-malignant diseases (491 respiratory diseases) and 730 patients with malignancies. In the latter group 584 had lung cancer. All these 584 patients had pathologically confirmed disease; 314 were epidermoid tumors, 166 adenocarcinomas, 88 small cell cancers and 16 large cell cancers. In the 568 healthy blood donors the mean Cyfra 21–1 value was 0.91 ng/ml (SD 0.47 ng/ml; range 0.05–2.90 ng/ml). A threshold of 1.9 ng/ml was chosen as the upper limit of normality. High levels of Cyfra21–1 were observed in patients with chronic hepatitis (positivity rate: 17/51–33.3%) and with pancreatitis (positivity rate 5/16 - 31.3%). In 114 out of 491 (23.2%) patients with respiratory diseases Cyfra 21–1 showed values greater than 1.9 ng/ml. The overall sensitivity (all stages) of Cyfra 21–1 in lung cancer was 65.6% (383/584). When the histology was considered the highest positivity rates were found in patients with squamous cell tumors (226/314; 72%) followed by adenocarcinomas (105/166; 63%). In patients with SCLC the global sensitivity was 52.3% (46/88). Higher sensitivity of Cyfra 21–1 was observed from stage I to stage IV (53.9% vs 85.7%; Chisquare: p 〈 0.01). When comparing patients in whom curative resections were possible (up to stage IIIa) with patients suffering from inoperable tumors, a significant difference in Cyfra 21–1 positivies was found (59% vs 81.5%; Chi square p 〈 0.01).
    Type of Medium: Online Resource
    ISSN: 1724-6008 , 1724-6008
    URL: Article
    DOI: 10.1177/172460089400900205
    Language: English
    Publisher: SAGE Publications
    Publication Date: 1994
    detail.hit.zdb_id: 1475778-3
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  • 5
    Online Resource
    Online Resource
    Clinical Profile of a New Monoclonal Antibody-Based Immunoassay for Tissue Polypeptide Antigen
    SAGE Publications ; 1994
    In:  The International Journal of Biological Markers Vol. 9, No. 4 ( 1994-10), p. 231-238
    Details
    In: The International Journal of Biological Markers, SAGE Publications, Vol. 9, No. 4 ( 1994-10), p. 231-238
    Abstract: Our preliminary evaluation of a new monoclonal antibody-based assay for tissue polypeptide antigen (TPA) has shown it to be clinically equivalent to the polyclonal antibody-based assay for TPA. The new assay (TPA-M) employs three monoclonal antibodies to epitopes on cytokeratins 8, 18 and 19. This multicenter, multinational study included 266 patients with newly diagnosed carcinomas of the lung, breast, large bowel and urinary bladder. TPA values from the two assays were compared with three other cytokeratin markers (TPS, CYFRA 21–1 and TPA Cyk ) and with the established reference markers for these malignancies (CEA and NSE for lung, CA 15–3 for breast, CEA and CA 19–9 for colorectal tumors). Analysis of receiver operating characteristic (ROC) curves in lung, colorectal and bladder cancer showed similar sensitivities for the two assays, ranging from 50% to 80% with a specificity of 95%. In breast cancer all the markers studied showed poor sensitivity. However, TPA determination by either method could discriminate advanced stage (stages III and IV) from early stage disease (stages 0 to II). TPA showed similar discriminating ability in bladder cancer. On the basis of the results obtained in our patient series, it seems that of the cytokeratin markers studied, TPA and TPA-M are the most sensitive and offer a wide range of clinical applications.
    Type of Medium: Online Resource
    ISSN: 1724-6008 , 1724-6008
    URL: Article
    DOI: 10.1177/172460089400900405
    Language: English
    Publisher: SAGE Publications
    Publication Date: 1994
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  • 6
    Online Resource
    Online Resource
    Relationship between Cytosol Tps, Tpa and Cell Proliferation
    SAGE Publications ; 1994
    In:  The International Journal of Biological Markers Vol. 9, No. 2 ( 1994-04), p. 109-114
    Details
    In: The International Journal of Biological Markers, SAGE Publications, Vol. 9, No. 2 ( 1994-04), p. 109-114
    Abstract: The serological tumor marker tissue polypeptide antigen (TPA) and the more recently identified tissue-specific polypeptide antigen (TPS) have been reported to be indicators of the proliferation rate of the tumor. In the present investigation we compared the cytosol level of the two markers with the proliferative activity of the tumor measured using the 3 H-thymidine labelling index. The preliminary results presented here show that higher TLI is associated with lower cytosol levels of both TPA and TPS. TPA and TPS in the cytosol were significantly associated. These findings are in agreement with the previously demonstrated association between high TPA cytosol levels and better prognosis in breast cancer. Further studies are ongoing in order to: 1. confirm these findings in a larger patient series; 2. investigate any possible prognostic indication provided by TPS; 3. evaluate any possible biological meaning of the negative association between TPA/ TPS and TLI in the cytosol of breast cancer.
    Type of Medium: Online Resource
    ISSN: 1724-6008 , 1724-6008
    URL: Article
    DOI: 10.1177/172460089400900208
    Language: English
    Publisher: SAGE Publications
    Publication Date: 1994
    detail.hit.zdb_id: 1475778-3
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  • 7
    Online Resource
    Online Resource
    Interchangeability and diagnostic accuracy of two assays for total and free prostate-specific antigen: two not always related items
    SAGE Publications ; 2007
    In:  The International Journal of Biological Markers Vol. 22, No. 2 ( 2007), p. 154-158
    Details
    In: The International Journal of Biological Markers, SAGE Publications, Vol. 22, No. 2 ( 2007), p. 154-158
    Type of Medium: Online Resource
    ISSN: 0393-6155
    URL: Article
    DOI: 10.5301/JBM.2008.5070
    Language: English
    Publisher: SAGE Publications
    Publication Date: 2007
    detail.hit.zdb_id: 1475778-3
    SSG: 12
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  • 8
    Online Resource
    Online Resource
    Evaluation of Critical Differences of CEA and CA15.3 Levels in Serial Samples from Patients Operated for Breast Cancer
    SAGE Publications ; 1994
    In:  The International Journal of Biological Markers Vol. 9, No. 3 ( 1994-07), p. 135-139
    Details
    In: The International Journal of Biological Markers, SAGE Publications, Vol. 9, No. 3 ( 1994-07), p. 135-139
    Abstract: In the present investigation we evaluated the variability of tumor marker levels in the follow-up of patients without evidence of disease after resection of primary breast cancer. CEA and CA15.3 were measured using commercially available methods in serial blood samples collected from 170 patients. The coefficient of variation among all samples from each patient, which accounts for the total variability (analytical variability + biological variability), was widely scattered (from 4 to 99% for CEA; from 4 to 52% for CA15.3). The critical difference was calculated using the formula designed by Eraser [CD = 2.77. (CV a 2 + CV b 2 ) 1/2 ]. It ranged from 11 to 276 for CEA and from 11 to 144 for CA15.3. From the present findings we conclude that: 1) it is possible to identify individually tailored decision criteria to evaluate tumor marker variations in the follow-up of breast cancer patients; 2) in a considerable number of cases the non-tumor-related variability is too high to allow the early identification of minor tumor marker variations that are of clinical relevance.
    Type of Medium: Online Resource
    ISSN: 1724-6008 , 1724-6008
    URL: Article
    DOI: 10.1177/172460089400900302
    Language: English
    Publisher: SAGE Publications
    Publication Date: 1994
    detail.hit.zdb_id: 1475778-3
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  • 9
    Online Resource
    Online Resource
    Interchangeability and Diagnostic Accuracy of Two Assays for Total and Free Prostate-Specific Antigen: Two not Always Related Items
    SAGE Publications ; 2007
    In:  The International Journal of Biological Markers Vol. 22, No. 2 ( 2007-04), p. 154-158
    Details
    In: The International Journal of Biological Markers, SAGE Publications, Vol. 22, No. 2 ( 2007-04), p. 154-158
    Abstract: The variation between different PSA assays seems to influence the interpretation of individual PSA values and the clinical decisions about prostate cancer. One reason for this variability could be the different reactivity of antibodies for the various molecular forms of serum PSA; as a result, samples containing the same amount of tPSA but different proportions of fPSA can produce very different values. In this study, serum samples were collected prospectively from 152 consecutive patients referred to 2 institutions (Regional Hospital, Venice, 90 subjects; San Bortolo Hospital, Vicenza, 62 subjects) for PSA elevation and/or symptoms. Serum samples were assessed according to the manufacturers’ instructions on the following 2 analyzers: the Immulite 2000 assay (Diagnostic Products Corporation, Los Angeles, USA), which measures tPSA and fPSA, and the ADVIA Centaur (Bayer Diagnostics, Tarrytown, USA), which assays tPSA and cPSA. cPSA values were transformed into fPSA by the equation fPSA=tPSA-cPSA. When taking Immulite tPSA and f/tPSA values as 100%, ADVIA Centaur values were 92.6% and 122%, respectively, which means that 20% of patients would be classified differently according to the traditional biopsy cutoff. In conclusion, there are considerable differences between the 2 methods, which could affect clinical decisions.
    Type of Medium: Online Resource
    ISSN: 1724-6008 , 1724-6008
    URL: Article
    DOI: 10.1177/172460080702200209
    Language: English
    Publisher: SAGE Publications
    Publication Date: 2007
    detail.hit.zdb_id: 1475778-3
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  • 10
    Online Resource
    Online Resource
    Quality Control for Biomarker Determination in Oncology: The Experience of the Italian Network for Quality Assessment of Tumor Biomarkers (INQAT)
    SAGE Publications ; 2002
    In:  The International Journal of Biological Markers Vol. 17, No. 3 ( 2002-07), p. 201-214
    Details
    In: The International Journal of Biological Markers, SAGE Publications, Vol. 17, No. 3 ( 2002-07), p. 201-214
    Abstract: Biomarker analysis and evaluation in oncology is the product of a number of processes (including managerial, technical and interpretation steps) which need to be monitored and controlled to prevent and correct errors and guarantee a satisfactory level of quality. Several biomarkers have recently moved to clinical validation studies and successively to clinical practice without any definition of standard procedures and/or quality control (QC) schemes necessary to guarantee the reproducibility of the laboratory information. In Italy several national scientific societies and single researchers have activated – often on a pilot level – specific external quality assessment protocols, thereby potentially jeopardizing the clinical reality even further. In view of the seriousness of the problem, in 1998 the Italian Ministry of Health sponsored a National Survey Project to coordinate and standardize the procedures and to develop QC programs for the analysis of cancer biomarkers of potential clinical relevance. Twelve QC programs focused on biomarkers and concerning morphological, immunohistochemical, biochemical, molecular, and immunoenzymatic assays were coordinated and implemented. Specifically, external QC programs for the analytical phase of immunohistochemical p53, Bcl-2, c-erb-2/neu/HER2, and microvessel density determination, of morphological evaluation of tumor differentiation grade, and of molecular p53 analysis were activated for the first time within the project. Several hundreds of Italian laboratories took part in these QC programs, the results of which are available on the web site of the Network ( www.cqlaboncologico.it ). Financial support from the Italian Government and the National Research Council (CNR) will guarantee the pursuit of activities that will be extended to new biomarkers, to preanalytical phases of the assays, and to revision of the criteria of clinical usefulness for evaluating the cost/benefit ratio.
    Type of Medium: Online Resource
    ISSN: 1724-6008 , 1724-6008
    URL: Article
    DOI: 10.1177/172460080201700310
    Language: English
    Publisher: SAGE Publications
    Publication Date: 2002
    detail.hit.zdb_id: 1475778-3
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