Contribution of human papillomavirus testing by hybrid capture in the triage of women with repeated abnormal pap smears before colposcopy referral

Human Papillomavirus Detection by Hybrid Capture II and Residual or Recurrent High-Grade Squamous Cervical Intraepithelial Neoplasia after Large Loop Excision of the Transformation Zone (LLETZ)

Aims and background

The purpose of this study was to assess the association between highly-oncogenic types HPV DNA detection by Hybrid Capture II (HCII) and residual or recurrent high-grade cervical intraepithelial neoplasia (CIN 2 or 3) during the follow-up of women submitted to large loop excision of the transformation zone (LLETZ).

Study design

In this cohort study, 94 women submitted to LLETZ because of CIN 2 or 3 between March 2001 and September 2002 were followed up twice yearly until September 2003. Follow-up visits consisted of an interview regarding clinical, social and demographic characteristics complemented with gynecological examination with specimen collection for Pap test and HCII and colposcopy. Eighty-one patients attended the first visit (mean 4.8 months, range 3-6) and 75 the second visit (mean 10.9 months, range 7-17 months). McNemar's test to assess the variation of HPV DNA detection following LLETZ, odds ratios (OR) to evaluate the correlation between HPV DNA positivity and residual/recurrent CIN during follow-up, and logistic regression to assess the risk of residual/recurrent CIN were used.

Results

There was a strong and significant reduction in HPV detection after LLETZ ( P <0.001). HPV DNA detection was correlated with residual/recurrent CIN at the first (OR = 103.4; 95% CI 5.5 to 1961.2) and second (OR = 12.7; 95% CI 1.1 to 345.5) follow-up visits. Multivariate analysis showed HPV persistence as a stand-alone risk factor for residual/recurrent CIN (OR = 50.3; 95% CI 3.8 to 663.1).

Conclusions

High risk HPV DNA detection decreased substantially after CIN treatment with LLETZ, but HPV persistence was strongly correlated with residual/recurrent CIN.

High risk HPV testing in the triage of repeat ASC-US and LSIL

INTRODUCTION

The purpose of this study was to evaluate the real-life performance of high-risk (HR) HPV testing in the triage of repeat atypical squamous cells of undetermined significance (ASC-US) and low-grade squamous intraepithelial lesions (LSIL).

MATERIAL AND METHODS

In 2004-2012, 127 women with repeat ASC-US and 118 women with LSIL were triaged with HPV testing using either a Hybrid Capture 2(®) or Abbott RealTime(®) HR-HPV test. The patient charts were retrospectively reviewed for performance of the tests.

RESULTS

In the repeat ASC-US group, 40.9% of the women were positive for HR-HPV. The prevalence of cervical intraepithelial neoplasia grade 2 or worse (CIN2+) was 8.7%. The sensitivity of the HR-HPV testing for detection of CIN2+ was 90.9% (95% Cl 58.7-98.5%), with a specificity of 63.8% (95%CI 54.4-72.5%). In women ≥30 years old, the specificity was 70.4%, whereas in younger women it was only 27.8%. The negative predictive value to predict CIN3 was 100% (95% CI 95.2-100.0%). Of the women with LSIL, 68.6% were positive for HR-HPV and the prevalence of CIN2+ was 14.4%. The sensitivity of HR-HPV testing for detection of CIN2+ was 94.1% (95% CI 71.2-99.0%), and the specificity 35.6% (95% CI 26.4-45.8%), respectively. The negative predictive value to predict CIN3 was 100% (95% CI 90.4-100.0%).

CONCLUSION

HR-HPV testing seems to be beneficial in the triage of repeat ASC-US in women ≥30 years old, but a high prevalence of HR-HPV infection combined with poor specificity limit the use of HPV testing in the case of LSIL.

Human papillomavirus testing versus repeat cytology for triage of minor cytological cervical lesions

BACKGROUND

Atypical squamous cells of undetermined significance (ASCUS) and low-grade squamous intra-epithelial lesions (LSIL) are minor lesions of the cervical epithelium, detectable by cytological examination of cells collected from the surface of the cervix of a woman.Usually, women with ASCUS and LSIL do not have cervical (pre-) cancer, however a substantial proportion of them do have underlying high-grade cervical intra-epithelial neoplasia (CIN, grade 2 or 3) and so are at increased risk for developing cervical cancer. Therefore, accurate triage of women with ASCUS or LSIL is required to identify those who need further management.This review evaluates two ways to triage women with ASCUS or LSIL: repeating the cytological test, and DNA testing for high-risk types of the human papillomavirus (hrHPV) - the main causal factor of cervical cancer.

OBJECTIVES

Main objective To compare the accuracy of hrHPV testing with the Hybrid Capture 2 (HC2) assay against that of repeat cytology for detection of underlying cervical intraepithelial neoplasia of grade 2 or worse (CIN2+) or grade 3 or worse (CIN3+) in women with ASCUS or LSIL. For the HC2 assay, a positive result was defined as proposed by the manufacturer. For repeat cytology, different cut-offs were used to define positivity: Atypical squamous cells of undetermined significance or worse (ASCUS+), low-grade squamous intra-epithelial lesions or worse (LSIL+) or high-grade squamous intra-epithelial lesions or worse (HSIL+).Secondary objective To assess the accuracy of the HC2 assay to detect CIN2+ or CIN3+ in women with ASCUS or LSIL in a larger group of reports of studies that applied hrHPV testing and the reference standard (coloscopy and biopsy), irrespective whether or not repeat cytology was done.

SEARCH METHODS

We made a comprehensive literature search that included the Cochrane Register of Diagnostic Test Accuracy Studies; the Cochrane Central Register of Controlled Trials (CENTRAL) (The Cochrane Library), MEDLINE (through PubMed), and EMBASE (last search 6 January 2011). Selected journals likely to contain relevant papers were handsearched from 1992 to 2010 (December). We also searched CERVIX, the bibliographic database of the Unit of Cancer Epidemiology at the Scientific Institute of Public Health (Brussels, Belgium) which contains more than 20,000 references on cervical cancer.More recent searches, up to December 2012, targeted reports on the accuracy of triage of ASCUS or LSIL with other HPV DNA assays, or HPV RNA assays and other molecular markers. These searches will be used for new Cochrane reviews as well as for updates of the current review.

SELECTION CRITERIA

Studies eligible for inclusion in the review had to include: women presenting with a cervical cytology result of ASCUS or LSIL, who had undergone both HC2 testing and repeat cytology, or HC2 testing alone, and were subsequently subjected to reference standard verification with colposcopy and colposcopy-directed biopsies for histologic verification.

DATA COLLECTION AND ANALYSIS

The review authors independently extracted data from the selected studies, and obtained additional data from report authors.Two groups of meta-analyses were performed: group I concerned triage of women with ASCUS, group II concerned women with LSIL. The bivariate model (METADAS-macro in SAS) was used to assess the absolute accuracy of the triage tests in both groups as well as the differences in accuracy between the triage tests.

MAIN RESULTS

The pooled sensitivity of HC2 was significantly higher than that of repeat cytology at cut-off ASCUS+ to detect CIN2+ in both triage of ASCUS and LSIL (relative sensitivity of 1.27 (95% CI 1.16 to 1.39; P value < 0.0001) and 1.23 (95% CI 1.06 to 1.4; P value 0.007), respectively. In ASCUS triage, the pooled specificity of the triage methods did not differ significantly from each other (relative specificity: 0.99 (95% CI 0.97 to 1.03; P value 0.98)). However, the specificity of HC2 was substantially, and significantly, lower than that of repeat cytology in the triage of LSIL (relative specificity: 0.66 (95% CI 0.58 to 0.75) P value < 0.0001).

AUTHORS' CONCLUSIONS

HPV-triage with HC2 can be recommended to triage women with ASCUS because it has higher accuracy (significantly higher sensitivity, and similar specificity) than repeat cytology. When triaging women with LSIL, an HC2 test yields a significantly higher sensitivity, but a significantly lower specificity, compared to a repeat cytology. Therefore, practice recommendations for management of women with LSIL should be balanced, taking local circumstances into account.

Human papillomavirus triage of women with persistent borderline or mildly dyskaryotic smears: Comparison of costs and side effects of three alternative strategies

The conventional direct referral to colposcopy of persistent borderline or mildly dyskaryotic (BMD) smears in cervical cancer screening leads to considerable unnecessary referrals and associated anxiety and costs. This may be improved by including testing for oncogenic human papillomavirus (HPV) in the triage. We assessed costs and side effects (referrals, treatments and time in follow-up) for 3 possible HPV triage strategies (immediate HPV testing, a 6-month delay in HPV testing, a 2-stage combination of both) and compared them with the conventional strategy. The assessments are based on recent Dutch data from various national databases and trials. We estimated that the referral rate could be reduced by 49, 58 and 58% with immediate, delayed and 2-stage HPV testing, respectively. As a consequence, the average length of follow-up, as well as average costs, also decrease. Therefore, we advocate including HPV testing before referring to colposcopy. Among the 3 HPV strategies, analysis of additional aspects favors implementation of immediate HPV testing.

Role of human papillomavirus DNA testing in management of women with atypical squamous cells of undetermined significance

To find the sensitivity, specificity, and positive and negative predictive values of the high-risk group human papillomavirus (HPV) DNA testing as a triage tool to detect high-grade squamous intraepithelial lesions (HSILs, ie, cervical intraepithelial neoplasia [CIN] 2 or worse) in women with a cytologic smear showing atypical squamous cells of undetermined significance (ASC-US). All new cases with cytologic smears showing ASC-US that presented in King Chulalongkorn Memorial Hospital from January 2003 to November 2003, excluding known cases of HSILs and pregnancies, were enrolled. Cervical cell samplings were done by cervical cytobrush technique and tested for high-risk group HPV with the Hybrid Capture 2 (HC2) test. All participants were examined under a colposcope. Then cervicographs were taken before colposcopic-directed cervical biopsies were done. Of the 90 ASC-US cases enrolled, the pathologic results were normal in 30.0%, squamous metaplasia in 16.7%, CIN 1 in 37.8%, CIN 2 in 1.1%, CIN 3 in 11.1%, and microinvasive cervical carcinoma in 3.3%. The prevalence of HSILs and the prevalence of high-risk HPV detection were 15.6% and 38.9%, respectively. Using pathologic results from cervical biopsy as the gold standard, the HC2 has the sensitivity, specificity, and positive and negative predictive values of 85.7%, 69.7%, 34.3%, and 96.4%, respectively, to detect HSILs. High-risk group HPV detection can be used as an additional triage test to detect HSILs in women having ASC-US with high sensitivity and negative predictive value.

HPV testing in cervical screening

High-risk human papillomavirus (hrHPV) bearing cervical intraepithelial neoplasia (CIN) is considered, as the real precursor lesion of cervical cancer and persistence of an hrHPV infection is necessary for the progression to cervical cancer. This knowledge warrants the use of hrHPV testing as an adjunct to cervical cytology in population-based screening programmes and for monitoring therapy efficacy of high-grade CIN lesions. Replacement of cytology by hrHPV testing altogether is considered, but for this to be (cost-) effective, accurate information about the specificity of the hrHPV test is required. Additional test systems that can be used to stratify women with a positive hrHPV test are HPV genotyping, viral load analysis and hrHPV mRNA analysis. The need for HPV genotyping of cervical smears is illustrated by the increased risk for high-grade cervical lesions associated with HPV types 16 and 18. In particular, for women who have normal but persistently (>1 year) HPV18-positive smears, endocervical curettage is suggested (evidently considering the age and possible future pregnancies of the respective woman) because HPV18 is associated with glandular lesions in the cervix, which are difficult to detect by cytology.

Clinical relevance of human papillomavirus testing in cytopathology

Cancer of the uterine cervix is the second most common cancer in women worldwide. Currently, cervical screening is based on cytology alone. Because infection with high-risk human papillomavirus types (hrHPVs) is a necessary cause of cervical cancer, it has been postulated that screening might become more efficient when it is based on combined cytology and hrHPV testing. In this review we will discuss the advantages of added HPV tests in cervical cancer screening, as a quality control for false-negative smears, in triage of women with equivocal smears, in follow-up of women treated for CIN3 or cervical cancer and for the detection of cervical adenocarcinoma.

Virologic Versus Cytologic Triage of Women With Equivocal Pap Smears: A Meta-analysis of the Accuracy To Detect High-Grade Intraepithelial Neoplasia

BACKGROUND

The appropriate management of women with minor cytologic lesions in their cervix is unclear. We performed a meta-analysis to assess the accuracy of human papillomavirus (HPV) DNA testing as an alternative to repeat cytology in women who had equivocal results on a previous Pap smear.

METHODS

Data were extracted from articles published between 1992 and 2002 that contained results of virologic and cytologic testing followed by colposcopically directed biopsy in women with an index smear showing atypical cells of undetermined significance (ASCUS). Fifteen studies were identified in which HPV triage and the histologic outcome (presence or absence of a cervical intraepithelial neoplasia of grade II or worse [CIN2+]) was documented. Nine, seven, and two studies also documented the accuracy of repeat cytology when the cutoff for abnormal cytology was set at a threshold of ASCUS or worse, low-grade squamous intraepithelial lesion (LSIL) or worse, or high-grade squamous intraepithelial lesion (HSIL) or worse, respectively. Random-effects models were used for pooling of accuracy parameters in case of interstudy heterogeneity. Differences in accuracy were assessed by pooling the ratio of the sensitivity (or specificity) of HPV testing to that of repeat cytology.

RESULTS

The sensitivity and specificity were 84.4% (95% confidence interval [CI] = 77.6% to 91.1%) and 72.9% (95% CI = 62.5% to 83.3%), respectively, for HPV testing overall and 94.8% (95% CI = 92.7% to 96.9%) and 67.3% (95% CI = 58.2% to 76.4%), respectively, for HPV testing in the eight studies that used the Hybrid Capture II assay. Sensitivity and specificity of repeat cytology at a threshold for abnormal cytology of ASCUS or worse was 81.8% (95% CI = 73.5% to 84.3%) and 57.6% (95% CI = 49.5% to 65.7%), respectively. Repeat cytology that used higher cytologic thresholds yielded substantially lower sensitivity but higher specificity than triage with the Hybrid Capture II assay. The ratio of the sensitivity of the Hybrid Capture II assay to that of repeat cytology at a threshold of ASCUS or worse pooled from the four studies that used both triage tests was 1.16 (95% CI = 1.04 to 1.29). The specificity ratio was not statistically different from unity.

CONCLUSION

The published literature indicates that the Hybrid Capture II assay has improved accuracy (higher sensitivity, similar specificity) than the repeat Pap smear using the threshold of ASCUS for an outcome of CIN2+ among women with equivocal cytologic results. The sensitivity of triage at higher cytologic cutoffs is poor.

p16INK4a is a useful marker for the diagnosis of adenocarcinoma of the cervix uteri and its precursors: an immunohistochemical study with immunocytochemical correlations

p16 is a tumor suppressor gene that plays a central role in the regulation of the cell cycle. In squamous cervical cancers, overexpression of p16 is induced by HPV and associated with the carcinogenesis of cervical epithelia. The aim of this study was to determine whether immunostaining of p16 is useful in detecting adenocarcinomas of the cervix uteri in histologic and cytologic routine specimens. A total of 45 surgical specimens, including 18 cases of invasive carcinoma, 8 cases of adenocarcinoma in situ, 4 cases of endocervical glandular atypia (cervical glandular intraepithelial neoplasia), and 15 reactive lesions of the endocervical glands were immunostained using a specific anti-human p16 monoclonal antibody (clone E6H4, mtm laboratories AG, Heidelberg, Germany). Furthermore, immunocytochemical analysis was performed on 10 preoperative ThinPrep cytologic samples with abnormal glandular cells and compared with the human papillomavirus status as assessed with the Hybrid Capture II test. p16 was detected immunohistochemically in all 26 cases of adenocarcinoma of the cervix uteri, including 18 invasive and 8 in situ carcinomas. Only a focal expression was evidenced in the four specimens with endocervical glandular atypia, and no reaction was found in reactive lesions. Also, the immunocytochemical analysis on the 10 ThinPrep specimens evidenced a strong expression of p16 in neoplastic endocervical cells. In all cases this was associated with a high-risk HPV-positive typing. p16 is a useful marker for the detection of the adenocarcinoma of the cervix uteri and its precursors. The immunocytochemical detection on ThinPrep specimens may contribute to an early detection of endocervical lesions.

Evaluation of liquid-based cytology in cervical screening of high-risk populations: a split study of colposcopy and genito-urinary medicine populations

A split study evaluated the ThinPrep(R) PapTesttrade mark (TP; Cytyc Corp., Boxborough, MA) compared with current methodologies of cervical cytology in two high-risk cohorts. One thousand, three hundred cases from a colposcopy clinic and a genito-urinary medicine outpatient clinic were examined. The TP reported increased detection of all grades of dyskaryosis (mild, moderate and severe; + 4.5%) and a decrease in borderline and unsuitable cases (- 4.9%). Four cases of high-grade dyskaryosis (moderate or severe) were detected only using the TP, while an additional four cases classified as high-grade dyskaryosis with the TP were reported as borderline by our conventional methods. The split-study finding of increased sensitivity with the TP provides for improved clinical management of patients in our high-risk cohorts.

Human Papillomavirus Testing and Conventional Pap Smear Cytology as Optional Screening Tools of Women at Different Risks for Cervical Cancer in the Countries of the Former Soviet Union

OBJECTIVES

Human papillomavirus (HPV) infection is a sexually transmitted disease (STD) and the single most important etiological agent of cervical cancer. In parallel with the increase of STDs and because of the lack of any organized cancer screening in the new independent states of the former Soviet Union, the incidence and mortality rates of cervical cancer are rapidly rising. This is the first report from an ongoing European Commission-funded (INCO-Copernicus Program) cross-sectional and cohort study (focused on the key issues of this major health problem in the new independent states) analyzing the performance of the HPV DNA (Hybrid Capture II) test as a potential screening tool for cervical cancer in these countries.

MATERIALS AND METHODS

A series of 3,175 women (screening, gynecological, or STD patients) from six clinics in Russia, Belarus, and Latvia received routine cytology and HPV testing with Hybrid Capture II (HCII). All women with HPV-positive results or abnormalities in cytology were subjected to colposcopy and biopsy. The sensitivity, specificity, receiver operating characteristics, as well as positive (PPV) and negative predicting values (NPV), were determined for HCII and quality-controlled cytology in detecting significant pathology (cervical intraepithelial neoplasia [CIN] 3 and cancer).

RESULTS

Significant pathology was strongly associated with high-grade cytology (odds ratio [OR] = 8.5; 95% confidence interval [CI] = 4.1-17.8; chi-square, p < .0001). Pap smear cytology detected high-grade lesions with a sensitivity of 64.0% (44.8-83.2), specificity of 89.1% (84.5-93.7), PPV of 44.4% (28.8-61.0), and NPV of 94.8% (91.2-98.4). Of the 3,086 samples analyzed by HCII, 33.0% were positive for oncogenic HPV types, with a wide variation (from 23% to 45%) between the three patient groups (p < .0001). The presence of high-grade cytology was significantly associated with HCII positivity at all cutoff levels (OR = 14.4; 95% CI = 8.4-24.5; chi-square, p < .0001; 1 pg/mL threshold). In the receiver operating characteristics curve, the HCII cutoff point most closely balancing sensitivity (83.1%) and specificity (75.6%) was 2 pg/mL. The presence of high-grade histology was associated with HCII positivity (cutoff 1 pg/mL; OR = 4.8; 95% CI = 0.7-34.2;p = .047). At the cutoff (1 pg/mL), sensitivity of the HCII test was 96.6% (90.0-100), specificity was 15.9% (10.6-21.2), PPV was 15.1% (9.9-20.3), and NPV was 96.8% (90.3-100). Changing the cutoff significantly affected sensitivity at 20 pg/mL and NPV at 500 pg/mL.

CONCLUSIONS

HCII assay is a sensitive tool in detecting significant pathology, but less specific than the Pap test. A negative HCII test practically precludes high-grade CIN (NPV, >95%). Because the performance characteristics of the HCII test depend on the prevalence of HPV and CIN in the study population, the cost-benefit issues in different settings will be the limiting factor for the application of this test as a screening tool.