Biomedical subjects

Cytopathology Resource Committee, College of American Pathologists

Publications and source records attributed to Cytopathology Resource Committee, College of American Pathologists.

11 recordsLinked to original sources

PubMed2006

Robustness of validation criteria in the College of American Pathologists Interlaboratory Comparison Program in Cervicovaginal Cytology.

CONTEXT: Field validation of slides used in gynecologic cytology proficiency testing has surfaced as an important issue. Although the precision of diagnoses in peer-reviewed educational programs has been examined, the robustness of the validation criteria for specific types of interpretations used in proficiency testing has not been previously studied. OBJECTIVE: To evaluate the robustness of validation criteria for slides entering an educational slide program. DESIGN: We reviewed the results of the College of American Pathologists Interlaboratory Comparison Program in Cervicovaginal Cytology and compared the robustness of validation criteria for different reference diagnoses, using a total of 16,948 circulating slides. RESULTS: Validation criteria could be divided into 2 significantly different groups. The criteria for herpes, Trichomonas, squamous cell carcinoma, and adenocarcinoma were significantly more robust than the diagnoses of unsatisfactory; negative for intraepithelial lesion and malignancy, not otherwise specified; low-grade squamous intraepithelial lesion; and high-grade squamous intraepithelial lesion (P < .001). CONCLUSIONS: The validation criteria used in the College of American Pathologists Interlaboratory Comparison Program in Cervicovaginal Cytology show 2 different levels of robustness or redundancy. These results have implications for the design of fair proficiency tests. Proficiency testing can be designed with the necessary number of reviews needed for slide validation.

Clinical Competence↗

PubMed2006

The significance of certification in liquid-based cytology and performance in the college of american pathologists interlaboratory comparison program in cervicovaginal cytopathology.

CONTEXT: Morphology training and certification provided by the manufacturer is required before laboratories are allowed to prepare and interpret liquid-based cytology (LBC) gynecologic slides. Whether this certification is associated with improved LBC interpretation performance is not known. OBJECTIVE: To determine whether LBC certification correlates with performance. DESIGN: The results of the College of American Pathologists Interlaboratory Comparison Program in Cervicovaginal Cytopathology for the year 2004 were reviewed. During this year a question on the answer form asked participants whether they were certified in LBC preparations. Participant responses were analyzed at 2 levels of agreement with the reference diagnosis of unknown glass slides mailed quarterly. RESULTS: For cytotechnologists and pathologists, participants who were LBC certified had a significantly lower total discordant rate to series than participants who were not certified for validated LBC ThinPrep (Cytyc Corp, Marlborough, Mass) preparations (P < .001 for both groups). The results were similar for validated conventional preparations for pathologists but not for cytotechnologists. The differences were present across most individual diagnostic series. Differences were most striking for low-grade squamous intraepithelial lesions. In addition, cytotechnologists and pathologists who were certified had a significantly lower total discordant rate to the exact diagnosis for validated LBC ThinPrep slides than those who were not certified (discordant rates for cytotechnologists, 14.14% and 23.36%, respectively, P < .001; for pathologists, 15.99% and 24.07%, respectively, P < .001). CONCLUSION: Although not all confounding factors were excluded in this study, LBC certification is associated with a significantly lower discordant rate to both series and exact diagnosis for validated LBC ThinPrep preparations.

Allied Health Personnel↗

PubMed2006

Distinguishing carcinoid tumor of the mediastinum from thymoma: correlating cytologic features and performance in the College of American Pathologists Interlaboratory Comparison Program in Nongynecologic Cytopathology.

CONTEXT: The cytologic features of carcinoid tumor in mediastinal fine-needle aspiration are well described. Nevertheless, this tumor may be difficult to distinguish from thymoma in this site. OBJECTIVE: We sought to correlate the cytologic features of carcinoid tumor of the mediastinum in the College of American Pathologists Interlaboratory Comparison Program in Nongynecologic Cytopathology with the frequency of misclassification as thymoma. DESIGN: We reviewed 446 interpretations from 18 different cases of carcinoid tumor in mediastinum and correlated the cytologic features with performance. RESULTS: Cases were more frequently classified as thymoma (158 responses, 35%) than as carcinoid tumor (126 responses, 28%). The best-performing case was classified as carcinoid tumor only 56% of the time. Three cytologic patterns were identified. Four cases consisted of isolated round cells with salt-and-pepper chromatin. Four cases consisted of isolated spindle and round cells with salt-and-pepper chromatin. The remaining 10 cases consisted of cohesive fragments of crowded cells with finely granular chromatin showing numerous pyknotic cells mimicking lymphocytes. Prominent vasculature patterns were not a feature of any of the cases. There was no correlation between any pattern and the rate of classification as carcinoid tumor or thymoma (P > .05). CONCLUSIONS: Carcinoid tumor of the mediastinum is frequently misclassified as thymoma in this program. Although some cytologic patterns resemble thymoma, the lack of correlation of these patterns with performance suggests that at least part of the reason for misclassification may be failure to consider the correct diagnosis or a lack of familiarity with discriminating cytologic criteria.

Biopsy, Fine-Needle↗

PubMed2006

Leukemia/lymphoma in cerebrospinal fluid: distinguishing between cases that performed well and poorly in the College of American Pathologists Interlaboratory Comparison Program in Non-gynecologic Cytology.

CONTEXT: Although the cytologic features of leukemia/lymphoma in cerebrospinal fluid specimens are well known, the correlation of these features with the ability of cytologists to identify this tumor have not been well studied. OBJECTIVE: To identify the morphologic features of leukemia/lymphoma in cerebrospinal fluid that are associated with good performance and poor performance in an educational interlaboratory comparison program; and to identify the morphologic features associated with how well a slide performs with regard to its reference diagnosis. DESIGN: The performance of 147 cases of leukemia/lymphoma in the College of American Pathologists Interlaboratory Comparison Program in Non-gynecologic Cytology was analyzed. The cytologic features of a subset of 31 cases composed of relatively equal numbers of Romanowsky-stained and Papanicolaou-stained specimens were further evaluated, and those that performed poorly (n = 12) were compared with those that performed extremely well (n = 19). RESULTS: For all cases of leukemia/lymphoma in the program, the rate of misclassification as benign for cases with Papanicolaou stain was significantly higher than for those with Romanowsky stain (9.5% vs 2.6%, P < .001). Compared with cases that performed well, slides that performed poorly were more likely to have less than 200 abnormal cells (42% vs 5%, P = .02). The size of the tumor cells and preservation were not significant. CONCLUSION: Cases of specimens of leukemia/lymphoma in cerebrospinal fluid are more likely to be misdiagnosed as benign if they are Papanicolaou-stained or have 200 abnormal cells.

Cytodiagnosis↗

PubMed2006

Hyperchromatic crowded groups in cervical cytology--differing appearances and interpretations in conventional and ThinPrep preparations: a study from the College of American Pathologists Interlaboratory Comparison Program in Cervicovaginal Cytology.

CONTEXT: The practice of gynecologic cytology requires that high-grade squamous intraepithelial lesion (HSIL) be precisely recognized. In this regard, hyperchromatic crowded groups are known to be difficult to classify in conventional gynecologic cytology, but whether this is true in ThinPrep specimens is uncertain. OBJECTIVE: To assess whether hyperchromatic crowded groups of cells in challenging HSIL cases are a problem in ThinPrep preparations, and whether these groups differ in appearance from those of conventional smears. DESIGN: Sixteen images were taken from both conventional smears and ThinPrep slides that had a reference diagnosis of HSIL in the College of American Pathologists Interlaboratory Comparison Program in Cervicovaginal Cytology, but had performed poorly on subsequent participants' reviews. These 32 representative images were of hyperchromatic crowded groups and were classified by 20 Cytopathology Resource Committee members (17 pathologists and 3 cytotechnologists), who were masked to the reference diagnosis. A consensus classification was derived using the majority opinion of the individual reviewers. Finally, 5 cytologic features were assessed for those images that were interpreted as abnormal by the consensus classification. RESULTS: None of the 32 images was uniformly interpreted as either benign, squamous lesion, or glandular lesion on individual review. Only 27% of individual interpretations of conventional smear images and 15% of ThinPrep images were interpreted as HSIL/squamous cell carcinoma (P < .001). Individual interpretations of ThinPrep images as glandular lesions (60%) were more often made than those of conventional smears (44%, P < .001). The consensus interpretation of ThinPrep images was glandular lesion in 75% of cases, whereas fewer than 50% of the consensus interpretations of conventional smear images were in this category. Conventional smear images were characterized by elongate nuclei (43%) and large nuclei (71%), whereas ThinPrep images more often showed rounded smooth edges (53%) and small nuclei (80%), and were recognized as a glandular lesion. CONCLUSIONS: Hyperchromatic crowded groups of cells are a source of difficulty in challenging HSIL cases for both conventional smears and ThinPrep specimens. In conventional smears, these groups are more likely to be labeled as a squamous lesion, owing to their elongate and large nuclei. In ThinPrep specimens, however, these groups are more likely to be labeled as glandular lesions, owing to their smooth contoured borders and small nuclei.

Carcinoma, Squamous Cell↗

PubMed2005

Measuring the significance of field validation in the College of American Pathologists Interlaboratory Comparison Program in Cervicovaginal Cytology: how good are the experts?

CONTEXT: Expert opinion is often used as a gold standard for gynecologic cytology in the evaluation of new technologies, in the legal setting, and in the validation of cases for use in educational programs and proficiency testing. However, the reliability of expert opinion alone in selecting slides of a specific cytodiagnosis that can be reproducibly and reliably identified by subsequent reviewers has not been determined. OBJECTIVE: To assess the ability of expert opinion to select slides that are validated in subsequent reviews. DESIGN: In the College of American Pathologists Interlaboratory Comparison Program in Cervicovaginal Cytology, each case in every cytodiagnostic category is accepted for circulation only after review by 3 expert cytopathologists. The percentage of these cases that could not be reliably and reproducibly identified by program participants for each cytodiagnostic category ("failed field validation") was determined during the duration of the program from 1989 to 2004. RESULTS: More than 10,000 conventional smears and ThinPrep cases were selected by the expert panel for circulation. Of these selected slides, 19% of conventional smears and 15% of ThinPrep specimens failed field validation. Compared with the overall slide performance, significantly higher percentages (P < .001) of conventional smears with reference diagnoses of unsatisfactory (51.7%), repair (58%), or low-grade intraepithelial lesion (31.8%) and of ThinPrep specimens with reference diagnoses of unsatisfactory (54.5%) and repair (76.9%) failed field validation. In contrast, significantly lower percentages of conventional smears with reference diagnoses of squamous cell carcinoma (4.5%), high-grade squamous intraepithelial lesion (9%), Trichomonas vaginalis infection (11.7%), or herpes (9.9%) and of ThinPrep specimens with reference diagnoses of adenocarcinoma (5.1%), herpes (2.1%), and fungal organism consistent with Candida (8.4%) failed field validation (P < .001 for all). CONCLUSIONS: Between 15% and 19% of gynecologic cytologic cases that have been selected by expert cytopathologists as good examples of cytodiagnostic abnormalities fail field validation. The proportion of cases failing field validation varies with cytodiagnostic category, but it occurs in all cytodiagnostic entities.

Clinical Competence↗

PubMed2005

Measuring the significance of participant evaluation of acceptability of cases in the College of American Pathologists Interlaboratory Comparison Program in cervicovaginal cytology.

CONTEXT: The quality of gynecologic cytology slides within educational and proficiency testing programs may deteriorate during use. Participant evaluation of the acceptability of these slides subsequent to possible deterioration is not known. OBJECTIVE: To assess participants' evaluation of the acceptability of slides circulating within an educational gynecologic cytology glass slide program. DESIGN: The College of American Pathologists Interlaboratory Comparison Program in Cervicovaginal Cytology is a peer comparison and educational program that evaluates the ability of the participants to correctly classify gynecologic cytology preparations. The program uses both expert review and field validation to select slides for the graded portion of the program. Participants were asked to assess the acceptability of slides within the College of American Pathologists Interlaboratory Comparison Program in Cervicovaginal Cytology, and their responses were assessed with respect to type of slide preparation, validation status, and reference diagnosis. In addition, we compared the cytodiagnostic discordancy rates of slides that were deemed acceptable by participants with those that were deemed unacceptable. SETTING: Participant assessments were derived from pathologists and cytotechnologists from cytology laboratories of all types. RESULTS: A total of 17,210 slide interpretations were reviewed, and 2.91% of the cases were labeled unacceptable by participants. For all slides, the percentage of cases called unacceptable varied from 1.65% for cases with a reference interpretation of herpes to 45% for cases with a reference interpretation of unsatisfactory. The percentage of slides deemed unacceptable was higher for validated slides than for educational slides (3.27% vs 2.55%, P = .006). The discordancy rate (to reference diagnosis series) for cases deemed unacceptable was significantly higher than the discordancy rate for cases deemed acceptable for both validated (10.39% vs 1.76%) and educational slides (21.72% vs 3.53%, P < .001). CONCLUSION: Greater than 97% of all slides in the College of American Pathologists Interlaboratory Comparison Program in Cervicovaginal Cytology were judged acceptable by participants. Despite expert review and field validation, a small percentage of slides (almost 3%) in this program were deemed unacceptable by participants. These results support the use of participant evaluation of cases to continually improve the quality of cases in this program.

Clinical Competence↗

PubMed2005

Fine-needle aspiration of pulmonary hamartoma: a common source of false-positive diagnoses in the College of American Pathologists Interlaboratory Comparison Program in Nongynecologic Cytology.

CONTEXT: We use data from the College of American Pathologists Interlaboratory Comparison Program in Nongynecologic Cytology to evaluate the accuracy of fine-needle aspiration (FNA) biopsy for diagnosing pulmonary hamartoma (PH). OBJECTIVE: To use the performance characteristics of the PH cases in the Nongynecologic Cytology Program to determine the accuracy of FNA for identifying these lesions and to determine potential sources of interpretative errors. DESIGN: A retrospective review of the College of American Pathologists Nongynecologic Cytology cumulative data from 1997 to 2003 was performed to identify the overall accuracy of FNA for diagnosing PH and to determine the most common interpretative pitfalls. The slides from each of the cases of PH in the Nongynecologic Cytology Program were then reviewed in an effort to identify the cytologic characteristics that contributed to the poor performance of these cases. RESULTS: A total of 766 participant responses for 19 PH FNA specimens were reviewed. The specificity of FNA for making the correct general reference interpretation of benign was 78%. The false-positive rate was 22%, with the most common false-positive diagnoses being carcinoid tumor, adenocarcinoma, and small cell carcinoma. The overall accuracy for making the correct specific reference diagnosis of PH was 26%. Microscopic review of the individual cases revealed possible explanations for some of the interpretative errors and the most frequent false-positive interpretations. CONCLUSIONS: Cytologists should be aware of the potential false-positive interpretations that can occur in FNAs of PH and the potential reasons for these inaccuracies in order to minimize clinically significant diagnostic errors.

Biopsy, Fine-Needle↗

PubMed2005

Cytologic features of low-grade squamous intraepithelial lesion in thinprep papanicolaou test slides and conventional smears: comparison of cases that performed poorly with those that performed well in the College of American Pathologists Interlaboratory Comparison Program in Cervicovaginal Cytology.

CONTEXT: Both conventional and ThinPrep Papanicolaou smears with high-grade squamous intraepithelial lesions that are frequently missed are known to have relatively few abnormal cells. Whether this is also true of cases of low-grade squamous intraepithelial lesion is not known. OBJECTIVE: To compare the cytologic features of cases of low-grade squamous intraepithelial lesion that perform poorly with the features of cases that perform well. DESIGN: The cytologic features of 10 ThinPrep Pap Test and conventional smear cases of low-grade squamous intraepithelial lesion that performed poorly in the College of American Pathologists Interlaboratory Comparison Program were compared with 46 ThinPrep Pap Test and conventional smear cases that performed extremely well. The numbers of abnormal cells were categorized into less than 50, 51 to 100, 101 to 250, 251 to 500, and more than 500. RESULTS: The median number of abnormal cells for cases that performed poorly was less than 50, whereas the median number of abnormal cells for cases that performed well was between 101 and 250. Overall, cases that performed poorly were significantly more likely to have less than 50, less than 100, and less than 250 abnormal cells than cases that performed well (P < .001, P < .001, and P = .009, respectively). A minority of cases performed well even with very few abnormal cells and groups. The same findings were present when conventional smears and ThinPrep specimens were analyzed separately. CONCLUSIONS: ThinPrep Pap Test cases and conventional smears with a diagnosis of low-grade squamous intraepithelial lesion that perform poorly in this program have significantly fewer abnormal cells than those that perform well. The median number of abnormal cells in cases that performed well is lower than that of comparable high-grade cases in the program.

Carcinoma, Squamous Cell↗

PubMed2005

Pitfalls in salivary gland fine-needle aspiration cytology: lessons from the College of American Pathologists Interlaboratory Comparison Program in Nongynecologic Cytology.

CONTEXT: We use data from the College of American Pathologists Interlaboratory Comparison Program in Nongynecologic Cytology to identify common diagnostic errors in salivary gland fine-needle aspiration (FNA). OBJECTIVE: To identify salivary gland FNA cases with poor performance characteristics in the Nongynecologic Cytology Program surveys, so that the most common diagnostic pitfalls can be avoided. DESIGN: A retrospective review of the College of American Pathologists Nongynecologic Cytology Program's cumulative data from 1999 to 2003 revealed the most common false-positive and false-negative interpretations on FNA for common salivary gland lesions. Slides that performed poorly were then reviewed to identify the cytologic characteristics that may have contributed to their poor performance. RESULTS: A total of 6249 participant responses with general interpretations of benign (n = 4642) or malignant (n= 1607) were reviewed. The sensitivity and specificity of the participant responses for correctly interpreting the cases as benign or malignant were 73% and 91%, respectively. Benign cases with the highest false-positive rates were monomorphic adenoma (53% false-positive), intraparotid lymph node (36%), oncocytoma (18%), and granulomatous sialadenitis (10%). Malignant cases with the highest false-negative rates were lymphoma (57%), acinic cell carcinoma (49%), low-grade mucoepidermoid carcinoma (43%), and adenoid cystic carcinoma (33%). Selected review of the most discordant individual cases revealed possible explanations for some of the interpretative errors. CONCLUSIONS: These data confirm the difficulty associated with interpretation of salivary gland FNA specimens. Cytologists should be aware of the potential false-positive and false-negative interpretations that can occur in FNAs from this organ site in order to minimize the possibility of diagnostic errors.

Biopsy, Fine-Needle↗

PubMed2005

Altered recognition of reparative changes in ThinPrep specimens in the College of American Pathologists Gynecologic Cytology Program.

CONTEXT: Previous studies have shown that the diagnosis of reparative changes in conventional smears in the College of American Pathologists Interlaboratory Comparison Program in Gynecologic Cytology is one of the least reproducible diagnoses. Indeed, the diagnosis of reparative changes consistently yields the highest false-positive rate of any negative for intraepithelial lesions and malignancy (NILM) cytodiagnostic category. It is unknown whether cytologists recognize reparative changes in ThinPrep specimens as well, or less often, as in conventional smears. OBJECTIVE: To assess and compare the ability of cytologists to recognize reparative changes in conventional and ThinPrep preparations. DESIGN: We compiled performance data from the College of American Pathologists Interlaboratory Comparison Program in Gynecologic Cytology from the 2000-2003 program years. More than 400 slides with a reference diagnosis of reparative changes met our study criteria, representing a total of 11 200 individual responses for conventional cases and 1155 individual responses for ThinPrep specimens. We evaluated the results of both individual and laboratory participants using 2 performance criteria: the false-positive discordancy rate and the exact match error rate (any response that does not exactly match the reference diagnosis of 120 [reparative changes]). RESULTS: Cases with a reference diagnosis of reparative changes made up 1.2% of all ThinPrep slides and 3.7% of all conventional slides in circulation. The false-positive discordancy rate of individual responses on educational slides for conventional smears was significantly higher than the corresponding false-positive discordancy rate for ThinPrep specimens (15.7% for conventional vs 7.1% for ThinPrep specimens, P < .001). Laboratory responses on educational conventional smears and ThinPrep slides showed a similar trend (14.2% for conventional smears vs 2.4% for ThinPrep slides, P = .002). The exact match error rate on educational conventional slides was 41.4% for individual responses, while on educational ThinPrep slides, the overall error rate was 57.5% (P < .001). For laboratory responses, the exact match error rate was 40.5% for educational conventional smears versus 58.9% for educational ThinPrep smears (P < .001). Characteristic features of reparative changes were identified in ThinPrep specimens. CONCLUSIONS: In the College of American Pathologists Interlaboratory Comparison Program in Gynecologic Cytology, ThinPrep slides with a reference diagnosis of reparative changes have a lower false-positive discordancy rate than conventional slides. Responses to ThinPrep cases with a reference diagnosis of reparative change show a higher exact match error rate than conventional smears. Since reparative changes in gynecologic cytology are recognized as indicating an increased risk of significant lesions, the clinical significance of these altered patterns of recognition of reparative changes in ThinPrep specimens warrants further investigation.

Cervix Uteri↗