An Analysis of Quality Control in Pap Cytology in A Tertiary Care Centre By Using ASC to SIL Ratio

  • Hemalatha J "ESIC Medical College & Postgraduate Institute of Medical Sciences and Research, Rajaji Nagar, Bangalore"
  • Deepak Kumar B "ESIC Medical College & Postgraduate Institute of Medical Sciences and Research, Rajaji Nagar, Bangalore"
  • Srinivasa Murthy V "ESIC Medical College & Postgraduate Institute of Medical Sciences and Research, Rajaji Nagar, Bangalore"
  • Vani BR "ESIC Medical College & Postgraduate Institute of Medical Sciences and Research, Rajaji Nagar, Bangalore"
Keywords: Atypical squamous cells, Squamous intraepithelial lesion, Quality control

Abstract

Background: Atypical Squamous Cells (ASC) is a common gynaecological cytologic abnormality, comprising around 5% of Papanicolaou test results. It reflects a diagnosis of uncertainty and is used as an intra-laboratory & inter-laboratory comparison tool for quality control purposes. For this purpose, ASC/SIL ratio can be used as a quality control measure. Bethesda system suggests that ASC/SIL ratio for an individual or laboratory should be less than 2:1 or 3:1.Objectives:To assess the ratio of ASC/SIL categories and thereby evaluation of quality control in gynaecological cytology smears.Methods: The present study being a retrospective study was conducted in the Dept. of Pathology, ESIC Medical College& Postgraduate Institute of Medical Sciences and Research, (ESIC MC & PGIMSR), Rajajinagar, Bangalore. Archived cases of preceding 5 years from Jan 2012 to Nov 2016 were taken. The clinical details were retrieved from records. The study included conventional pap stained smears of ASC-US, ASC-H, LSIL, HSIL and SCC. A total of 436 cases were studied. ASC/SIL ratio was calculated. ASC component included ASC-US and ASC-H. SIL component included LSIL, HSIL and SCC.Results: Of the total 436 cases, 226 cases were ASCUS and ASC-H and 210 cases were LSIL,HSIL and SCC. ASC/SIL ratio was obtained by dividing the sum of all ASC cases by the sum of all SIL cases. The ratio obtained was 1.1:1 which is below the upper bench mark of 3:1.Conclusion: Monitoring the ASC/SIL ratio of a laboratory is a useful quality control measure.Bethesda system have suggested that the ratio should be less than 3 and others have suggested that lower ratios are desirable. As diagnosis of ASCUS conveys uncertainty, a low ratio decreases the uncertainty produced by laboratory and may reduce the percentage of women with negative biopsy results. DOI: 10.21276/APALM.1421

Author Biographies

Hemalatha J, "ESIC Medical College & Postgraduate Institute of Medical Sciences and Research, Rajaji Nagar, Bangalore"
Department of Pathology, Post graduate student
Deepak Kumar B, "ESIC Medical College & Postgraduate Institute of Medical Sciences and Research, Rajaji Nagar, Bangalore"
Department of Pathology,  Associate Professor
Srinivasa Murthy V, "ESIC Medical College & Postgraduate Institute of Medical Sciences and Research, Rajaji Nagar, Bangalore"
Department of Pathology,  Professor and Head
Vani BR, "ESIC Medical College & Postgraduate Institute of Medical Sciences and Research, Rajaji Nagar, Bangalore"
Department of Pathology, Associate Professor

References

1. Sreedevi A, Javed R, Dinesh A. Epidemiology of cervical cancer with special focus on India. Int J Women's Health. 2015;7:405-414.
2. Krieger PA, McGoogan E, Voojis GP, Amma NS, Cochand- Priollet B et al. Quality Assurance / Control issues. ActaCytologica. 1998;42:133-140.
3. Tobias AHG, Amarlal RG, Diniz EM, Carneiro CM.Quality Indicators of Cervical Cytopathology Tests in the Public Service in Minas Gerais, Brazil. Rev Bras GinecObst.2016;38:65–70.
4. Azara CZS, Manrique EJC, Alves de Souza NL, Rodrigues AR, Nascimento Tavares SBD. Quality Control of Cervical Cytopathology: Interlaboratory Variability. Acta Cytologica.2013;57:585–590.
5. Bibbo M, Wilbur DC ; Comprehensive Cytopathology. 3 rd ed. Saunders: Elsevier; 2008.
6. Auger M. Selection of Monitoring Parameters for Gynecologic Cytology—Beacons of Light for Quality Assurance. Cancer Cytopathology 2014; DOI: 10.1002/cncy.21349
7. Renshaw AA, Deschênes M, Auger M. ASC/SIL Ratio for Cytotechnologists: A Surrogate Marker of Screening Sensitivity. Am J ClinPathol. 2009;131:776-81.
8. Nascimento AF, Cibas ES. The ASC/SIL ratio for Cytopathologists as a Quality Control Measure: A Follow-up Study. Am J ClinPathol. 2007;128:653-56.
9. Ko V, Nanji S, Tambouret R H, Wilbur D C. Testing for HPV as an Objective Measure for Quality Assurance in Gynecologic Cytology Positive Rates in Equivocal and Abnormal Spec imens and Comparison With the ASCUS to SIL Ratio. Cancer Cytopathology 2007;111(2):67-73.
10. Davey DD, Naryshkin S, Nielsen ML, Kline TS. Atypical squamous cells of undetermined significance: interlaboratory comparison and quality assurance monitors. DiagnCytopathol. 1994;11:390–96.
11. Juskevicius R, Zou KH, Cibas ES. An analysis of factors that influence the ASCUS/SIL ratio of pathologists.Am J ClinPathol. 2001;116:331-35.
12. Renshaw AA, Genest DR, Cibas ES. Should Atypical Squamous Cells of Undetermined Significance (ASCUS) Be Subcategorized?: Accuracy Analysis of Papanicolaou Smears Using Receiver Operating Characteristic Curves and Implications for the ASCUS/Squamous Intraepithelial Lesion Ratio. Am J ClinPathol. 2001;116:692-95.
13.Nayar R, Wilbur DC. The Bethesda System for Reporting Cervical Cytology. Definitions, Criteria, and Explanatory Notes. 3 rd ed. New York: Springer; 2015.
14. Davey DD, Woodhouse S, Styer P, et al. Atypical epithelial cells and specimen adequacy: current laboratory practices of participants in the College of American Pathologists Interlaboratory Comparison Program in Cervicovaginal Cytology. Arch Pathol Lab Med. 2000;124:203-11.
15. Davey DD, Nielsen ML, Naryshkin S, et al. Atypical squamous cells of undetermined significance: current laboratory practices of participants in the College of American Pathologists Interlaboratory Comparison Program in Cervicovaginal Cytology. Arch Pathol Lab Med. 1996;120:440-44.
16. Catteau X,Simon P, Noel J C. Evaluation of the Oncogenic Human Papillomavirus DNA Test with Liquid-Based Cytology in Primary Cervical Cancer Screening and the Importance of the ASC/SIL Ratio: A Belgian Study.ISRN Obstetrics and Gynecology 2014; http://dx.doi.org/10.1155/2014/536495.
Published
2017-08-31
Section
Original Article