Biomedical subjects

S S Raab

Publications and source records attributed to S S Raab.

At least 55 records · Page 3Linked to original sources

PubMed1998

Interobserver variability of a Papanicolaou smear diagnosis of atypical glandular cells of undetermined significance.

The interobserver variability of a Papanicolaou smear diagnosis of atypical glandular cells of undetermined significance (AGUS) has not been measured. Four expert cytopathologists retrospectively reclassified 100 smears originally diagnosed as AGUS; on follow-up examination, 54 had a clinically significant lesion and 46 had a benign lesion. The mean sensitivity and specificity of reclassification were 86% and 21%, respectively. The kappa statistic for pairwise cytopathologist comparison varied from 0.16 to 0.27. In 45% of cases the cytopathologists all used different Bethesda System diagnoses, and in no case did all the cytopathologists use the same diagnosis. There was little agreement on which cytologic criteria were important in separating clinically significant and benign lesions. We conclude the following: interobserver agreement in reclassifying AGUS lesions is very poor; the AGUS category is poorly understood, and there is no agreement on diagnostic cytologic criteria; and when reclassifying slides, cytopathologists make a number of false-negative diagnoses.

Adenocarcinoma↗

PubMed1998

The utility of histological examination of tissue removed during elective joint replacement. A preliminary assessment.

The utility of histological examination of tissue removed during elective joint replacement has not been determined. During a one-year period, tissue removed during 168 total joint replacements was submitted for histological examination. The clinical and histological diagnoses, the cost of the histological study, and the clinical course were determined for all joints. Degenerative joint disease, rheumatoid arthritis, and avascular necrosis accounted for 98 per cent of the histological diagnoses. There were sixteen discrepancies between the clinical and histological diagnoses. The histological diagnosis did not affect the treatment of fifteen of these joints. However, the treatment was altered for one joint that had a clinical diagnosis of degenerative joint disease and a histological diagnosis of osteomyelitis; on review, the initial histological diagnosis was determined to be incorrect. In 1996 dollars, the cost of histological examination for all 168 joints was $10,698.24. Although there would be considerable cost-savings on a population basis if histological examination were not performed, this savings must be weighed against the effect of a misdiagnosis on the management of a particular patient.

Adult↗

PubMed1998

Cost-benefit value of microscopic examination of intervertebral discs.

OBJECT: Given the virtual absence of histologically detected, clinically unsuspected disease in intervertebral disc specimens, some authors have advocated that histological examination be discontinued. However, the examination of intervertebral disc specimens remains common practice in most pathology laboratories. No cost-benefit analysis of this practice has been made; therefore, the authors' goal in this study was perform such an analysis. METHODS: Using the University of Iowa surgical pathology database, 1109 patients who had undergone a laminectomy were identified retrospectively. These cases were classified into four categories based on the patients' preoperative clinical diagnosis and final histopathological diagnosis: insignificant clinical diagnosis/insignificant pathological diagnosis (ICIP), significant clinical diagnosis/insignificant pathological diagnosis (SCIP), significant clinical diagnosis/significant pathological diagnosis (SCSP), and insignificant clinical diagnosis/significant pathological diagnosis (ICSP). A significant clinical diagnosis was defined as one other than a benign, noninfectious indication for laminectomy. A significant pathological diagnosis was a diagnosis other than degenerative changes. The cost-benefit value of performing a histological examination in cases with significant or insignificant clinical diagnoses was examined. The cases were classified as: 1068 ICIP, 17 SCIP, 21 SCSP, and three ICSP. On chart review, in all three cases of ICSP an epidural abscess was identified perioperatively and the subsequent histological diagnosis did not affect patient care. The costs per case of identifying a significant pathological diagnosis with a significant and an insignificant clinical diagnosis were $44.79 and $8811, respectively. CONCLUSIONS: Histological examination of intervertebral disc specimens is cost beneficial only if there is a significant preoperative clinical diagnosis.

Abscess↗

PubMed1998

The utility of parotid gland and level I and II neck fine-needle aspiration.

OBJECTIVE: Although fine-needle aspiration (FNA) commonly is used in the diagnostic workup of parotid gland and level I and II neck lesions, the effect of an FNA service on patient care has not been definitively established. METHODS: Follow-up was obtained in 158 patients who underwent FNA. The value of FNA was analyzed by determining the proportions of cases in which management was altered by the information obtained. RESULT: The percentage of lesions classified by FNA as benign, nonneoplastic; benign, neoplastic; atypical or suspicious; malignant; and insufficient was 42%, 28%, 16%, 41%, and 7%, respectively. By using FNA, an operation was avoided in 70% and 79% of patients with a nonneoplastic lesion and a metastasis, respectively. CONCLUSIONS: Although definitive subclassification of some lesion types was poor, FNA was useful in patient triage.

Adolescent↗

PubMed1997

Atypical glandular cells of undetermined significance. Diagnostic accuracy and interobserver variability using select cytologic criteria.

Histologic follow-up of patients with the Bethesda system cervical-vaginal diagnosis of atypical glandular cells of undetermined significance (AGUS), "favor endocervical origin", or "not otherwise specified" (NOS) shows a high percentage of clinically significant (neoplastic or preneoplastic) lesions. Using the criteria of atypical single cells, irregular nuclear membranes, and decreased cytoplasm, eight observers retrospectively reclassified 88 AGUS, "favor endocervical", or NOS smears using a probabilistic scheme. Follow-up showed 46 clinically significant and 42 benign lesions. The mean accuracy for all observers and the experienced observers was 65% and 72%, respectively. For the experienced observers, the mean specificity of a "favor clinically significant" category was 72%; the mean sensitivity of a "favor benign" category was 90%. For the less experienced observers, subclassification had poor predictive value. We conclude that experienced observers may use specific criteria to correctly subclassify AGUS lesions, and this may aid in patient management.

Female↗

PubMed1997

Value-based pathology: a cost-benefit analysis of the examination of routine and nonroutine tonsil and adenoid specimens.

To study the cost-effectiveness of the histologic examination of tonsil and adenoid specimens, the histologic diagnoses for all routine (2,700) and nonroutine (71) tonsil and adenoid specimens during a 10-year period were reviewed. There were 27 routine cases (1%) and 56 nonroutine cases (79%) with a diagnosis other than normal, tonsillitis, or hyperplasia. Twelve of the 27 routine cases did not have a significant clinical history, and a potentially significant pathologic diagnosis was made in only 6 cases; in none of these cases did the pathologic diagnosis affect patient care. In all nonroutine cases, the pathologic diagnosis affected patient care. The average charge per case to detect potentially significant disease in routine and nonroutine cases was $64,718 and $525, respectively. We conclude that histologic examination of nonroutine cases is cost-effective, whereas in most routine cases with adequate clinical history, histologic examination is not cost-effective.

Adenoidectomy↗

PubMed1997

The cost-effectiveness of cervical-vaginal rescreening.

Although most laboratories practice 10% manual rescreening, the cost-effectiveness of this and other rescreening strategies rarely has been evaluated. Using data obtained from the medical literature, a decision model was created in which rescreening strategies were compared with nonrescreening strategies for the number of false-negative and false-positive diagnoses, cancers, life expectancy, and cost-effectiveness. The strategy of 10% rescreening with a repeated cervical-vaginal smear yielded almost no gain in life expectancy compared with an equivalent strategy with no rescreening. With 100% rescreening, the gain in life expectancy was only 0.24 days per patient. A 100% rescreening strategy generally was more cost-effective than a no-rescreening strategy at costs of rescreening varying from $2 to $10 per patient. A 10% rescreening strategy has limited utility. In addition, 100% rescreening strategies are more cost-effective than nonrescreening strategies, but only if the rescreening cost is low.

Adult↗

PubMed1997

The effect of a patient's risk-taking attitude on the cost effectiveness of testing strategies in the evaluation of pulmonary lesions.

STUDY OBJECTIVES: To assess the health and cost effects of a patient's risk-taking attitudes about diagnostic tests. DESIGN: Cost-effectiveness analysis. SETTING: Diagnostic testing strategies used in the evaluation of a patient with a radiographically detected lung lesion were evaluated. Strategies included combinations of sputum, fine-needle aspiration, bronchoscopy, thoracoscopy, and expectant management. PATIENTS: Patient data were obtained from the Survival Epidemiology and End Results Program, MEDLINE search, National Center for Health Statistics, and the Universities of Iowa and Stanford, and Kaiser Permanente Hospital. INTERVENTIONS: Different patient risk-taking attitudes were simulated using decision analysis. MEASUREMENTS: Lifetime cost of medical care, life expectancy, and cost effectiveness. RESULTS: The cost effectiveness of competing strategies depended on patient attitudes about taking risks. For a patient averse to expectantly waiting without definitive knowledge of whether cancer was or was not present, testing strategies using invasive procedures, such as thoracoscopy, were more cost effective. In contrast, for a patient who was identical except that he or she was averse to tests with higher morbidity and mortality, strategies that involved expectantly waiting, instead of more invasive tests, were more cost effective. Small changes in some risk-taking attitudes resulted in large changes in cost effectiveness. CONCLUSIONS: Risk-taking attitudes influenced the cost effectiveness of testing strategies. Consideration of patient risk-taking attitudes in diagnostic testing appears warranted in setting clinical policies and making individual decisions.

Attitude to Health↗

PubMed1997

The importance of sputum cytology in the diagnosis of lung cancer: a cost-effectiveness analysis.

STUDY OBJECTIVE: To assess the potential health and cost effects of initial testing with sputum cytology to diagnose lung cancer. DESIGN: Cost-effectiveness analysis. DATA SOURCES: Surveillance Epidemiology and End Results (SEER) program; cost data from Northern California Kaiser Permanente Hospitals and Universities of Stanford and Iowa; National Center for Health Statistics; and a MEDLINE search. INTERVENTIONS: The use of sputum cytologies preceding other tests (ie, fine-needle aspiration, bronchoscopy, thoracoscopy) in patients with suspected lung cancer. MAIN OUTCOME MEASURES: Mortality associated with testing and initial surgical treatment (eg, performance of thoracoscopy to remove a local-stage, centrally located cancer), cost of testing and initial treatment, life expectancy, lifetime cost of medical care, and cost-effectiveness. RESULTS: In central lesions, sputum cytology as the first test was the dominant strategy because it both lowers medical-care costs ($2,516 per patient) and lowers the mortality risk (19 deaths in 100,000 patients) of the evaluation without adversely affecting long-term survival. In peripheral lesions, sputum cytology costs less then $25,000 per year of life saved if the pretest probability of cancer exceeds 50%. The estimated annual savings of adopting sputum cytology as the first test for diagnosing lung cancer in the United States is at least $30 million. CONCLUSIONS: Experience in regional centers indicates that sputum cytologic testing is infrequently ordered before implementing invasive diagnostic techniques, even in patients with central lung masses. The study findings suggest that sputum cytology as the first test in suspected lung cancer is likely to be cost saving without adversely affecting patient outcomes.

Biopsy, Needle↗

PubMed1997

p53, proliferating cell nuclear antigen, and Ki-67 expression in extrauterine leiomyosarcomas.

Extrauterine leiomyosarcomas, because of their relative rarity, are poorly understood in regards to their malignant potential and biologic markers. Many human tumors are characterized by overexpression of p53, a tumor suppressor protein, and by expression of nuclear proteins associated with proliferation, such as proliferating cell nuclear antigen (PCNA) and Ki-67. We examined expression of these markers in 44 extrauterine leiomyosarcomas from 10 men and 25 women who ranged in age from 25 to 82 years (mean, 56 yr). Clinical follow-up was obtained in 34 (97%) of 35 patients, p53 expression was studied with two monoclonal antibodies (1801, D07) by use of an antigen retrieval method. p53 overexpression was present in 19 (43%) of 44 cases, whereas Ki-67 and PCNA staining were seen in 29 (66%) and 36 (82%) of 44 cases, respectively. There was no correlation between overall survival or recurrence and p53 or PCNA and Ki-67 expression. We conclude that p53, Ki-67, and PCNA are expressed in a large number of extrauterine leiomyosarcomas. In this study, the expression of these markers did not predict biologic behavior.

Adolescent↗

PubMed1997

Telepathologic review: utility, diagnostic accuracy, and interobserver variability on a difficult case consultation service.

The diagnostic accuracy of telepathologic analysis has not been compared to that of conventional light microscopic review on a difficult case consultation service. The anatomic pathology consultation files of the University of Iowa were retrospectively examined, and 105 difficult cases from a variety of organs were chosen for real-time telepathologic and light microscopic review. The telepathologic and light microscopic crude agreement of five pathologists were compared, with use of the original consultation diagnosis as the "gold standard." Cases were scored as correct, partially correct, or incorrect. After making a video diagnosis, the pathologists reported whether they wanted to review the case with use of a light microscope. The pathologists performed significantly better with the light microscope, even after excluding cases in areas of inexpertise (P = .005). The mean percentage of cases that the pathologists wanted to review with the light microscope was 64%, and the major reason for review was diagnostic uncertainty. Cases incorrectly diagnosed with use of the video monitor were almost always requested for review. We conclude that, on a difficult case consultation service, pathologists perform significantly better with use of light microscopic than with telepathologic analysis; rarely make an incorrect diagnosis and do not request that case for light microscopic review; and exhibit high telepathologic diagnostic accuracy in areas of expertise.

Adolescent↗

PubMed1997

Diagnostic accuracy and key cytologic features of high-grade transitional cell carcinoma in the upper urinary tract.

This study examined the diagnostic accuracy of upper urinary tract cytology and defined key cytologic criteria by logistic regression analysis for the diagnosis of high-grade transitional cell carcinoma (TCC). The upper urinary tract cytologic diagnosis was retrospectively reviewed for 153 patients, and diagnostic accuracy was calculated. Cases were scored for the presence or absence of 32 cytomorphologic criteria, and key features to distinguish high-grade TCC from benign lesions were assessed. There were two false-positive and four false-negative diagnoses of TCC. Likelihood ratios for the diagnoses of benign, atypical, suspicious, and TCC were 0.2, 1.4, 3.9, and 32.8, respectively. Regression analysis showed that the cytologic features of aniso-nucleosis, high nuclear/cytoplasmic ratio, and nuclear overlapping were important in the separation of high-grade TCC from benign lesions. We conclude that by using these criteria, the accuracy of diagnosis of high-grade TCC could be improved.

Carcinoma, Transitional Cell↗

PubMed1997

Sensitivity and cost-effectiveness of fine-needle aspiration with immunocytochemistry in the evaluation of patients with a pulmonary malignancy and a history of cancer.

OBJECTIVE: To determine the sensitivity and cost-effectiveness of transthoracic fine-needle aspiration in the separation of primary from metastatic malignancy. MATERIALS AND METHODS: Eighty-nine malignant pulmonary fine-needle aspirations in patients with a history of cancer were classified retrospectively by light microscopy, comparison with previous material, and immunocytochemistry. Decision analysis compared the cost-effectiveness of fine-needle aspiration, bronchoscopy, and thoracoscopy. RESULTS: Fine-needle aspiration classified 87% of the malignancies as primary (n = 7) or metastatic (n = 70) and 13% as indeterminate. By immunocytochemistry alone, 14 of 18 malignancies were subclassified. Decision analysis showed that pulmonary fine-needle aspiration with select use of thoracoscopy was more cost-effective than either bronchoscopy or thoracoscopy alone in many common clinical scenarios. CONCLUSIONS: Pulmonary fine-needle aspiration with immunocytochemistry is sensitive and cost-effective in subclassifying malignancies in patients with a history of cancer.

Adult↗

PubMed1997

Mucinous tumors of the ovary: interobserver diagnostic variability and utility of sectioning protocols.

OBJECTIVES: To determine the interobserver variability of the subclassification of ovarian mucinous tumors and the utility of different sectioning protocols. METHODS: Six pathologists retrospectively reclassified 73 mucinous tumors (30 adenomas, 22 low malignant potential tumors, and 21 carcinomas). Using probabilities, the accuracy of limited sectioning protocols was compared with that of a one section per centimeter protocol. RESULTS: The mean kappa statistic was 0.56, indicating only good agreement. Although a limited sectioning protocol would result in misdiagnosing cases of stage IA carcinoma as a low malignant potential tumor, the overall prognosis of patients with low malignant potential tumors would not markedly change. The prognosis of a patient with a low malignant potential tumor using limited sectioning was within the prognostic range owing to interobserver variability alone. CONCLUSIONS: We conclude that extensive sectioning of ovarian mucinous tumors has limited benefit.

Adenocarcinoma, Mucinous↗

PubMed1996

Utility of fine-needle aspiration biopsy in solid renal masses.

Renal fine-needle aspiration biopsy (FNAB) is used in several clinical scenarios: in patients with classic radiographic lesions; in non-operable patients with presumed high stage disease; and in patients with radiographic problematic lesions. Although overall, FNAB is a sensitive test, its role in the latter two populations has not been clearly established. To investigate the utility of FNAB in these patients, we retrospectively evaluated 43 renal FNABs in regards to diagnostic accuracy and clinical outcome. FNAB diagnoses were: malignant (36), suspicious (6), and insufficient (1). Our results indicate: 1) renal FNAB is accurate in patients with high stage lesions; 2) FNAB is less accurate in patients with radiographic problematic lesions; 3) the FNAB diagnosis of malignant increases the post-FNAB probability of malignancy, whereas the diagnosis of suspicious decreases the probability; and 4) there is excellent correlation for nuclear grade. We conclude that renal FNAB is useful in evaluating renal masses.

Adenocarcinoma↗

PubMed1996

Cytomorphologic characteristics of thermal injury related to endocervical brushing following loop electrosurgical excision procedure (LEEP).

Loop electrosurgical excision procedure (LEEP) is gaining popularity in the United States as an alternative to other ablative and cone methods of treatment for preneoplastic conditions of the uterine cervix. The major advantage is that it is an outpatient procedure using local anesthesia. Post-LEEP evaluation of the endocervical canal can be accomplished by either endocervical curettage or cytobrush. We reviewed the immediate post-LEEP cytobrushes from 33 patients. Artifact related to the procedure was seen in all cases and included: 1) elongated endocervical cells with cytoplasmic "tails" and streaming nuclei ("taffy pulled"); 2) loose cellular aggregates with coalesced cytoplasm and "hockey stick" nuclei; 3) sheets of cells with frothy cytoplasm and shrunken thumbprinted nuclei; 4) nuclear enlargement; and 5) smudgy nuclear chromatin. The background ranged from bloody coagulum to watery proteinaceous material. Original diagnoses were negative in 25 cases. Eleven (44%) were considered abnormal on review. Of these, four were interpreted as having squamous intraepithelial lesions (SIL), one was atypical squamous cells of undetermined significance (ASCUS), and six had atypical glandular cells of undetermined significance (AGUS). It was not always possible to grade the degree of dysplasia. There was review agreement with 14 negatives, one SIL, one ASCUS, and one unsatisfactory specimen. Three AGUS were upgraded to SIL, and one unsatisfactory specimen was considered atypical on review. In conclusion it is possible to separate artifact from actual pathology on post-LEEP cytobrush specimens. Recognition of the characteristic changes seen on cytologic specimens obtained immediately following diathermy loop treatment will allow accurate identification of true abnormalities.

Adult↗

PubMed1996

Telecytology: diagnostic accuracy in cervical-vaginal smears.

Although cervical-vaginal telecytology is a promising tool, diagnostic accuracy has not been extensively evaluated. The authors examined the accuracy of five cytotechnologists who retrospectively reviewed 50 cervical-vaginal smears using the video monitor, and 2 months later, using the light microscope. Accuracy was expressed in terms of crude agreement with the original diagnosis and number of false positives (FPs) and false negatives (FNs). With a greater than one step difference as discrepant, the group crude agreement using the video monitor and the light microscope was 85.6% and 95.6%, respectively. The group number of FNs and FPs for the light microscope was 8 and 7, respectively, and for the video monitor was 34 and 7, respectively. There was a wide range of individual performance. We conclude that accuracy of telecytology is high, but less than that of light microscopy. The major reason for lower telecytologic accuracy was undercalling dysplasia.

Cytodiagnosis↗

PubMed1996

Low-grade transitional cell carcinoma of the urinary bladder: application of select cytologic criteria to improve diagnostic accuracy [corrected].

The cytologic diagnosis of low-grade transitional cell carcinoma of the bladder is difficult, and the reported sensitivity of a positive diagnosis ranges from 0 to 73%. Using regression analysis, our laboratory previously reported the criteria of increased nuclear/cytoplasmic ratios, irregular nuclear membranes, and cytoplasmic homogeneity as indicative of low-grade transitional cell carcinoma. To examine the validity of these criteria, six observers examined 88 bladder-wash specimens (39 transitional cell carcinomas and 49 benign) and, using the selected criteria, graded each wash for the probability of malignancy. Diagnostic accuracy was measured using the receiver operating characteristic curve and the likelihood ratio. Overall observer accuracy was 76%, the sensitivity of a definitive negative diagnosis was 82%, and the specificity of a definitive positive diagnosis was 96%. We conclude that key cytologic criteria can be learned and effectively applied with high accuracy. Observer variation in diagnostic categories might reflect different confidence levels and probabilities of transitional cell carcinoma.

Carcinoma, Transitional Cell↗