			Home About us Contact

False-negative Case (false-negative + case)

Distribution by Scientific Domains

Medical Sciences	100%

Selected Abstracts

Accuracy of 18F-FDG-PET/CT for staging of oral squamous cell carcinoma,

HEAD & NECK: JOURNAL FOR THE SCIENCES & SPECIALTIES OF THE HEAD AND NECK, Issue 11 2008
MSci, Monica Pentenero DDS
Abstract Background. This study prospectively assessed 2-[F18]-fluoro-2-deoxy- D -glucose,positron emission tomography (18F-FDG-PET)/CT (PET/CT) in oral squamous cell carcinoma. Methods. Twenty-three patients completed preoperative TNM staging (CT, MR, whole-body fusion imaging PET/CT). In patients who underwent surgical therapy (19 of 23), TNM staging based on PET/CT scan was compared with pTNM. Results. PET/CT correctly staged 16 of 19 primary tumors (accuracy 84.2%, sensitivity 84.2%, positive predictive value 100%) and correctly ruled out bone invasion in 3 patients with false-positive results according to CT and/or MR. PET/CT incorrectly identified neck involvement in 5 of 15 patients (3 false positives, 2 false negatives) who underwent neck dissection (accuracy 66.7%, specificity 76.9%, negative predictive value 83.3%). False-negative cases showed a nodal size not exceeding 10 mm. One patient with a bronchial synchronous primary tumor was identified. Conclusion. PET/CT scan showed good accuracy in determining the extension and/or depth of invasion of the primary tumor. Nevertheless, PET/CT was not accurate to rule out nodal metastases. © 2008 Wiley Periodicals, Inc. Head Neck, 2008 [source]

Bone lesions: Role of sediment cytology

DIAGNOSTIC CYTOPATHOLOGY, Issue 6 2009
Surbhi Shah M.B.B.S.
Abstract This study was conducted to evaluate the role of sediment cytology of biopsy specimen fixatives, which is usually discarded, in early diagnosis of bone lesions. Cytological smears prepared from sediments of biopsy specimen fixatives (sediment cytology) were used to study 65 bone specimens biopsied with suspicion of malignancy. The cytological diagnosis was then compared with histological diagnosis, taking the latter as gold standard. Smears were adequately cellular and showed good preservation of cellular morphology. Some of the smears showed microfragments of tissue. Cytology labeled 29 lesions as malignant, 26 lesions as benign, 3 as inflammatory, and 7 smears as inconclusive because of low cell yield. Sediment cytology was able to correctly diagnose 58 of 65 lesions. There was no false-positive or false-negative case. The sediment cytology could be considered as an easy and effective diagnostic tool that can provide early diagnosis for the lesion of bone. Diagn. Cytopathol. 2009. © 2009 Wiley-Liss, Inc. [source]

Electronic Medical Record Review as a Surrogate to Telephone Follow-up to Establish Outcome for Diagnostic Research Studies in the Emergency Department

ACADEMIC EMERGENCY MEDICINE, Issue 11 2005
Jeffrey A. Kline MD
Abstract Background: Follow-up for diagnostic research studies might be facilitated if medical record review (MRR) could be used instead of telephone calls. Objectives: The authors hypothesized that MRR would yield similar accuracy to telephone follow-up. Methods: This was a secondary analysis of 2,178 initially disease-free patients who were followed after enrollment in a diagnostic study of either acute coronary syndrome (45 days) or pulmonary embolism (90 days) conducted in an urban teaching emergency department (ED). Disease status (positive or negative) was defined explicitly. Using structured data forms, trained researchers performed MRR using a comprehensive electronic database, and formulated an opinion about disease status. Trained researchers, blinded to the MRR, then dialed telephone numbers, asked questions from a script, and categorized disease status. The criterion standard was adjudication by consensus of two of three physicians who independently determined disease status based on explicit criteria and access to all follow-up data. Results: Adjudicators found that 13 of 2,178 patients developed disease during follow-up; all 13 true positives occurred among the 2,054 (94.3%) of patients who acknowledged intent to return to the study hospital. Telephone follow-up was successful in 81% of patients, and found all 13 true positives (sensitivity 100%) but with three additional false-positive cases. MRR disclosed 12 of 13 cases of disease (sensitivity 92%) with no false-positive cases. Further review of the one false-negative case from MRR revealed that it occurred after the prescribed time limit for follow-up. Conclusions: Under limited circumstances, accurate clinical follow-up for diagnostic studies conducted in the ED can be obtained by medical record review. [source]

Evaluation of chondromalacia of the patella with axial inversion recovery,fast spin-echo imaging

JOURNAL OF MAGNETIC RESONANCE IMAGING, Issue 3 2001
Sang Hoon Lee MD
The purpose of our study was to assess the accuracy of inversion recovery,fast spin-echo (IR-FSE) imaging for the evaluation of chondromalacia of the patella. Eighty-six patients were included, they underwent magnetic resonance (MR) examination and subsequent knee arthroscopy. Medial and lateral facets of the patella were evaluated separately. Axial images were obtained by using IR-FSE (TR/TE/TI = 3000/25/150 msec; echo train length, 8; 4-mm thickness; 12-cm field of view; 512 × 256 matrix; two, number of excitations) with a 1.5-T MR machine. MR interpretation of chondromalacia was made on the basis of the arthroscopic grading system. Of a total of 172 facets graded, arthroscopy revealed chondromalacia in 14 facets with various grades (G0, 158; G1, 1; G2, 3; G3, 6; G4, 4). Sensitivity, specificity, and accuracy in the chondromalacia grades were 57.1%, 93.0%, and 90.1%, respectively. There was one false-negative case (G4) and 11 false-positive cases (G1, eight; G2, two; G3, one). Sensitivity and specificity corrected by one grade difference were improved to 85.7% and 98.1%, respectively. When cartilage changes were grouped into early (corresponding to grade 1 and 2) and advanced (grade 3 and 4) diseases, sensitivity and specificity of the early and advanced diseases were 75% and 94% and 80% and 99%, respectively. IR-FSE imaging of the knee revealed high specificity but low sensitivity for the evaluation of chondromalacia of the patella. J. Magn. Reson. Imaging 2001;13:412,416. © 2001 Wiley-Liss, Inc. [source]

Clinical impact of false-negative sentinel node biopsy in primary breast cancer

BRITISH JOURNAL OF SURGERY (NOW INCLUDES EUROPEAN JOURNAL OF SURGERY), Issue 11 2002
M. T. Nano
Background: The aim was to assess the false-negative sentinel node biopsy rate in women with early breast cancer and its implications in patient treatment. Methods: Between January 1995 and March 2001, 328 consecutive patients with clinically lymph node-negative primary operable breast cancer underwent lymphatic mapping and sentinel node biopsy using a combination of preoperative lymphoscintigraphy and/or blue dye. All underwent immediate axillary dissection. The intraoperative success rate in sentinel node identification, false-negative rate, predictive value of negative sentinel node status and overall accuracy were assessed. The clinical features and primary tumour characteristics for each false-negative case were reviewed. Results: The sentinel node was identified in 285 (86·9 per cent) of 328 women. The false-negative rate was 7·9 per cent (eight of 101). Most members of the breast multidisciplinary team would have instituted adjuvant systemic therapy for six false-negative cases based on clinical features and primary tumour histology. In all, only two (0·7 per cent) of 285 women who had sentinel node biopsy may have had their management and survival prospects potentially jeopardized owing to a false-negative sentinel node. Conclusion: The results of this study suggest that the clinical impact of a false-negative sentinel node is low. © 2002 British Journal of Surgery Society Ltd [source]

Subgrouping and grading of soft-tissue sarcomas by fine-needle aspiration cytology: A histopathologic correlation study

DIAGNOSTIC CYTOPATHOLOGY, Issue 5 2001
Hal E. Palmer M.D.
Abstract To evaluate the accuracy and reproducibility of subgrouping and grading soft-tissue sarcomas by fine-needle aspiration biopsy (FNAB), a blind review was conducted of 84 FNAB specimens from 77 malignant and 7 benign soft-tissue lesions. Cytomorphologic subgroups included 31 spindle-cell, 24 pleomorphic, 11 myxoid, 7 epithelioid/polygonal, 3 small round cell, and 8 nondiagnostic cases. Malignancies included one lymphoma and 41 primary, 15 recurrent, and 20 metastatic soft-tissue sarcomas. Adequacy was defined as a majority of slides with at least 5 clusters of 10 unobscured cells. Five originally false-negative cases were considered nondiagnostic on review. Sarcoma was recognized in 59 of 64 adequate cases (92%) with available histology; however, the specific histopathologic subtype was identified in only 9 cases (14%). Benign myxoid and spindle-cell lesions were difficult to separate from low-grade sarcomas in 4 cases, and a B-cell lymphoma with sclerosis mimicked a low-grade myxoid sarcoma. The assigned cytologic grade accurately reflected the histologic grade in 90% of sarcomas when segregated into high and low grades. Pleomorphic, small round cell, and epithelioid/polygonal subgroups corresponded to high-grade sarcomas in all cases with only minor noncorrelations. Major grading noncorrelations occurred in 50% of myxoid and 9% of spindle-cell sarcomas. Therefore, attention should be given to specimen adequacy, and caution should be exercised when attempting to grade myxoid and spindle-cell sarcomas by FNAB. Diagn. Cytopathol. 24:307,316, 2001. © 2001 Wiley-Liss, Inc. [source]

Utility of an Initial D-dimer Assay in Screening for Traumatic or Spontaneous Intracranial Hemorrhage

ACADEMIC EMERGENCY MEDICINE, Issue 9 2001
Mark E. Hoffmann MD
Abstract Objective: To evaluate the sensitivity of a D-dimer assay as a screening tool for possible traumatic or spontaneous intracranial hemorrhage. If adequately sensitive, the D-dimer assay may potentially permit omission of a more expensive computed tomography (CT) scan of the head when such hemorrhage is clinically suspected. Methods: Prospective, consecutive, blinded study of patients (age > 16 years) requiring a CT scan of the head for suspected intracranial hemorrhage over a five-month period at a university, Level I trauma center. All study patients had a serum D-dimer assay obtained prior to their CT scans. Sensitivity and specificity, with 95% confidence intervals (95% CIs), of the enzyme-linked immunosorbent assay (ELISA) D-dimer assay for the detection of intracranial hemorrhage were calculated. Results: Of the 319 patients entered in the study, 25 (7.8%) had a CT scan positive for intracranial hemorrhage. Patients with intracranial hemorrhage were more likely to have a positive D-dimer assay (chi-square ? 13.075, p < 0.001). The D-dimer assay had 21 true-positive and four false-negative tests, resulting in a sensitivity of 84.0% (95% CI ? 63.7% to 95.5%) and a specificity of 55.8% (95% CI ? 55.5% to 55.9%). The four false-negative cases included one small intraparenchymal hemorrhage, one small subarachnoid hemorrhage, one moderate-sized intraparenchymal hemorrhage with mid-line shift, and one large subdural hematoma requiring emergent surgery. Conclusions: Due to the catastrophic nature of missing an intracranial hemorrhage in the emergency department, the D-dimer assay is not adequately sensitive or predictive to use as a screening tool to allow routine omission of head CT scanning. [source]

Head and neck cancer patients with pulmonary nodules: Value and role of CT-guided transthoracic needle aspiration biopsies

HEAD & NECK: JOURNAL FOR THE SCIENCES & SPECIALTIES OF THE HEAD AND NECK, Issue 11 2003
Benoît Mesurolle MD
Abstract Background. To evaluate transthoracic needle aspiration biopsies of pulmonary lesions in patients with squamous cell cancer of head and neck. Methods. Retrospective series of 85 patients with squamous cell cancer of head and neck cancer and pulmonary nodules who underwent CT-guided needle aspiration biopsy. Results. Diagnostic samples were obtained in 85% of patients. There were 8 benign and 77 malignant lesions. Among the 73 proved cases, 4 were false-negative cases. CT-guided biopsy had an accuracy of 81%, a sensitivity of 94%, and a negative predictive value of 60%. Accuracies were 68% for lesions of 20 mm or smaller and 89% for lesions greater than 20 mm. In a subset of 45 solitary lesions, among 30 positive biopsies, 15 were categorized as primary malignancies, 3 as metastatic, and 12 as indeterminate malignancies. Conclusions. In head and neck cancer patients, the prevalence of thoracic malignancies is high when a pulmonary lesion is detected. CT-guided biopsy of pulmonary lesion is an accurate procedure. However, a third of positive biopsies were categorized as indeterminate malignancies. © 2003 Wiley Periodicals, Inc. Head Neck 25: 000,000, 2003 [source]