ASC-US and high-risk HPV testing: performance in daily clinical practice

Histopathological outcomes of women with abnormal cervical cytology: a review of literature in Thailand

Cervical cytology remains the principal screening method to detect pre-invasive and invasive cervical lesions. Management of abnormal cervical cytology depends on the risk of encountering a significant cervical lesion or high-grade cervical disease. These risks may vary in different areas across the country. Thus, determining the rate of significant cervical lesion associated with each type of abnormal cervical cytology in each area is of critical importance for designing area-specific management approach. This review was conducted to evaluate the rate of high-grade cervical disease among Thai women with abnormal cervical cytology. A relatively high incidence of underlying significant lesions including invasive disease was demonstrated even in those having only minimal smear abnormality. This baseline information is crucial and must be taken into consideration in management of women with abnormal cytological screening to achieve the goals of comprehensive cervical cancer control in Thailand.

The utility of high-risk HPV testing in the management of women 30 to 64 years of age with low-grade squamous intraepithelial lesions on cervical cytology

INTRODUCTION

The current American Society for Colposcopy and Cervical Pathology guidelines recommend high risk-human papillomavirus testing for patients 30 to 64 years of age with a low-grade squamous intraepithelial lesion on Papanicolaou (Pap) tests. This study presents our experience since the introduction of the new guidelines.

MATERIALS AND METHODS

From September 1, 2013 through August 31, 2014, 20,014 ThinPrep Pap tests were processed, of which 17,989 (90%) were negative, 863 (4.3%) were atypical squamous cells of undetermined significance (ASCUS), and 540 (2.7%) were low-grade squamous intraepithelial lesions (LSIL). Thirty-eight percent of the negative cases, 87% of the ASCUS cases, and 76% of the LSIL cases were processed for high risk-human papillomavirus genotypes. Of the 1,163 patients with a Pap test diagnosis of ASCUS and LSIL, 656 (56%) underwent colposcopic examination and, of those, 240 (37%) had cervical biopsies performed.

RESULTS

In our cohort, 247 (33%) of the 754 ASCUS Pap tests were hr-HPV-positive and 507 (67%) were hr-HPV-negative. Of the 409 LSIL Pap tests, 245 (60%) were hr-HPV-positive and 164 (40%) were hr-HPV-negative. Colposcopy/biopsy follow-up within 3-months of the ThinPrep Pap test showed cervical intraepithelial lesion grade 2/3 lesions in 16% of the hr-HPV-positive ASCUS cases, in 15% of the hr-HPV-positive LSIL cases and in 9% of the hr-HPV-negative LSIL cases.

CONCLUSIONS

This study supports the current management guidelines of colposcopy for women 30 to 64 years of age with hr-HPV-positive ASCUS and LSIL on Pap tests and repeat Pap test with cotesting for women with hr-HPV-negative LSIL.

The interplay of age stratification and HPV testing on the predictive value of ASC-US cytology. Results from the ATHENA HPV study

We have previously shown that human papillomavirus (HPV) genotyping, using the cobas HPV Test (Roche Molecular Systems, Pleasanton, CA), can be used to identify women with atypical squamous cells of undetermined significance (ASC-US) at the highest risk for cervical intraepithelial neoplasia (CIN) grade 2 or worse. We investigated the impact of age stratification on the risk of CIN 2 or worse in women with ASC-US and the performance of HPV genotyping in different age strata. The sensitivity of the cobas HPV Test was 93.3% in the 21- to 29-year-old age group and 67.7% in the 40 years or older group, most likely owing to pathologic misclassification of CIN 2 or worse in older women. The prevalence of CIN 2 or worse in younger women was nearly 4-fold that detected in older women and was predominantly HPV-16-related. Age-specific evaluation of ASC-US cytology in conjunction with HPV genotype status enables more effective risk assessment and could be used in clinical management.

Cytologic regression in women with atypical squamous cells of unknown significance and negative human papillomavirus test

OBJECTIVE

The aim of this study was to investigate the cytologic regression in women with atypical squamous cells of unknown significance and negative high-risk human papillomavirus test.

STUDY DESIGN

The 45 women with atypical squamous cells of unknown significance and negative high-risk human papillomavirus at baseline were analyzed about the cytologic regression during 2 years of follow-up. The cumulative rate of cytologic regression was calculated by Kaplan-Meier curves.

RESULTS

Of 45 women, the cumulative rates were as follows: 55.6% obtained cytologic regression before 6 months, 84.4% by 1 year, and 95.6% at 2 years. Cytologic regression was not influenced by age, menopausal status, and baseline human papillomavirus load. However, the 1-year cumulative regression rate in women with previous cervical lesions was significantly lower than those without (P=.02), even much lower in women with high-grade intraepithelial neoplasia or worse (P=.008).

CONCLUSION

Most women with atypical squamous cells of unknown significance and negative high-risk human papillomavirus could obtain cytologic regression within 2 years. Women with antecedent cervical lesions need longer time to reach this regression.

Follow-up findings for women with human papillomavirus-positive and atypical squamous cells of undetermined significance screening test results in a large women's hospital practice

CONTEXT

Reflex human papillomavirus (HPV) testing has been designated in consensus guidelines as "preferred" for women with atypical squamous cells of undetermined significance (ASC-US) liquid-based cytology (LBC) results, and colposcopy is currently recommended for patients with HPV-positive ASC-US results. Data from large clinical practices using newer screening methods and current cytology terminology are limited.

OBJECTIVES

We analyzed data from patients with ASC-US LBC and positive HPV test results. We also assessed the impact of the presence or absence of an endocervical cell/ transformation zone sample (EC/TZS) on biopsy diagnoses.

DESIGN

The information system of a large women's hospital serving an older-than-average population was searched over a 21-month period between July 1, 2005, and March 31, 2007, for HPV-positive cases interpreted as ASC-US (Bethesda System 2001) using computer-imaged LBC. Histologic diagnoses, patient ages, and presence or absence of an EC/TZS were analyzed. The average follow-up period was 7.5 months.

RESULTS

Among 4273 women with HPV-positive ASC-US results, the cumulative cervical intraepithelial neoplasia 2 or 3 (CIN 2/3) and CIN 1 rates for 2192 women with available biopsies were 5.1% and 43.6%, respectively. Cervical intraepithelial neoplasia 2/3 and CIN 1 rates for women with HPV-positive ASC-US results were not significantly different for women with and without an EC/TZS.

CONCLUSIONS

The risk of CIN 2/3 in the study population was significantly lower than reported in widely cited trial data. Neither presence nor absence of an EC/TZS, nor the age of the patient, had a statistically significant impact on the likelihood of biopsy diagnoses of CIN 2/3 and CIN 1 for patients with HPV-positive ASC-US test results.

Triage of women with equivocal or low-grade cervical cytology results: a meta-analysis of the HPV test positivity rate

Consistent evidence underlines the utility of human papillomavirus (HPV) DNA testing in the management of women with equivocal cervical cytological abnormalities, but not in case of low-grade lesions. We performed a meta-analysis including studies where the high-risk probe of the Hybrid Capture-II is used to triage these two cytological categories. The triage test-positivity rate reflects the colposcopy referral workload.Data were pooled on the HPV test positivity rate in women with atypical squamous cells of undetermined significance (ASCUS/ASC-US) or low-grade squamous intraepithelial lesions (LSIL), derived from different cytological classification systems. The meta-analysis was restricted to studies, published between 1991 and 2007. A random-effect model was applied for meta-analytical pooling and the influence of covariates on the HPV positivity rate was analyzed by meta-regression. The variation by age was assessed within individual studies since age strata were not defined uniformly. On an average, 43% (95% CI: 40–46%) of women with ASCUS/ASC-US were high-risk HPV positive (range 23–74%). In women with LSIL, the pooled positivity rate was 76% (95% CI: 71–81%; range 55–89%). In spite of considerable inter-study heterogeneity, the difference in HPV positivity between the two triage groups was large and highly significant: 32% (95% CI: 27–38%). HPV rates dropped tremendously as age and cutoffs of test positivity increased. Other factors (cytological classification system, country, continent, collection method and year of publication) had no statistically significant impact, except in LSIL triage where HPV positivity was significantly lower in European compared to American studies. Women with LSIL, especially younger women, have high HPV positivity rates suggesting limited utility of reflex HPV triaging these cases. Research is needed to identify more specific methods to triage women with low-grade squamous cervical lesions.

Resolution of equivocal results with the Hybrid Capture II high-risk HPV DNA test: a cytologic/histologic review of 191 cases

INTRODUCTION

The Hybrid Capture II (HC II, Digene) high-risk human papilloma virus (HPV) (hrHPV) DNA test is an in vitro nucleic acid hybridization assay that uses enhanced chemiluminescence for the qualitative and semiquantitative detection of hrHPV in cervical samples. Patient samples are concomitantly tested with positive and negative DNA controls and results reported as positive or negative on the basis of a ratio of relative light units to a cutoff value derived from the positive control (RLU/CO). Samples with a ratio <1.0 RLU/CO are expressed as negative for hrHPV, samples with a ratio >2.5 RLU/CO are expressed as positive for hrHPV, and samples with a ratio between these numbers are submitted for retesting. These "equivocal" values are resulted as positive for hrHPV if either of 2 subsequent test values equals or exceeds 1.0 RLU/CO. Samples that show <1.0 RLU/CO after 2 repeat tests are resulted as negative for hrHPV.

METHODS

In this study, we evaluated all hrHPV test results over a 17-month period in our institution. Initial tests showing an equivocal result were analyzed for final retesting result, and for all corresponding and subsequent cytology and histology results. All hrHPV tests were conducted on SurePath (TriPath) or ThinPrep (Cytyc) cervical cytology specimens using the HC II hrHPV DNA test. Subsequent hrHPV tests also were correlated with incident and follow-up findings.

RESULTS

A total of 4792 hrHPV test results were evaluated. Of these, 191 (4%) showed equivocal initial results. When retested, 178 of the 191 samples (93%) resulted positive for hrHPV on first retest and an additional 8 resulted positive for hrHPV on the second retest, bringing the total positive tests to 186 out of 191 (97.4%). Five samples (2.6%) out of 191 were finally expressed as negative for hrHPV. Corresponding cytologic interpretations for the 191 specimens were as follows: NILM-30, atypical squamous cell of undetermined significance (ASC-US)-138, atypical squamous cells--cannot exclude HSIL-13 (ASC-H-13), LSIL-9, and high-grade squamous intraepithelial lesion (HSIL)-1. Follow-up histology was available for 60 of the 191 equivocal cases and showed cervical intraepithelial neoplasia (CIN) II or CIN III in 7 cases, CIN I in 13 cases, and negative or reactive changes in 40 cases.

CONCLUSIONS

On the basis of the results, repeat testing of equivocal specimens might not be necessary as these specimens are overwhelmingly found to be positive for hrHPV. Additionally, hrHPV tests falling in the equivocal range should be considered as definite positive tests, as follow-up results in this cohort demonstrate that significant histologic abnormalities are associated with 10.5% of these cases (20/191), and with 33% of those biopsied (20/60) cases.