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False Positive Cases (false + positive_case)

Distribution by Scientific Domains

Medical Sciences	83%

Selected Abstracts

An audit of the accuracy of fine needle aspiration using a liquid-based cytology system in the setting of a rapid access breast clinic

CYTOPATHOLOGY, Issue 6 2002
L. Joseph
We have assessed the effectiveness and accuracy of reporting fine needle aspirates of the breast (FNAB) using a liquid-based cytology (LBC) system (the Cytospin® method) in the pressure situation of a rapid access clinic (RAC). We have reviewed every case from the RAC from June 1997 to February 2001 inclusive. There were 1322 cases, which accounted for 26% of the total FNAB received in our department over the period. There were 323 cancers and 999 benign cases in the group. The inadequate/nondiagnostic rate (C1) was 18%. The absolute sensitivity, including C1 cases, was 73% with the complete sensitivity being 90%. The groups of ,atypical, probably benign' (C3) and ,suspicious, probably malignant' (C4) accounted for a total of 6.2%. There were 28 false negative cases and 1 false positive case (a borderline phyllodes tumour). Comparing our results with the standards recommended by the NHSBSP has shown that the diagnosis of FNAB using this LBC method is feasible, accurate and reliable even in the pressure situation of a RAC. [source]

Solid renal masses in adults: Image-guided fine-needle aspiration cytology and imaging techniques,"Two Heads Better Than One?"

DIAGNOSTIC CYTOPATHOLOGY, Issue 1 2008
José García-Solano M.D.
Abstract We have compared the diagnostic accuracy of image-guided 25G-FNA (fine-needle aspiration) and imaging modalities in a group of 31 patients with solid space-occupying renal lesions. All patients had undergone total nephrectomy and histologic sections were available for review. By FNA there were 24 malignant diagnoses, I benign diagnosis, and 6 cases with yield inadequate for diagnosis. The FNA accuracy for malignancy was 100% with no false positive cases; cancer typing by FNA matched the final histologic diagnoses in 91.6% of cases. Sensitivity, specificity, positive predictive value, and negative predictive value were 80%, 14%, 80%, and 14%, respectively. Radiologically there were 26 diagnoses of malignancy, I of benignity, and 4 indeterminate lesions (IL). Accuracy for malignancy was 100%, with one false positive case; cancer typing matched the final histologic diagnoses in 84%. Sensitivity of imaging modalities was 86%, specificity 17%, positive predictive value 83%, and negative predictive value 20%. Four IL corresponded to renal cell carcinoma in the final histologic report: two IL had a previous diagnosis of malignancy by FNA, and the yield of two was inadequate for cytologic diagnosis. Both techniques have 100% accuracy for the diagnosis of malignancy. The sensitivity, specificity, positive predictive value, and negative predictive value of imaging techniques are slightly higher than those obtained by FNA. Imaging techniques and FNA of solid renal masses complement each other in IL and in nondiagnostic FNAs. Diagn. Cytopathol. 2008;36:8,12. © 2007 Wiley-Liss, Inc. [source]

O-10 Endometrial cells in cervical smears: cytological features associated with clinically significant endometrial pathology

CYTOPATHOLOGY, Issue 2007
R. N. Tiam
Introduction:, To establish the significance of cytological features which could predict clinically significant endometrial pathology, and therefore guide reporting practice in cervical samples. Methods:, A retrospective review of SurePath liquid-based cytology (LBC) cervical samples between 2002 and 2006, obtained at screening and colposcopy. These smears contained normal endometrial cells present at inappropriate times of the menstrual cycle, endometrial cells with atypia (borderline change) and with features suspicious / diagnostic of endometrial carcinoma (glandular neoplasia). False negative and false positive cases detected on subsequent histology were also included. The control group comprised negative samples and a few abnormal smears. All smears were randomly assigned and blinded to menopausal status, age, use of oral contraceptive pill and hormone replacement therapy and presence of intrauterine device. Each smear was reviewed for 16 cytologic criteria and a cytological diagnosis was given for each. Results:, A total of 219 smears were available for review; 137 were negative, out of which 85 contained normal endometrial cells, 41 contained endometrial cells with atypia, 10 contained endometrial cells with features suggestive of adenocarcinoma and 31 contained endometrial cells with features diagnostic of adenocarcinoma. The feature most associated with benign endometrial cells is top hat with central cell condensation. In contrast, the features associated with malignant endometrial cells are smooth nuclear membrane, pale chromatin, small nucleoli and scalloped borders. Discussion:, The criteria identified in this study do not definitively define a neoplastic process, but appear to be helpful in individual cases. This study emphasises that endometrial changes should be always interpreted with the relevant clinical information, which would otherwise lead to overdiagnosis in premenopausal women. [source]

Solid renal masses in adults: Image-guided fine-needle aspiration cytology and imaging techniques,"Two Heads Better Than One?"

Improved prenatal aneuploidy screening using the novel advanced first-trimester screening algorithm: A multicenter study of 10,017 pregnancies

JOURNAL OF CLINICAL ULTRASOUND, Issue 7 2008
Peter Schmidt MD
Abstract Purpose. It has been postulated that the maternal age component should be completely excluded from first-trimester screening (FTS) for fetal aneuploidies. In this study, we tested a new algorithm known as advanced first-trimester screening (AFS), which disregards maternal age. Method. In a multicenter study, FTS findings were retrieved from 10,017 pregnancies. FTS risk assessment was performed using the Nicolaides method, and the AFS score was calculated. The results of both methods were compared. Results. Within this population, 81 fetuses had an abnormal karyotype. The sensitivity of the 2 algorithms was 86.4%. When the AFS method was used, the positive predictive value rose from 9.6% (FTS) to 12.4% (AFS). Using AFS, the test positive rate could be decreased by 161 cases (,22.2%) (p < 0.0001), due to a reduction of false positive cases. As a result, the false positive rate of AFS was 24.5% lower than that of FTS, while the same number of aneuploidies was detected. Conclusion. AFS can markedly reduce the rate of false positive test results. If these results are confirmed by larger multicenter studies, the new AFS will represent a great improvement in fetal aneuploidy screening. © 2008 Wiley Periodicals, Inc. J Clin Ultrasound, 2008 [source]

Extraction and Refinement Strategy for detection of autism in 18-month-olds: a guarantee of higher sensitivity and specificity in the process of mass screening

THE JOURNAL OF CHILD PSYCHOLOGY AND PSYCHIATRY AND ALLIED DISCIPLINES, Issue 8 2009
Hideo Honda
Background:, For early detection of autism, it is difficult to maintain an efficient level of sensitivity and specificity based on observational data from a single screening. The Extraction and Refinement (E&R) Strategy utilizes a public children's health surveillance program to produce maximum efficacy in early detection of autism. In the extraction stage, all cases at risk of childhood problems, including developmental abnormality, are identified; in the refinement stage, cases without problems are excluded, leaving only cases with conclusive diagnoses. Methods:, The city of Yokohama, Japan, conducts a routine child health surveillance program for children at 18 months in which specialized public health nurses administer YACHT-18 (Young Autism and other developmental disorders CHeckup Tool), a screening instrument to identify children at risk for developmental disorders. Children who screen positive undergo further observation, and those without disorders are subsequently excluded. To study the efficacy of early detection procedures for developmental disorders, including autism, 2,814 children born in 1988, examined at 18 months of age, and not already receiving treatment for diseases or disorders were selected. Results:, In the extraction stage, 402 (14.3%) children were identified for follow-up. In the refinement stage, 19 (.7%) of these were referred to the Yokohama Rehabilitation Center and diagnosed with developmental disorders. The extraction stage produced four false negatives, bringing total diagnoses of developmental disorders to 23 (.8%) , including 5 with autistic disorder and 9 with pervasive developmental disorder , not otherwise specified (PDDNOS). Sensitivity was 60% for autistic disorder and 82.6% for developmental disorders. Specificity for developmental disorders rose to 100% with the E&R Strategy. Picture cards used in YACHT-18 provided a finer screen that excluded some false positive cases. Conclusions:, An extraction and refinement methodology utilizing child health surveillance programs achieve high efficacy for early detection of autism. [source]