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The Utility of Pap Smears in Anal Dysplasia Screening
S74 initial screening. It is usually misunderstood, miscalculated, and misapplied. An FNP estimated to be 0.05 implies a sensitivity of 0.95, so that 0.05 + 0.95 Z 1.00, or 100 percent accuracy. Published FNPs never include an associated screening sensitivity, and are impossibly low. It can be shown, for example, that FNP 0.05 can be achieved with screening/ rescreening sensitivities of 70%/12.5%, 80%/25%, and 90%/50%. Therefore, the lower the FNP value, the better the screening sensitivity appears to be. This misleading relationship is characterized as a self-reinforcing negative feedback loop. Materials and Methods: Real data can mislead, as it makes screening look better than it is, which can foster complacency and a false sense of confidence. Worse, real data overestimates screening quality, and is used sometimes to justify unjustifiably high cytology workloads. Understanding FNP strengths and limitations is facilitated by using real numbers, not real data. Detecting errors relies on the same method to detect errors that cause the errors in the first place: screening by humans. Results and Conclusions: FNP can be used to estimate the number of undetected false negatives that remain among Pap tests that have been screened once. This paper will be submitted for publication in the new Journal of the American Society of Cytopathology, and will include more information than can be addressed in a platform or poster presentation. 173 The Utility of Pap Smears in Anal Dysplasia Screening Johann Hertel, MD University of North Carolina Chapel Hill, Chapel Hill, North Carolina
Abstracts infections (excluding Pneumocystis jirovecii), however, culture has a lengthy turnaround time. A more timely assessment is possible with cytology and Gomori-methamine silver (GMS) staining. This study examines cytology assessment of fungi with emphasis on diagnostic variances. Materials and Methods: A total of 100 respiratory tract specimens with a positive fungal GMS stain and corresponding culture were selected. The cytology slides were reviewed for factors contributing to discrepant results. Fungi were quantified per 10X ocular field into the following categories: 1-5 organismsZ Scant, 6-10 organismsZ Moderate, and >10 organismsZ High. Specimens were classified into two types of variance: interpretative variance and sampling variance. Concordant diagnoses were also evaluated. Results: Forty-seven of 100 cases had concordant cytology and microbiology results. Variances were both sampling and interpretive (Table 1). Interpretive variance was present in 8 of 100 cases. These cases were predominantly Aspergillus species misinterpreted as Candida. Difficulty identifying true septate hyphae was the major contributing factor for misinterpretation (Figure 1). Sampling variance was present in 45 of 100 cases. A significant number of these cases had scant fungal organisms present (24 of 45 cases, 53%) as compared to the concordant specimens (11 of 47 cases, 23%). The majority of the cases with sampling variance had positive cytology and negative microbiology (39 cases), most likely due to sampling issues or decreased organism viability due to therapy. However, 6 cases had organisms detected on microbiology not found on cytology. Conclusions: Cytologic evaluation of respiratory specimens remains a useful preemptive diagnostic tool in the rapid diagnosis of fungal infection. Interpretive variances between Aspergillus species and Candida organisms are common. Therefore, awareness of the characteristic features which distinguish fungal organisms can further improve the diagnostic utility of cytology. Discrepant results between cytology and microbiology
Introduction: Anal squamous cell carcinoma is a rare disease with an estimated 880 deaths in the United States annually. Though it has a slowly progressive and treatable premalignant phase, due to the incidence, screening is only recommended for high-risk populations. Pap smears, having been effective in cervical screening programs, are being used to screen for anal squamous dysplasia. However, reports have suggested that the Pap smear does not perform as well in anal screening programs. Materials and Methods: In order to evaluate the performance of anal cytology as a screening tool, our electronic database was searched for all anal cytology specimens and all corresponding biopsy specimens. Results: We identified 1525 anal brushings from 849 separate individuals, 203 of which had corresponding anal biopsies. Based on the 203 cases with biopsy correlation, the sensitivity and positive predictive value of anal cytology for all squamous dysplasia and for high-grade squamous intraepithelial lesions (HSIL) was calculated. The sensitivity of anal cytology for all squamous dysplasia is 88% with a positive predictive value of 87%. However, for HSIL the sensitivity is only 25% with a positive predictive value of 67%. Conclusions: The Pap smear is a well-established screening tool for cervical dysplasia and has subsequently been generalized to screening for anal dysplasia in high-risk groups. Our data suggests that the overall sensitivity of anal pap smears for detecting dysplasia is relatively high comparable to the reported sensitivity of cervical pap smears. However, our data also indicates that anal cytology tends to perform poorly in the identification of HSIL. Since current guidelines only recommend treatment for HSIL, the inability to make a distinction between low and high-grade lesions is clinically relevant. As a result, while we are able to identify patients with squamous dysplasia, we are unable to determine whether treatment is required.
Sampling and interpretive variances are listed *Pneumocystis jirovecii was only present on the cytology slides # See Figure 1 for explanation of this case
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Comparison between Fungi Detected on Cytology Specimens and Microbiology Culture: A Review of 100 Cases with Emphasis on Diagnostic Pitfalls
Diagnostic Yield of an Additional Gomori's Methenamine SilverStained Slide for Respiratory Specimens
Suzanne Crumley, MD, April Hull, CT(ASCP), Pat Cernoch, MT, Dina R. Mody, MD, Nour Sneige, MD The Methodist Hospital, Houston, Texas Introduction: Respiratory tract specimens are common in cytology. Microbiology culture is the gold standard for the diagnosis of fungal
Figure 1
Table 1
Examples of fungi identified on cytology
Discrepant results between cytology and microbiology
Sampling Variance Interpretive Variance
Number of Cases
Cytology GMS
Fungal Culture
39 6 6 1 1
Positive Negative* Candida sp. Candida sp. Candida sp.
Negative Positive Aspergillus sp. Coccidiodes immitis# Curvularia luna
April Hull, CT(ASCP), Jaclyn L. Jerz, MD, Suzanne Crumley, MD, Dina R. Mody, MD, Nour Sneige, MD The Methodist Hospital, Houston, Texas Introduction: Respiratory specimens are often stained with Gomori's methenamine silver nitrate (GMS) to highlight microorganisms such as Pneumocystis jirovecii and fungi. We queried whether the number of
Abstracts infections (excluding Pneumocystis jirovecii), however, culture has a lengthy turnaround time. A more timely assessment is possible with cytology and Gomori-methamine silver (GMS) staining. This study examines cytology assessment of fungi with emphasis on diagnostic variances. Materials and Methods: A total of 100 respiratory tract specimens with a positive fungal GMS stain and corresponding culture were selected. The cytology slides were reviewed for factors contributing to discrepant results. Fungi were quantified per 10X ocular field into the following categories: 1-5 organismsZ Scant, 6-10 organismsZ Moderate, and >10 organismsZ High. Specimens were classified into two types of variance: interpretative variance and sampling variance. Concordant diagnoses were also evaluated. Results: Forty-seven of 100 cases had concordant cytology and microbiology results. Variances were both sampling and interpretive (Table 1). Interpretive variance was present in 8 of 100 cases. These cases were predominantly Aspergillus species misinterpreted as Candida. Difficulty identifying true septate hyphae was the major contributing factor for misinterpretation (Figure 1). Sampling variance was present in 45 of 100 cases. A significant number of these cases had scant fungal organisms present (24 of 45 cases, 53%) as compared to the concordant specimens (11 of 47 cases, 23%). The majority of the cases with sampling variance had positive cytology and negative microbiology (39 cases), most likely due to sampling issues or decreased organism viability due to therapy. However, 6 cases had organisms detected on microbiology not found on cytology. Conclusions: Cytologic evaluation of respiratory specimens remains a useful preemptive diagnostic tool in the rapid diagnosis of fungal infection. Interpretive variances between Aspergillus species and Candida organisms are common. Therefore, awareness of the characteristic features which distinguish fungal organisms can further improve the diagnostic utility of cytology. Discrepant results between cytology and microbiology
Introduction: Anal squamous cell carcinoma is a rare disease with an estimated 880 deaths in the United States annually. Though it has a slowly progressive and treatable premalignant phase, due to the incidence, screening is only recommended for high-risk populations. Pap smears, having been effective in cervical screening programs, are being used to screen for anal squamous dysplasia. However, reports have suggested that the Pap smear does not perform as well in anal screening programs. Materials and Methods: In order to evaluate the performance of anal cytology as a screening tool, our electronic database was searched for all anal cytology specimens and all corresponding biopsy specimens. Results: We identified 1525 anal brushings from 849 separate individuals, 203 of which had corresponding anal biopsies. Based on the 203 cases with biopsy correlation, the sensitivity and positive predictive value of anal cytology for all squamous dysplasia and for high-grade squamous intraepithelial lesions (HSIL) was calculated. The sensitivity of anal cytology for all squamous dysplasia is 88% with a positive predictive value of 87%. However, for HSIL the sensitivity is only 25% with a positive predictive value of 67%. Conclusions: The Pap smear is a well-established screening tool for cervical dysplasia and has subsequently been generalized to screening for anal dysplasia in high-risk groups. Our data suggests that the overall sensitivity of anal pap smears for detecting dysplasia is relatively high comparable to the reported sensitivity of cervical pap smears. However, our data also indicates that anal cytology tends to perform poorly in the identification of HSIL. Since current guidelines only recommend treatment for HSIL, the inability to make a distinction between low and high-grade lesions is clinically relevant. As a result, while we are able to identify patients with squamous dysplasia, we are unable to determine whether treatment is required.
Sampling and interpretive variances are listed *Pneumocystis jirovecii was only present on the cytology slides # See Figure 1 for explanation of this case
174
175
Comparison between Fungi Detected on Cytology Specimens and Microbiology Culture: A Review of 100 Cases with Emphasis on Diagnostic Pitfalls
Diagnostic Yield of an Additional Gomori's Methenamine SilverStained Slide for Respiratory Specimens
Suzanne Crumley, MD, April Hull, CT(ASCP), Pat Cernoch, MT, Dina R. Mody, MD, Nour Sneige, MD The Methodist Hospital, Houston, Texas Introduction: Respiratory tract specimens are common in cytology. Microbiology culture is the gold standard for the diagnosis of fungal
Figure 1
Table 1
Examples of fungi identified on cytology
Discrepant results between cytology and microbiology
Sampling Variance Interpretive Variance
Number of Cases
Cytology GMS
Fungal Culture
39 6 6 1 1
Positive Negative* Candida sp. Candida sp. Candida sp.
Negative Positive Aspergillus sp. Coccidiodes immitis# Curvularia luna
April Hull, CT(ASCP), Jaclyn L. Jerz, MD, Suzanne Crumley, MD, Dina R. Mody, MD, Nour Sneige, MD The Methodist Hospital, Houston, Texas Introduction: Respiratory specimens are often stained with Gomori's methenamine silver nitrate (GMS) to highlight microorganisms such as Pneumocystis jirovecii and fungi. We queried whether the number of