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Stephen S Raab

Publications and source records attributed to Stephen S Raab.

49 records · Page 3Linked to original sources
PubMed2002

Utility of intraoperative consultation touch preparations.

Although intraoperative touch preparations (TPs) often are performed in conjunction with frozen sections, the comfort level of using TPs in actual practice and the effect of TP quality and cytologic experience on diagnostic accuracy have not been measured. To investigate the utility of intraoperative TPs and to compare them with that of frozen sections, five pathologists of differing levels of cytologic experience retrospectively reviewed 122 intraoperative TPs and frozen sections. Accuracy rates for individual pathologists were calculated and the accuracy using TPs was compared to that of frozen sections. TP accuracy was correlated with TP quality and cytologic experience. The mean rates of correct, incorrect, and atypical TP diagnoses were 88.5%, 4.1%, and 7.4%, respectively. The mean rates of correct, incorrect, and deferred frozen section diagnoses were 86.1%, 2.5%, and 11.9%, respectively. For the four pathologists with cytologic experience, both TP and frozen section diagnostic accuracy rates were similar; however, the pathologist who lacked cytologic experience had lower TP diagnostic accuracy. All pathologists who had cytologic experience requested a frozen section for cases with an atypical or incorrect TP diagnosis. In cases with a correct TP diagnosis a frozen section was requested 46.3% of the time. TPs of greater technical quality were associated with higher diagnostic accuracy. In conclusion, the use of performing TP and frozen section are complementary and result in increased diagnostic accuracy. For some pathologists, TPs may replace frozen sections in over 50% of cases.

Adult↗
PubMed2002

Detection of estrogen receptor by immunohistochemistry in pulmonary adenocarcinoma.

BACKGROUND: The distinction between primary adenocarcinoma and metastatic breast carcinoma in the lung is important for therapeutic purposes. There is a good deal of morphologic overlap between primary pulmonary adenocarcinoma and breast carcinoma metastatic in the lung. Many diagnosticians rely upon the presence of estrogen receptor (ER) in tumors of the lung in women in order to make a pathologic diagnosis of metastatic breast carcinoma. There are conflicting data in the literature regarding the presence of ER in lung carcinomas. In this study, we examined primary lung adenocarcinomas with monoclonal antibodies to two different clones to ER (clone 6F11 and clone 1D5), and progesterone receptor by the immunoperoxidase method in order to ascertain if ER is detectable in primary lung adenocarcinomas. METHODS: Twenty-five resected solitary pulmonary nonmucinous bronchioalveolar carcinomas (15 female, 10 male) and 20 resected solitary pulmonary adenocarcinomas of no special type (12F, 8 mol/L) were studied by the immunohistochemical method using heat-induced epitope retrieval. Immunostaining was semiquantitated, and positive results included nuclear staining for ER and progesterone receptor. All of these tumors were documented as primary pulmonary adenocarcinomas clinically and pathologically. RESULTS: Nuclear ER was seen only with the 6F11 clone, in 56% of the bronchioalveolar type and 80% of the no special type. No nuclear ER was seen in carcinomas utilizing the 1D5 clone. There was no progesterone receptor detectable in carcinomas. CONCLUSIONS: Estrogen receptor is present in the majority of lung adenocarcinomas, and detection of ER in lung adenocarcinomas is dependent upon the antibody clone that is used. Epitope recognition may account for the differences in immunoreactivity between these two antibodies, although a cross-reactive antibody reaction cannot be completely excluded. Further study is warranted to discern the nature of the 6F11 clone immunoreactivity with nuclei of lung adenocarcinomas. The clinical significance and ramifications of ER in pulmonary adenocarcinomas remain unknown. Caution should be exercised by clinicians and pathologists in accepting a diagnosis of metastatic breast carcinoma in lung based on the presence of ER detected by clone 6F11.

Adenocarcinoma↗
PubMed2002

Prognostic value of immunohistochemical expressions of p53, HER-2/neu, and bcl-2 in stage I non-small-cell lung cancer.

The outcomes of patients with stage I non-small-cell lung cancer (NSCLC) vary greatly, with a 5-year survival rate of approximately 60%. This study evaluated a number of molecular markers that may aid in predicting prognosis in stage I NSCLC after surgical resection. Immunohistochemical (IHC) staining of p53, HER-2/neu, bcl-2 proteins was performed on paraffin-embedded sections from 85 stage I NSCLC patients who underwent surgery and were followed up for 32 to 44 (median, 39.0; mean, 37.1) months postoperatively. Differences in survival rates were evaluated by log rank test. The prevalence of p53, HER-2/neu, and bcl-2 expression in stage I NSCLC is 59%, 29%, and 46%, respectively. HER-2/neu expression is seen more frequently in adenocarcinomas, and bcl-2 is seen more frequently in squamous carcinomas. p53 and HER-2/neu expression in stage I NSCLC is associated with significantly short survival. Patients whose tumors were both p53 and HER-2/neu positive had the worst outcome, with a survival rate of only 20%, compared with 80% in those whose tumors were both p53 and HER-2/neu negative (P = .0003). The survival rates were 54% in patients who were p53 positive but HER-2/neu negative and 50% in those who were in p53 negative, HER-2/neu positive. The differences among these 4 groups were statistically significant (P =.001). Bcl-2 does not seem to be a prognostic factor for survival. Multivariate analysis showed that overexpression of p53 and HER-2/neu, presence of angiolymphatic invasion, and tumor size > 3.0 cm were independent factors predicting poor survival. p53 and HER-2/neu by IHC staining appear to be valuable prognostic markers in stage I NSCLC patients after surgery. The worst outcome was seen in patients who expressed both p53 and HER-2/neu, suggesting that these patients might benefit from additional adjuvant therapy.

Adenocarcinoma↗
PubMed2002

Cytohistologic discrepancies: a means to improve pathology practice and patient outcomes.

The use of cytohistologic discrepancies to investigate and reduce error seldom is studied. All gynecologic discrepancies (n = 283; 0.87% and 7.37% of all cytologic and histologic cases, respectively) and nongynecologic discrepancies (n = 146; 2.26% and 0.44% of all cytologic and histologic cases, respectively) for 26 months were classified as sampling or interpretive. Specimen type and pathologist discrepancy percentages, effect of discrepancies on patient outcome, and interobserver agreement of discrepancies were evaluated. Discrepancies were interpretive in 67% and 34% of gynecologic and nongynecologic cases, respectively. Statistically significant associations were seen between individual pathologist and discrepancy percentages. Breast (1.2%) and bronchial (0.8%) cytologic diagnoses had the highest discrepancy percentages. The kappa scores ranged from 0.02 to 0.45 for pairwise agreement of discrepant cases. Of nongynecologic interpretive discrepancies available for review, 63% (27/43) and 14% (6/43) were of no or minor clinical significance, respectively. Cytohistologic correlation is a useful tool to monitor performance and to identify specimen types prone to error.

Biopsy↗
PubMed2002

Papanicolaou tests diagnosed as atypical by a cytotechnologist and downgraded to benign by a pathologist: a measure of laboratory quality.

Follow-up of Papanicolaou (Pap) tests diagnosed as atypical squamous cells of undetermined significance (ASCUS) or atypical glandular cells of undetermined significance (AGUS) by a cytotechnologist and downgraded to benign by a pathologist has not been measured. Squamous intraepithelial lesion (SIL) follow-up rates were obtained for Pap tests diagnosed as ASCUS (288) or AGUS (94) and downgraded to benign and for Pap tests diagnosed as repair (231). Statistically significant associations were seen between 7 cytotechnologists and between 7 pathologists and ASCUS, AGUS, downgraded ASCUS, and downgraded AGUS rates. The percentage of downgraded ASCUS cases compared with all ASCUS cases per pathologist ranged from 4.8% to 43.7%. Statistically significant associations between pathologists and SIL follow-up rates for downgraded ASCUS diagnoses were seen. The SIL follow-up rate for repair (7.9%) was similar to that for a downgraded ASCUS (11.0%) or AGUS (7.3%). The parameters of downgraded ASCU and AGUS Pap test interpretations are good quality indicators of individual performance and overall laboratory quality.

Cell Biology↗
PubMed2002

Willingness to pay for new Papanicolaou test technologies.

The amount of money a woman is willing to pay for liquid-based cytology technology has not been measured. In the present study, 175 women answered a questionnaire asking how much they would pay to decrease their risk of dying of cervical cancer if a new (liquid-based) Papanicolaou (Pap) test was used in place of the conventional smear. When women assumed that the new Pap test reduced the risk of dying of cervical cancer from 1 in 37,000 to 1 in 50,000, the mean amount they were willing to pay was $237. If women had more than 2 children, they were willing to pay more for the new Pap test than women with 2 or fewer children. These data indicate that liquid-based and conventional Pap tests are undervalued and that cost-effectiveness studies generally have not taken into account the preference of women for new Pap test technologies.

Attitude to Health↗
PubMed2002

Estimation of performance and sequential selection of diagnostic tests in patients with lung lesions suspicious for cancer.

CONTEXT: Measuring variation in clinician test ordering behavior for patients with similar indications is an important focus for quality management and cost containment. OBJECTIVE: To obtain information from physicians and nonphysicians regarding their test-ordering behavior and their knowledge of test performance characteristics for diagnostic tests used to work up patients with lung lesions suspicious for cancer. DESIGN: A self-administered, voluntary, anonymous questionnaire was distributed to 452 multiple-specialty physicians and 500 nonphysicians in academic and private practice in Pennsylvania, Iowa, and North Carolina. Respondents indicated their estimates of test sensitivities for multiple tests used in the diagnosis of lung lesions and provided their test selection strategy for case simulations of patients with solitary lung lesions. Data were analyzed using descriptive statistics and the chi(2) test. RESULTS: The response rate was 11.2%. Both physicians and nonphysicians tended to underestimate the sensitivities of all minimally invasive tests, with the greatest underestimations reported for sputum cytology and transthoracic fine-needle aspiration biopsy. There was marked variation in sequential test selection for all the case simulations and no association between respondent perception of test sensitivity and their selection of first diagnostic test. Overall, the most frequently chosen first diagnostic test was bronchoscopy. CONCLUSIONS: Physicians and nonphysicians tend to underestimate the performance of diagnostic tests used to evaluate solitary lung lesions. However, their misperceptions do not appear to explain the wide variation in test-ordering behavior for patients with lung lesions suspicious for cancer.

Biopsy, Needle↗
PubMed2002

The economic benefit for family/general medicine practices employing physician assistants.

OBJECTIVE: To measure the economic benefit of a family/general medicine physician assistant (PA) practice. STUDY DESIGN: Qualitative description of a model PA practice in a family/general medicine practice office setting, and comparison of the financial productivity of a PA practice with that of a non-PA (physician-only) practice. METHODS: The study site was a family/general medicine practice office in southwestern Pennsylvania. The description of PA practice was obtained through direct observation and semistructured interviews during site visits in 1998. Comparison of site practice characteristics with published national statistics was performed to confirm the site's usefulness as a model practice. Data used for PA productivity analyses were obtained from site visits, interviews, office billing records, office appointment logs, and national organizations. RESULTS: The PA in the model practice had a same-task substitution ratio of 0.86 compared with the supervising physician. The PA was economically beneficial for the practice, with a compensation-to-production ratio of 0.36. Compared with a practice employing a full-time physician, the annual financial differential of a practice employing a full-time PA was $52,592. Sensitivity analyses illustrated the economic benefit of a PA practice in a variety of theoretical family/general medicine practice office settings. CONCLUSIONS: Family/general medicine PAs are of significant economic benefit to practices that employ them.

Cost-Benefit Analysis↗
PubMedDate not supplied

Interobserver variability in the fine needle aspiration biopsy diagnosis of follicular lesions of the thyroid gland.

OBJECTIVE: To study the degree of interobserver variability in the interpretation of fine needle aspiration (FNA) biopsies of the thyroid, specifically in the categorization of follicular lesions (FLs), and to examine the accuracy of FNA diagnosis of FLs with surgical follow-up. STUDY DESIGN: Fifty cases were chosen with surgical follow-up and a cytologic diagnosis of either FL (21) or follicular neoplasms (29). Representative slides were selected for each case and circulated to 4 pathologists for review. Interobserver variability was assessed using pairwise K statistics. Accuracy of the cytologic diagnoses in predicting a nonneoplastic or neoplastic outcome was determined by measuring sensitivity and specificity. Likelihood ratios and receiver operator characteristic curves were calculated for each reviewer. RESULTS: Interobserver agreement between the 4 pathologists was fair to substantial (K scores, 0.199-0.617). The accuracy of the 4 pathologists' cytologic diagnoses in predicting the surgical outcome was 77-90% for follicular neoplasms and 53-74% for nonneoplastic diagnoses. CONCLUSION: FLs present diagnostic difficulties as to cytologic categorization. A wide range of interobserver agreement was found in this study of 4 pathologists from the same institution. Some pathologists make greater use of intermediate categories, such as FL, favor nonneoplastic, or FL, favor neoplastic, whereas others show more definitive categorization into benign and neoplastic groups.

Adenocarcinoma, Follicular↗
PubMedDate not supplied

Fine needle aspiration biopsy of vertebral lesions.

OBJECTIVE: To evaluate the accuracy of fine needle aspiration biopsy (FNAB) in the diagnosis of vertebral lesions. STUDY DESIGN: Eighty-nine FNAB cases of vertebral lesions from January 1996 to December 2001 were retrieved from the Allegheny General Hospital laboratory information system. The cases were reviewed and correlated with clinical findings, including previous clinical history, primary site of malignancy and final pathologic diagnosis. RESULTS: ENAB diagnoses were malignant in 43 cases, benign in 35, suspicious in 1, unsatisfactory in 7 and false negative in 3. Previous clinical history included malignancy (37 patients), osteomyelitis and systemic disease (11), and nonspecific or no history (41). In 34 cases (38.2%) both aspirates and core biopsies were available, and the diagnoses correlated in 29/34 cases (85%). Surgical or core biopsies in the unsatisfactory/suspicious group showed malignancy in 4 cases (50%). The sensitivity of FNAB of vertebral lesions was 96%, specificity 100%, positive predictive value 100% and negative predictive value 92%, with no false positive cases. CONCLUSION: FNAB of vertebral lesions is an effective, sensitive and specific procedure in the diagnostic workup of a patient with or without a prior history of malignancy. Surgical pathology examination, including core biopsies of unsatisfactory or suspicious lesions, can further improve the diagnostic yield.

Adolescent↗
PubMedDate not supplied

Atypical glandular cells of undetermined significance favor endometrial origin. Criteria for separating low grade endometrial adenocarcinoma from benign endometrial lesions.

OBJECTIVE: To evaluate cytologic criteria for separating atypical glandular cells of undetermined significance favor endometrial origin (AGUS-EM), on Papanicolaou-stained (Pap) smears into favor benign and favor malignant categories. STUDY DESIGN: All patients who had a Pap smear diagnosis of AGUS-EM, not further qualified, followed by tissue follow-up were identified from the surgical pathology and cytopathology files from January 1992 through December 1996. The Pap smears were scored blindly for the presence or absence of 40 cytologic criteria, and univariate analysis was performed to determine which criteria were most indicative of malignancy by tissue follow-up. RESULTS: The presence of an atrophic smear, nuclear size greater than twice that of an intermediate cell nucleus and absence of clusters with irregular borders were highly indicative of adenocarcinoma, although other criteria were also helpful in identifying malignancy. CONCLUSION: There are no combinations of cytologic criteria that definitely separate AGUS-EM cases into those with benign or malignant findings on follow-up. However, some isolated criteria were useful in the differential diagnosis in a [table: see text] significant number of cases.

Adenocarcinoma↗