Journal of Cytology

ORIGINAL ARTICLE
Year
: 2013  |  Volume : 30  |  Issue : 1  |  Page : 33--35

Evaluation of the category high-grade squamous intraepithelial lesion in The Bethesda System for reporting cervical cytology


Subhalakshmi Mukhopadhyay, Sumit Ray, Supria Dhar, Ranjana Bandyopadhyay, Swapan K Sinha 
 Department of Pathology, Medical College, Kolkata, West Bengal, India

Correspondence Address:
Subhalakshmi Mukhopadhyay
Department of Pathology, Medical College, 88 College Street, Kolkata, West Bengal
India

Abstract

Background: High grade squamous intraepithelial lesion (HSIL) is a category of The Bethesda System (TBS) for reporting cervical cytology that is in vogue since the introduction of the said system in 1988 and it was not modified in 2001 modification of TBS. The term includes moderate dysplasia (CIN II), severe dysplasia (CIN III) and squamous cell carcinoma in situ. Terms like ASC-US used in TBS are being considered to be not very useful in the prediction about the possible behavior of the pathological status of the cervix. After more than 10 years of use the term HSIL also needs fresh evaluation as in this category two entities of potentially different outcome are clubbed. Aims: The aim was to find out whether it is justified to have a term like HSIL which includes different points of the spectrum of intraepithelial pathology of cervix from moderate hyperplasia through carcinoma in situ, all having different significance. Materials and Methods: In this study 619 cases of cervical cytology reported by TBS were evaluated by comparing them with biopsy reports of the same lesion for the assessment of the sensitivity, specificity and positive predictive value of HSIL as a category of diagnosis in TBS. Results: As a category, HSIL had the diagnostic sensitivity of 96.4%, specificity of 87.5%. The positive predictive value was 96.4%. Conclusion: HSIL as a diagnostic category shows a very good predictive accuracy, which implies that it provides a very high probability of the accurate diagnosis collectively of all the conditions in the disease spectrum from moderate dysplasia through in situ carcinoma. Hence, HSIL was found to be a very useful diagnostic category in TBS that conveys proper message to the clinician.



How to cite this article:
Mukhopadhyay S, Ray S, Dhar S, Bandyopadhyay R, Sinha SK. Evaluation of the category high-grade squamous intraepithelial lesion in The Bethesda System for reporting cervical cytology.J Cytol 2013;30:33-35


How to cite this URL:
Mukhopadhyay S, Ray S, Dhar S, Bandyopadhyay R, Sinha SK. Evaluation of the category high-grade squamous intraepithelial lesion in The Bethesda System for reporting cervical cytology. J Cytol [serial online] 2013 [cited 2020 May 31 ];30:33-35
Available from: http://www.jcytol.org/text.asp?2013/30/1/33/107510


Full Text

 Introduction



Cervical cancer is the third most common cancer in women worldwide, with an estimated 529,000 new cases in 2008. [1] More than 85% of the global burden is in developing countries, accounting for 13% of all female cancers. It is the most common cancer in females in India. [1]

High-grade squamous intraepithelial lesion (HSIL) is encountered in about 0.5-4.6% of all cervical Pap samples. [1],[2] Cytological screening for cervical cancer and precancerous conditions has been proved to be very effective in cervical cancer prevention and in lowering mortality. Evaluation for proper categorization of intraepithelial lesions of cervix, some of which are potentially precancerous, is important because patient management planning depends on the category of dysplasia. The new terminologies of The Bethesda System (TBS) for reporting cervical cytology was introduced in the year 2001. It has categories like low grade squamous intraepithelial lesion (LSIL) that represents dysplasia involving the lower one-third of the squamous epithelium and HSIL that includes all dysplastic lesions beyond it. The category HSIL of the current system includes moderate dysplasia (CIN II), severe dysplasia (CIN III) and carcinoma-in situ (CIN III) of the previous systems.

It is now well established that not every entity of the said system is free from its drawback: An example is ASCUS, an entity that has been a waste basket of diagnosis.

HSIL, the entity in The Bethesda System for reporting of cervical carcinoma, therefore encompasses moderate dysplasia, severe dysplasia and carcinoma in situ. [2],[3] Moderate dysplasia needs no tissue diagnosis and prompt action, waiting with careful monitoring is all that is necessary. [3],[4] Severe dysplasia or carcinoma in situ needs quick confirmation by biopsy. Operative removal of the lesion or other specific treatment is urgently required in these cases. This study aims at evaluating the appropriateness of the use of the term HSIL in reporting of cervical cytology after 10 years of the usage of these terms in clinical practice.

The aim of the study was to calculate the positive predictive value of HSIL as a diagnostic category.

 Materials and Methods



In a period of 1 year, 651 consecutive cervical cytology smears were collected in the Department of Gynecology from patients not known to have diagnosis of cervical carcinoma.

These smears were then evaluated in the Department. of Pathology. 32 smears were found to be inadequate (4.77%) and remaining 619 cases were selected. Colposcopy and biopsy was done for confirmation in cases of HSIL and carcinoma cervix. Diagnostic sensitivity, specificity and positive predictive value of categorization as HSIL were calculated by comparing it with histopathology as gold standard.

 Results



A total of 473 smears were without any neoplasia or dysplasia, 302 of which were inflammatory smears without atypia of cells; 146 in all were the group having cancer, atypical squamous cells of undetermined significance (ASCUS), HSIL, LSIL together. The total number of suspected cancer was 16 (2.5%) and HSIL was 56 (9.04%).

HSIL was most prevalent in the 46-50 age-group (21.42%), followed closely by the 41-45 age group. (17.85%). No case was reported as 'atypiacl squamous cells (ASC) - cannot exclude HSIL'.

Biopsy revealed invasive squamous cell carcinoma in 2 cases out of 56 cases of HSIL (3.5%). Severe dysplasia and not invasive cancer was present in 2 out of 16 cases of carcinoma diagnosed by cytology [Table 1]. There was no case of adenocarcinoma in this series.{Table 1}

HSIL as a category had 96.4% diagnostic sensitivity, 87.5% specificity and the positive predictive value was 96.4% [Table 2].{Table 2}

Diagnosis of cervical carcinoma by cytology showed 87.5% sensitivity and 96.4% specificity.

ASC-US was the diagnosis in 26 (4.2%) patients and low-grade squamous intraepithelial lesion (LSIL) was found in 48 cases (7.75%).

A total of 3.9% of ASCUS were later diagnosed as LSIL in two subsequent cytological follow-ups within 6 months time and none as HSIL. The ASC to LSIL ratio was 0.5, which was calculated as a quality control measure.

 Discussion



In this study HSIL was most prevalent in the 46-50 age-group which is younger than other study populations. [4],[5] ASCUS and LSIL cases were low and 5% of smears were inadequate. Higher numbers of HSIL cases and cancer cases were found compared to other studies.

Cyto-histological correlation was obtained in 96.4% of high-grade lesions which was quite high. In a retrospective review of 12,188 conventional cervical smears ASC-US was 19.8%, ASC-H was 8.8%, LSIL was 9.0% and HSIL was 4.6%; squamous cell carcinomas accounted for 0.5%.

The highest rates of HSILs and invasive squamous carcinoma occurred in women aged 50-59 years. [6] Gupta et al. [5] found that 26% of HSIL cases were under diagnosed on cervical smears. In another study by Sodhani et al., [7] cyto-histological correlation was obtained in 77.5% of high-grade lesions.

The Bethesda System for reporting cervical cytology is in vogue since 1988 and it has standardized reporting by and large. It has been proved to be superior to the Papanicolaou system. [8] Even after 10 years since the introduction of the 2001 Bethesda system, providing a specific information that would help the gynecologist in patient management is not an easy task always for the pathologist. Terms like ASC-US or HSIL-H (atypical squamous cells, cannot exclude high-grade squamous intraepithelial lesion) are of significance, although not free from confusion. [5],[6]

The diagnostic category 'HSIL' includes moderate and severe dysplasia or CIN 2 and CIN 3. A special phrase may be added as and when necessary to this term which makes the report a bit confusing 'HSIL-with features suspicious of invasion' because there is another category 'squamous cell carcinoma' in the same system. Apart from this, there is an inherent shortfall of cytology in comparison with biopsy: To diagnose carcinoma, presence of tumor diathesis in the background is the only differentiating feature separating HSIL from carcinoma. In this situation, there is only a thin line of demarcation between HSIL and carcinoma at cytology level and that is why reporting as HSIL may fail to alert the doctor about an in situ cancer or may over report a CIN2. Assessment of usefulness of the category 'HSIL' is therefore important and clinical correlation is very important in every individual case.

In this series the ASC to LSIL ratio was 0.5, which means very good standard of reporting in this series as the ASCUS/SIL ratio has been promoted as a useful quality control measure. It has been suggested by the authors of the Bethesda System that the ASCUS/SIL ratio for an individual or laboratory should be less than 3.0, and others have suggested that lower ratios are desirable. Because the diagnosis of ASCUS conveys uncertainty, a low ratio reduces the uncertainty generated by the laboratory and may reduce the percentage of women with negative biopsy results. [9]

This study proves that in TBS, as a category, the term HSIL is highly sensitive, and its positive predictive value is great [Table 2]. The term is highly effective for use in cervical cytology screening and reporting. HSIL is a cytological category that encompasses biologically different entities like moderate dysplasia and in situ squamous cell carcinoma, with potentially different outcome.

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