Inter observer variability in the interpretation of atypical squamous cells in Pap smear examination

Year : 2019 | Volume : 7 | Issue : 1 Page : 59-62

Deepthi V S¹, Ramaswamy AS², Prashant B Mahalingashetti³

¹Assistant Professor, Department of Pathology, PES Institute of Medical Sciences and Research, Kuppam, Andhra Pradesh²Professor and Head, Department of Pathology, PES Institute of Medical Sciences and Research, Kuppam, Andhra Pradesh³Associate Professor, Karwar Institute of Medical Sciences, Karnataka

Address for correspondence: Dr Deepthi V S, Assistant Professor, Department of Pathology, PES Institute of Medical Sciences and Research, Kuppam, Andhra Pradesh

Email: deepthireddyv5@gmail.com

Abstract

Introduction: The incidence of cervical cancer has decreased due to wide spread use of Papanicolaou test (Pap) as a screening method to detect early cervical lesions. According to The Bethesda System 2001, atypical squamous cells are divided into two groups: Atypical squamous cells of undetermined significance (ASC-US), atypical squamous cells cannot exclude HSIL (ASC-H). As it is known, the microscopic interpretation of cytologic specimens is a subjective procedure highly dependent on skills and experience of the investigator. ASC reflects a diagnosis of uncertainty and is used as tool to measure interlaboratory and intralaboratory control for quality control purposes.

Aims and Objectives: To determine the inter observer variation in interpreting ASC variants in conventional pap smears based on the Bethesda system of reporting cervical cytology (2001).

Materials and Methods :A total of 833 cervical smears were sent for Pap test during the period July 2013 to –June 2014. Slides of all the cases of ASC and appropriate number of smears diagnosed as negative for intraepithelial lesion or malignancy were collected with relevant history. An observational study was performed with two evaluators blinded to the original reports. The review reports from the evaluators were compared with original reports to detect accuracy of reporting atypical squamous cells.

Results:Review of data showed 36 low-grade squamous intraepithelial lesion (LSIL), 8 high-grade squamous intraepithelial lesion (HSIL) and 17 cases coded as atypical squamous cells (ASCUS and ASC-H). ASCUS/SIL ratio was 0.33. All the agreements were found out to be statistically significant and the agreement between original diagnosis and observer 1 was found out to be stronger compared to others. Conclusion: Interobserver reproducibility in reporting cervical smears according to Bethesda system 2001 is not 100%, even after following strict Bethesda guidelines. Rescreening of smears is one of the best ways to improve quality control of the cytopathology laboratory.

Keywords::Pap smear, ASCUS, cervix