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D C Wilbur

Publications and source records attributed to D C Wilbur.

At least 19 recordsLinked to original sources
PubMed2001

The human false-negative rate of rescreening Pap tests. Measured in a two-arm prospective clinical trial.

BACKGROUND: Routine quality control rescreening often is used to calculate the false-negative rate (FNR) of gynecologic cytology. Theoretic analysis suggests that this is not appropriate, due to the high FNR of rescreening and the inability to actually measure it. The authors sought to determine the FNR of manual rescreening in a large, prospective, two-arm clinical trial using an analytic instrument in the evaluation. METHODS: The results of the Autopap System Clinical Trial, encompassing 25,124 analyzed slides, were reviewed. The false-negative and false-positive rates at various thresholds were determined for routine primary screening, routine rescreening, Autopap primary screening, and Autopap rescreening by using a simple, standard methodology. RESULTS: The FNR of routine manual rescreening at the level of atypical squamous cells of undetermined significance (ASCUS) was 73%, more than 3 times the FNR of primary screening; 11 cases were detected. The FNR of Autopap rescreening was 34%; 80 cases were detected. Routine manual rescreening decreased the laboratory FNR by less than 1%; Autopap rescreening reduced the overall laboratory FNR by 5.7%. At the same time, the false-positive rate for Autopap screening was significantly less than that of routine manual screening at the ASCUS level (4.7% vs. 5.6%; P < 0.0001). Rescreening with the Autopap system remained more sensitive than manual rescreening at the low grade squamous intraepithelial lesions threshold (FNR of 58.8% vs. 100%, respectively), although the number of cases rescreened was low. CONCLUSIONS: Routine manual rescreening cannot be used to calculate the FNR of primary screening. Routine rescreening is an extremely ineffective method to detect error and thereby decrease a laboratory's FNR. The Autopap system is a much more effective way of detecting errors within a laboratory and reduces the laboratory's FNR by greater than 25%.

False Negative Reactions↗
PubMed1999

Detection of high grade squamous intraepithelial lesions and tumors using the AutoPap System: results of a primary screening clinical trial.

BACKGROUND: The AutoPap System for the initial screening and quality control of conventional cervical cytology slides previously has shown superior performance for the detection of abnormal slides of low grade squamous intraepithelial lesions and above. This report presents data regarding the important category of high grade squamous intraepithelial lesions and above (HSIL+). METHODS: All slides were run through a Current Practice (CP) arm of manual screening with 10% random quality control followed by an AutoPap (AP) arm of device initial screening with approximately 25% of slides receiving no further review; 75% received a manual rescreen with AP ranking and QC rescreening of 15% of the top ranking negative manual screen slides was performed. Detection performance for truth-determined HSIL+ cases was compared between the two study arms. Available follow-up biopsy results were correlated for cases determined to be HSIL+. RESULTS: Of 25,124 analyzed slides, 70 slides had truth-determination at the HSIL+ level (67 HSILs, 1 adenocarcinoma in situ, and 2 invasive tumors). The AP arm identified 68 of 70 cases (including both invasive tumors). Neither false-negative HSIL+ was found in the 25% "No Further Review" population. The CP arm identified 65 of 70 cases (missing both invasive tumors). The results showed statistical equivalence between the two arms (P = 0.0129). Biopsy follow-up was available in 27 of 70 HSIL+ cases identified by AP and showed abnormality at some level in 100% of cases. CONCLUSIONS: The AP arm was statistically equivalent and showed numeric superiority to the CP arm for the category of HSIL+. Follow-up data confirmed the true-positive nature of these findings. These results are significant because any overall improvement in the performance of an initial screening device must be paralleled by at least equivalence in the clinically important subset category of HSIL+. Cancer (Cancer Cytopathol)

Adenocarcinoma↗
PubMed1999

AutoPap system detection of infections and benign cellular changes: results from primary screener clinical trials.

Primary screening devices for cervical cytology must show performance data for the detection of infectious organisms and benign cellular changes (BCC) for cytologists who routinely report these findings. The data on infection and BCC from the AutoPap primary screening clinical trials are presented herein. The presence of infectious organisms (candida, trichomonas, shift in bacterial flora, herpes, actinomyces) and BCC were noted in each of the clinical trial arms (current practice, CP; AutoPap-assisted practice, AP). For the purposes of these analyses, a report of infection or BCC from either arm was considered to be "truth." In 25,124 slides analyzed, there were 2,925 cases of infection identified. Of these, CP identified 2,141, and AP identified 1,985. The overall detection results are statistically equivalent. Of 17 cases of actinomyces, CP detected 8, while AP detected 12. Of 1,282 cases of candida, CP detected 983, and AP detected 865. Of 1,375 cases of shift of bacterial flora, CP detected 897, and AP detected 869. Of 14 cases of herpes, CP detected 9, and AP detected 11. Of 343 cases of trichomonas, CP detected 293, and AP detected 275. There were 5,156 cases of BCC identified in the trial. CP detected 3,431, and AP detected 3,276. The detection rates for BCC are statistically equivalent. The results show that the AutoPap-assisted practice for the primary screening of conventional cervical cytology slides is equivalent to the current practice for the detection of cervical infections and benign cellular changes.

Actinomyces↗
PubMed1998

Fine-needle aspiration of the macrofollicular and microfollicular subtypes of the follicular variant of papillary carcinoma of the thyroid.

BACKGROUND: The follicular variant of papillary carcinoma of the thyroid (FVPCT) is being increasingly diagnosed on excised thyroid nodules. However, the fine-needle aspiration (FNA) and intraoperative diagnosis is often that of a follicular neoplasm, especially in papillary carcinomas with a pure or predominantly follicular pattern. The authors undertook this study in an attempt to refine the cytologic criteria for the diagnosis of FVPCT. METHODS: The authors reviewed 16 cases with cytologic diagnoses of FVPCT (9 cases), suspicious for FVPCT (6 cases), or cellular adenomatoid nodule (1 case) based on aspirates stained with Papanicolaou stain or a Giemsa-type stain (Diff-Quik). All cases had been confirmed histologically as pure or predominantly (>80%) FVPCT in 13 cases and as follicular adenoma in 3 cases. Cytologic features evaluated included cellularity, cell arrangement, nuclear features, cytoplasm, and colloid. RESULTS: Twelve of 13 cases of FVPCT were correctly diagnosed cytologically. Features that proved useful in the diagnosis of FVPCT were the concomitant and conspicuous presence of ovoid or pear-shaped nuclei with hypochromasia and nuclear grooves. Soft features included nuclear overlap and eccentric, small nucleoli. Cytoplasmic features were not useful in making this diagnosis. Based on cell arrangement and colloid, it was possible to predict microfollicular and macrofollicular variants. The microfollicular subtype showed rosettes or microfollicles and scant, thick colloid in casts and blobs. The macrofollicular subtype had predominantly sheets or spherules with abundant, thick background colloid. Nuclear pseudoinclusions and psammoma bodies were absent and multinucleated giant cells rarely found. Pitfalls leading to a "false-positive" FVPCT diagnosis included oncocytic adenoma (in 2 cases) and atypical adenoma (in 1 case). A cytologic diagnosis of cellular adenomatoid nodule was made in one case of macrofollicular FVPCT. CONCLUSIONS: The authors present improved cytologic criteria for the diagnosis of pure FVPCT on smears stained with Papanicolaou stain or Diff-Quik, and they elaborate on the clues and pitfalls associated with this diagnosis. The cytologic features of the macrofollicular and microfollicular subtypes of FVPCT are also described.

Adenocarcinoma, Follicular↗
PubMed1998

The cost-effectiveness of fine-needle aspiration cytology and 14-gauge core needle biopsy compared with open surgical biopsy in the diagnosis of breast carcinoma.

BACKGROUND: Judicious utilization of fine-needle aspiration cytology (FNAC) and 14-gauge core needle biopsy (CB) theoretically should result in greater accuracy in breast carcinoma diagnosis and fewer unnecessary open surgical biopsies (OSBs), thus lowering health care costs. METHODS: In 1995 in Rochester, New York, the ratio of open surgical breast biopsies per each verified breast carcinoma (OSB/Ca) in a freestanding breast clinic (EWBC) was compared with the OSB/Ca ratio of all physicians in the remainder of the city. The EWBC differs from all other diagnostic facilities in Rochester in that it routinely performs FNAC and CB. RESULTS: The EWBC recommended 462 OSBs resulting in 310 verified carcinomas, for a OSB/Ca ratio of 1.5. The physicians in the remainder of the city recommended 2036 OSBs resulting in 513 verified carcinomas, for a OSB/Ca ratio of 4.0. If the EWBC OSB/Ca ratio had been identical to the remainder of the city, the number of extra OSBs recommended by the clinic would have been 778, resulting in an additional cost of $1,712,082. When the added cost of the 2594 FNACs ($256,285) and 403 CBs ($252,278) performed by the clinic was subtracted from the $1,712,082, the freestanding breast clinic cost savings was $1,203,519. The lymph node metastasis rate of 19% for the breast carcinomas diagnosed in clinic patients was identical to that of the women with breast carcinoma in the remainder of the city. CONCLUSIONS: Utilization of FNAC and CB allows radiologists to lower their OSB/Ca ratio without sacrificing early detection. In this study, these less expensive procedures result in lowered medical costs for the health care system.

Biopsy, Needle↗
PubMed1998

Automation in cytology: a survey conducted by the New Technology Task Force, Papanicolaou Society of Cytopathology.

Despite the overwhelming interest in the development of several computer based technologies in the last several years, the role of automation in cytology has remained controversial. The potential of these technologies in the reduction of false negative results in pap smears is well recognized. However, there is still remarkable confusion as how to incorporate automation in the routine practice of cytology. This prompted the New Technology Task Force of the George Papanicolaou Society of Cytopathology to design a survey to seek the opinion of those engaged in cervicovaginal cytology screening regarding the value of automation in cytology. In 1996, a ten question survey was sent to 1800 cytopathology laboratories throughout the nation. The response rate was 23% (416/1800). The responders represented laboratories varying from those with less than 5,000 pap smears to those with over 100,000 cases per year. The majority of the responders did not believe that automation is essential for cervicovaginal cytology. This was evidenced by the fact that only 12% of the laboratories were engaged in automated cytology and predominantly used it for quality control measures. The inability of small laboratories to absorb the extra expense involved in the integration of automated cytology in their practice, particularly in the current era of managed care was a major concern. There was also concern about the potential for compromise of patient care by the drive for corporate profits and the dissemination of wrong information to the public and physicians. Suggestions most frequently proposed included appropriate patient and physician education about the merits and pitfalls of the pap smear, and also endorsing an affordable universal fee for pap smears. Rescreening for all pap smears, reassessing the benefits of automation in cytology and development of the standards were other proposals. Partnership with larger cytology laboratories, creation of "cytology consortiums" with shared resources to provide regionalized automated rescreening services were also strongly suggested. This survey clearly indicates the need for further evaluation of automation in cytopathology and a focused attention to various issues surrounding cervicovaginal cytology screening.

Automation↗
PubMed1998

Leiomyosarcoma of the maxillary sinus: CT and MRI findings.

This report describes the CT and MRI appearances of a leiomyosarcoma of the maxillary sinus. CT showed frank bony destruction, no calcification and a low attenuation area within the mass. MRI showed intermediate intensity on T1 weighted images, intermediate to slightly high signal intensity on T2 weighted images and moderate inhomogeneous enhancement. Precise identification of the extent of the tumour, especially of orbital invasion, is of utmost importance because local recurrence is common after the resection of leiomyosarcomas.

Aged↗
PubMed1997

The AutoPap 300 QC System multicenter clinical trials for use in quality control rescreening of cervical smears: I. A prospective intended use study.

BACKGROUND: The AutoPap 300 QC System is an automated device for the analysis of conventionally prepared cervical cytology slides. The AutoPap System selects an enriched population of cases for human quality control (QC) review. The device assigns a score based on the likelihood that a slide is abnormal. Cases are selected for QC rescreening that have scores exceeding a preset threshold corresponding to approximately the top 10% (or greater) of scores. METHODS: AutoPap false-negative detection, compared with a 10% random QC process, was tested in a 6-center clinical evaluation study. At each site, a block of up to 150 consecutive negative slides (including detected false-negative cases) were selected randomly daily. All slides were run on the AutoPap System and rescreened by cytotechnologists for truth determination. The false-negative cases included in the top 10% group selected by AutoPap System then were compared with false-negative detection by the random selection process. RESULTS: Fourteen thousand nine hundred fourteen cases were analyzed. The AutoPap-enriched 10% quality control group contained false-negative cases at rates 3 to 5 times that of the random selection method (P < 0.01). The sensitivity for all false-negative cases was 35% and was 52% for false-negative cases at the level of low grade squamous intraepithelial lesion and higher. CONCLUSIONS: The AutoPap 300 QC System provides the potential for a marked increase in the number of false-negative cervical cytology cases that can be detected on QC rescreening. A significant reduction in laboratory false-negative rates can be expected if this device is utilized in routine practice.

Automation↗
PubMed1997

The AutoPap 300 QC System multicenter clinical trials for use in quality control rescreening of cervical smears: II. Prospective and archival sensitivity studies.

BACKGROUND: The AutoPap 300 QC System is an automated device for the analysis of conventional cervical cytology slides. The AutoPap selects an enriched population of cases for quality control review. These studies evaluated the overall sensitivity of AutoPap device to a wider variety of cytologic abnormalities than could be analyzed in the prospective portion of the clinical trials. METHODS: At five clinical trial sites, positive cases were selected from: 1) archives (historic sensitivity study) or 2) current positive cases (current archive sensitivity study). Cases were analyzed by the AutoPap System along with matched negative cases and stratified into detection deciles by instrument score for each diagnostic category. RESULTS: For the historic sensitivity study, the percentages of cases present within the top 10% instrument scores were as follows: atypical glandular cells of undetermined significance (AGUS): 33.7% (n = 243); low grade squamous intraepithelial lesion (LSIL): 57% (n = 412); high grade squamous intraepithelial lesion (HSIL): 81.6% (n = 385); and carcinoma: 77.7% (n = 139). For the current archive sensitivity study, the percentage of cases within the top 10% of instrument scores were as follows: atypical squamous cells of undetermined significance (ASCUS): 37.6% (n = 205); AGUS: 27.3% (n = 22); LSIL: 53.7% (n = 410); HSIL: 80.7% (n = 202); and carcinoma: 62.5% (n = 8). Sensitivities at higher percentiles proportionately were greater. CONCLUSIONS: The AutoPap 300 QC System is detection sensitive, particularly at the level of LSIL and greater. When coupled with the data from the prospective intended use study, these results provided confirmation of the instrument's ability to enhance the false-negative detection rate significantly when compared with a 10% random case selection process. In addition, high sensitivities to all categories of abnormality suggest the possibility of using such instrumentation as a primary screening device for cervical cytology.

Automation↗
PubMed1997

Improving the diagnostic accuracy of cytologic cerebrospinal fluid examinations in acute lymphoblastic leukemia using high-power microscopy and terminal deoxynucleotidyl transferase determinations.

In patients with acute lymphoblastic leukemia (ALL), cytologic examination of cerebrospinal fluid (CSF) is becoming increasingly important for clinical management. In order to enhance the diagnostic accuracy of CSF cytology results, the value of using terminal deoxynucleotidyl transferase (Tdt) and high-power (1,000x) light microscopy, together with conventional cytologic examination was assessed. In 33 CSF samples from ten multiply examined Tdt-positive ALL patients, original cytologic interpretations were compared to Tdt results. Cytology samples were reviewed by two pathologists (one with hematopathologic expertise). The cases in which cytologic interpretation did not correlate with Tdt result were first reviewed via 1,000x microscopy without knowledge of Tdt result, then re-reviewed with knowledge of Tdt result. Conventional cytology alone diagnosed 64% of cases accurately (Tdt representing the comparative standard). High-power microscopy increased the correlation to 82%. Use of high-power microscopy and knowledge of Tdt result together produced a total of 85% of cases with correlation of results. High-power microscopic examination therefore contributes significantly to the accurate diagnosis of ALL, and knowledge of the Tdt result at the time of cytologic examination produces an additional advantage in providing an objective measure for CSF involvement by leukemia. Using all three methods in conjunction is recommended in order to increase the overall accuracy of CSF examination for the detection of leukemic involvement in ALL patients.

Adolescent↗
PubMed1997

False negatives in focused rescreening of Papanicolaou smears: how frequently are 'abnormal' cells detected in retrospective review of smears preceding cancer or high-grade intraepithelial neoplasia?

The 5-year retrospective rescreening process is an integral part of the cytology laboratory's quality assurance program. Its major role is the identification of errors in screening and/or interpretation that represent rare events and patterns. Recognition of such errors can provide for reorientation and reeducation of cytology personnel, ultimately to improve prospective accuracy. Careful research studies have shown that retrospective rescreening may identify abnormalities on slides diagnosed as negative in more than 50% of cases analyzed. Surveys of actual clinical laboratory programs show detection of abnormalities in significantly lower percentages, generally in the range of 10% to 30%. The majority of cases identified are reclassified in the category of atypical squamous cells of undetermined significance. Cases of identified high-grade squamous intraepithelial lesion are identified as a minority of cases in virtually all laboratories surveyed. In the cases reassessed as high-grade squamous intraepithelial lesion, a common cytologic pattern is that of a few isolated, small, "immature metaplastic," dysplastic cells being present.

False Negative Reactions↗
PubMed1996

Use of thin-layer preparations for gynecologic smears with emphasis on the cytomorphology of high-grade intraepithelial lesions and carcinomas.

Thin-layer (TL) technology can improve the detection rate for squamous lesions of the uterine cervix. Studies to date have under-represented high grade lesions and malignancies. The present study utilized a patient population at high risk for such lesions in order to analyze the performance of TL procedures in this group, and in addition, to assess the similarities and differences in morphologic appearances of specimens prepared by the two methods. Conventional (CS) and thin-layer smears (TLS) were made in parallel from the same specimen. Each slide was examined in a blinded fashion. Diagnoses were compared and morphologic observations made. Two hundred fifty-nine cases were included, of which 32 (12%) were high grade dysplasias (11) or carcinomas (21). Thirty five (14%) were atypical or low grade dysplasias. There was exact correlation between Bethesda classification in 231 cases (89%). Of the 21 carcinomas identified, 19 (91%) were present on each preparation. Two cases of endometrial adenocarcinoma were missed on unsatisfactory or negative TLS. One case of squamous cell carcinoma was called high grade squamous intraepithelial lesion (HGSIL) on TLS while the CS was unsatisfactory. Three cases called atypical glandular cells (AGCUS) on TLS, and negative on CS, showed HGSIL (1) or no lesion (2) on follow-up. Morphologic features of low grade lesions were virtually identical on both preparations. Distinct features were noted on TLS in the high grade lesions. These included smaller appearing nuclear areas, less distinct nuclear chromatin, thicker three-dimensional groupings, and more isolated cells. Such findings were most pronounced in the glandular lesions. With training and experience, these features were easily identified in TL preparations, further documenting the utility of this procedure for use in routine practice.

Carcinoma, Squamous Cell↗
PubMed1996

Quantitative image cytometry of infiltrating ductal carcinoma: comparison with prognostic parameters and reproducibility of histological grade.

Quantitative image cytometry was used to compare 18 parameters relating to ploidy, nuclear area, and chromatin texture to axillary lymph node status, tumor size, and histological grade for 34 infiltrating ductal carcinomas, each of which had been graded independently by each of six surgical pathologists. Zinc formalin-fixed, paraffinembedded tumors were assessed using the Elston and Ellis modification of the Bloom and Richardson histological grading scheme. When axillary lymph node-negative tumors were compared with those involving four or more nodes, % 2 c (diploid) cells, nuclear area, and eight of 12 chromatin texture parameters showed statistically significant differences. Carcinomas < 2 cm had more % 2 c (diploid) cells and fewer % > 4 c (hypertetraploid) cells than larger neoplasms. For tumors having nuclear pleomorphism score two versus those with score three, nuclear area, four of five parameters related to ploidy level, each of five parameters related to run-length matrix features and one of four co-occurrence matrix features showed significant differences. Nearly all of these cytometric parameters also showed significant differences for histological grade and mitotic count, which was strongly correlated with nuclear pleomorphism. In examining the cytometric parameters in relation to the interobserver reproducibility of histological grade and its components, the largest number of statistically significant parameters related to the nonreproducibility of nuclear pleomorphism. The findings indicate that as the grade of infiltrating ductal carcinomas increases, there are fewer % 2 c (diploid) cells and more % > 4 c (hypertetraploid) and % > or = 5 c (polyploid) cells. In addition, the cells of high grade tumors have larger nuclear areas and more small and large dense chromatin clumps, which increase in such number that they tend to join together. When compared with the cytometric parameters, nuclear pleomorphism is the most sensitive component of grade to nonreproducibility.

Breast Neoplasms↗
PubMed1996

The effects of endocervical canal topography, tubal metaplasia, and high canal sampling on the cytologic presentation of nonneoplastic endocervical cells.

Use of new endocervical cytologic sampling devices has correlated with increased numbers of cases showing endocervical "atypia." To ascertain the potential causes, a cytologic and histologic correlative study of the normal endocervical canal was undertaken. Hysterectomy specimens from 25 patients with no history of cervical disease were used. The anterior and posterior endocervical canals were divided into three equal sections. Each of the sections of the anterior canal were sampled cytologically, with the corresponding posterior canal processed for histology. Endocervical gland number, depth, and cellular crowding were most pronounced in the middle third of the canal. Tubal metaplasia (present in 100% of cases) was most prominent in the upper third. The most cellular cytologic samples were obtained from the middle third. "Atypical" endocervical groups were most commonly identified in the upper third. The normal topography of the endocervical canal, with sampling of the upper regions by newly utilized devices, may account for the increase in samples showing cytologic patterns that mimic endocervical neoplasia.

Adenocarcinoma↗