Is a liquid-based cytology more sensitive than a conventional Pap smear?

Prevalence of abnormal pap smears in the western region of Saudi Arabia from 2010 to 2022

Objectives

The objectives of the study were to assess the prevalence of abnormal Pap smears and their quality metrics in a tertiary health-care facility in the western region of Saudi Arabia and to share our data with other researchers in Saudi Arabia to potentially establish benchmark data based on a Saudi population.

Material and Methods

A retrospective study was carried out by the Department of Pathology at King Fahd Armed Forces Hospital, Jeddah, Saudi Arabia, on Pap smear statistics for 14,376 Pap smears of both conventional and liquid-based cytology (LBC) between 2010 and 2022.

Results

The prevalence of abnormal Pap smears of both conventional and LBC was 3.05% (438 Pap smears). The percentages of adenocarcinoma and squamous cell carcinoma were 0.08% and 0.02%, respectively, and the ratio of atypical squamous cells (ASCs) to squamous intraepithelial lesions (SILs) (ASC/SIL) was 2.61.

Conclusion

The prevalence of abnormal Pap smears and the ASC/SIL ratio were consistent with the international benchmark data provided by the College of American Pathologists for each preparation type and within the range of the data provided by published studies, highlighting the need for greater focus on glandular abnormalities.

Comparative Analysis of Conventional Cytology and Liquid-Based Cytology in the Detection of Carcinoma Cervix and its Precursor Lesions

Context

The conventional smears (CS) and Liquid based cytology (LBC) are important tools to detect carcinoma cervix and its precursor lesions.

Aims

The present study was done to compare the cytomorphological features of cervical lesions using both techniques and compare with the histopathological diagnosis.

Settings and Design

This was a prospective observational study over a period of 1.5 years at a tertiary care hospital.

Methods and Material

A total of 969 women in the age group of 21-65 years presenting with either routine screening or complaints of vaginal bleeding, discharge, or pelvic pain were enrolled for the study. Both the CS and LBC smears were analyzed and compared with the corresponding histopathology diagnosis. The data was analyzed using Statistical Package for the Social Sciences (SPSS) software and P values <0.05 were considered significant.

Results

There were 8.57% unsatisfactory smears in CS as compared to 0.5% in LBC smears. Liquid-based cytology was superior to conventional preparations in terms of smear adequacy, lesser hemorrhagic and inflammatory background, and presence of more endocervical cells. Liquid-based cytology showed a better yield in detecting all the types of epithelial cell lesions with a concordance rate of 73.9% between the two techniques. On histopathology correlation of these lesions, LBC had a higher sensitivity (96.67%) and diagnostic accuracy (99.08%) as compared to CS (73.33% and 92.66%, respectively).

Conclusions

Liquid-based cytology is superior to conventional cytology for the detection of epithelial cell lesions. Reduction in the unsatisfactory smears, a cleaner background, and better representation of the sample are more significantly appreciated on LBC in contrast to CS.

High-Risk Human Papillomavirus Detection via Cobas® 4800 and REBA HPV-ID® Assays

Persistent infection with high-risk human papillomaviruses (HR-HPVs), particularly HPV16 and 18, has long been known to induce cervical cancer progression. However, given that a minority of HPV-infected women develop cancer, analysis of HR-HPV-infected women could help to predict who is at risk of acquiring cervical cancer. Therefore, to improve HR-HPVs detection, we used the FDA-approved cobas^® 4800 HPV and REBA HPV-ID^® HPV assays to detect HR-HPVs in colposcopy-derived cervical cells from 303 patients, detecting 72.28% (219) and 71.62% (217) of HR-HPVs positive cases, with HPV16 detection rates of 35.64% (108) and 30.69% (93), respectively. Of the HPV16-positive cases, cobas^® 4800 and REBA HPV-ID^® identified 28.81% (51) and 25.42% (45) of the CIN1 cases, and 55% (33) and 50% (30) of the 60 CIN2/3 cases, respectively. HPV-diagnostic concordance was 82.17% overall (kappa = 0.488), 87.45% for HR-HPVs (kappa = 0.689), and 88.33% for CIN2/3 (kappa = 0.51). The HR-HPVs detection rates of these assays were comparable. Our findings reveal that the FDA-approved HR-HPVs detection assay is appropriate for screening women with HR-HPVs infection, and for predicting increased risk of cervical cancer progression. REBA HPV-ID^® can be used to detect low risk-HPV types in high-grade cervical lesions that are HR-HPV negative as well as in the distribution of HPV types.

Liquid-Based Cytology in the Detection of Premalignant Lesions in Patients with "Atypia in Squamous Cells" in Conventional Cytology

Background

The management of patients with "Atypical Squamous Cells" (ASC) in conventional papanicolaou smears (CPS) is based on the risk of high-grade squamous intraepithelial lesion (HSIL). The efficacy of liquid-based cytology (LBC) to detect this premalignant lesion is variable, with little evidence of its performance in Colombian patients.

Aims

The aim of this study is to determine the performance of LBC in the detection of premalignant lesions, in patients with ASC in CPS.

Materials and Methods

Were obtained patients who attended colposcopy clinic due the result of ASC in CPS. An LBC was taken, which was interpreted by two pathologists without access to other results. The performance of LBC to detect HSIL, was determined, considering as a gold standard: histopathological study/negative-satisfactory colposcopy.

Results

Were included 114 patients, with a mean age of 38.4 years (SD ± 13.3). LBC had abnormal results in 40.36% (n = 46), with a slightly higher proportion of low-grade squamous intraepithelial lesion (LSIL) than HSIL. The total of abnormal diagnoses by colposcopy and/or biopsy was 51.75% (n = 59), with a predominance of LSIL (36.84%). The sensitivity of the liquid-based cytology to detect premalignant lesions was 76.5%, specificity: 66.0%, positive predictive value: 28.3% and negative predictive value: 94.1%; The Cohen's kappa index of LBC for detecting HSIL was 0.2492 for the total population and 0.2907 for ≥30 years.

Discussion

Although LBC decreases abnormal cytology and increases the detection of HSIL, which improves diagnostic accuracy; sensitivity and predictive values for detecting HSIL are not significantly different between CPS and LBC.

Comparison of conventional and liquid-based Pap smear methods in the diagnosis of precancerous cervical lesions

Cervical cancer is one of the five most common cancers among women. The present study aimed to compare conventional and liquid-based Pap smear methods in 2018 in Kerman, Iran. This was a cross-sectional study. Pap smear samples (conventional Pap smear (CN) and liquid-based cytology (LBC)) were collected from five health centres in Kerman. Samples were classified into two groups of liquid and CNs, and each group was classified into normal, abnormal (including, atypical squamous cells of undetermined significance (ASCUS⁺), atypical squamous cells, cannot exclude high-grade squamous intraepithelial lesion (ASC-H⁺), low-grade squamous intraepithelial lesion (LSIL⁺), high-grade squamous intraepithelial lesion (HSIL⁺) and cancer⁺) and unsatisfactory. Descriptive data analysis and chi-square/Fisher's exact test were performed in SPSS 20 (SPSS Inc., Chicago, IL). Totally, 31,513 women were screened by two CN and LBC. The mean age of subjects was 39.73 ± 9.58 years. The unsatisfactory smears (1.4% versus 0.02%; p=.001) and ASCUS⁺ (45.1% versus 39.4%; p=.007) were more reported by conventional tests, while LSIL⁺ (33.1% versus 38.9%; p=.005) was reported by the LBC test. Among women who were younger than 40 years, the CIN2⁺ that was found by LBC was significantly more than the CN method (37.4% versus 31.7, p=.04) and among older women (older than 40 years) the CIN1⁺ was significantly more as well (18% versus 13.6%, p=.05). The present study showed that, although LBC had many advantages, CN is still useful. Further studies are to be suggested as a clinical trial in another population with a large number of participants to compare the diagnosing methods of cervical cancers. Impact StatementWhat is already known on this subject? The conventional Pap smear (CN) and liquid-based cytology (LBC) methods are the most common methods for screening cervical cancers. Previously, in some studies, LBC was reported as a better method and in some studies, traditional method was preferred. Conflicting results were found in previous articles.What do the results of this study add? LBC compared to CN could find truer abnormal cases. The superiority of the LBC method is seen in cases such as reducing unsatisfactory cases, etc. LBC compared to CN could find more CIN⁺. Also, LBC could find more CIN1⁺ among women older than 40 years and more CIN⁺ ≥2 among younger women.What are the implications of these findings for clinical practice and/or further research? Although LBC has many advantages and it is easier, CN is still useful and both methods are suitable for cervical abnormality and cancer detection. CN cannot be declared an outdated method.

Cervical cytopathological changes in pregnancy: An experience from a low resource setting

Background:

Cervical cancer is the leading cause of death among women in developing countries. It is preventable through effective cervical cancer screening program. However, in Nigeria, screening programs are opportunistic and coverage is insufficient to make an impact.

Aim:

This study assessed the cervical cytopathological changes among pregnant women at booking using liquid-based cytology (LBC) in Aminu Kano Teaching Hospital (AKTH).

Methodology:

This was a cross-sectional study that was carried out at the antenatal Clinic of AKTH, Kano, Nigeria. A total of 161 pregnant women who fulfilled the criteria and gave their consent were recruited into the study using systematic sampling technique at booking for antenatal care. LBC was employed using standard procedure and samples sent to histopathology department for analysis. Pro forma developed for the study was used to obtain the socio-demographic and reproductive characteristics of the women and the risk factors for abnormal cervical cytology.

Results:

Out of the 161 pregnant women that had cervical cytology screening using LBC on their first prenatal visit during the study, 22 had abnormal cervical cytology, giving a prevalence rate of 13.7%. Out of this, six (27.3%) were atypical squamous cells of undetermined significance, 3 (13.6%) were Atypical Squamous Cells, Cannot Rule Out HSIL (ASC-H), 11 (50.0%) were low-grade Squamous Intraepithelial Lesions while 2 (9.1%) were high grade squamous intraepithelial lesions. Negative smears were seen in 104 women (64.6%). Inflammatory and other conditions of the cervix which are technically negative smears made up the remaining 21.7%. There was a statistically significant association between cervical cytology results and advanced age (P < 0.01), increasing number of lifetime sexual partners since coitarche (P < 0.01), high parity (P < 0.01), absent previous Pap test (P < 0.027), previous history of sexually transmitted infections (P < 0.040), and positive HIV status (P < 0.001). Following binary logistic regression, advanced maternal age, increasing number of sexual partners, high parity, and positive HIV status stood out to be independent predictors of premalignant lesions of the cervix in pregnancy in this study.

Conclusion:

Advanced maternal age, increasing number of sexual partners, high parity, and positive HIV status stood out to be independent predictors of premalignant lesions of the cervix in the study. Routine cervical cytology screening using LBC should be offered to all antenatal clients in our setting to increase coverage and detection rate of preinvasive lesions of the cervix, and/or pregnant women with increased risk of abnormal cervical cytology from this study.

Method for preservation of DNA stability of liquid-based cytology specimens from a lung adenocarcinoma cell line

Liquid-based cytology (LBC) specimens of lung adenocarcinoma have the potential to be widely used for genetic analysis. However, formaldehyde contained in some LBC preservation solutions can cause DNA fragmentation during specimen storage, rendering the samples unsuitable for molecular analysis. To investigate a novel preservation technique for improved DNA stability, which was evaluated by mutation analysis of epidermal growth factor receptor (EGFR) gene in human lung adenocarcinoma cell lines. Cells were fixed in CytoRich Red preservation solution. After 30 min of fixation, cells were either stored using the conventional method (suspended in preservation solution) or washed in phosphate-buffered saline and stored as a cell pellet (newly proposed method). The effect of storage was evaluated after 5, 7, and 9 days of storage at ambient temperature. The cell pellet group was also tested after 14 and 28 days. Specifically, we evaluated the DNA stability, DNA yield, and sample suitability for polymerase chain reaction (PCR), and EGFR mutation detection. The DNA yields and degree of stability from the cell pellet group were higher than those from the suspension group at every time point examined. PCR amplification from the cell pellet group was successful up to day 28. Mutation detection using the Cycleave PCR method indicated that the Ct values of the cell pellet group were significantly lower than those of the suspension group. Storing LBC specimens as a cell pellet post-fixation can maintain the DNA quality for a longer period than the conventional method, making it a promising strategy for molecular analysis.

Cost-Effectiveness and Cost-Benefit of Cervical Cancer Screening with Liquid Based Cytology Compared with Conventional Cytology in Germany

Objective

To assess the health economic impact of cervical screening with liquid based cytology (LBC) compared with conventional cytology (CC) in Germany.

Methods

An economic model was constructed depicting the management of a hypothetical cohort of women aged ≥20 years who undergo cervical screening in Germany. The model estimated the cost-effectiveness and cost-benefit of LBC compared with CC at 2017/18 prices over a time-horizon of 70 years.

Results

Performing cervical screens with LBC instead of CC is expected to increase the probability of detecting a true positive over a subject's lifetime by 73% (0.038 versus 0.022) and of diagnosing a subject with stage 3 cervical intraepithelial neoplasia (CIN3) (0.019 versus 0.011). Women screened with LBC instead of CC are expected to have a 57% reduction in the probability of having undetected CIN3 (0.006 versus 0.014) and to experience a 44% reduction in the probability of transitioning into disease progression (from 0.018 to 0.010). The mean discounted lifetime cost of healthcare resource use associated with performing cervical screens with LBC and CC was estimated at €4852 and €7523 per subject respectively. For every Euro invested in cervical screening with LBC instead of CC, the German healthcare system could potentially save ~€170 over a subject's lifetime.

Conclusion

Within the study's limitations, the analysis showed that LBC affords a cost-effective cervical screening test compared with CC in Germany, since it improves detection rates and has the potential to lead to a reduction in disease progression for less cost.

Diagnostic Test Accuracy Review of Cytology for Squamous Intraepithelial Lesion and Squamous Cell Carcinoma of Uterine Cervix

BACKGROUND

Even though cervico-vaginal smears have been used as a primary screening test for cervical carcinoma, the diagnostic accuracy has been controversial. The present study aimed to evaluate the diagnostic accuracy of cytology for squamous intraepithelial lesion (SIL) and squamous cell carcinoma (SqCC) of the uterine cervix through a diagnostic test accuracy (DTA) review.

METHODS

A DTA review was performed using 38 eligible studies that showed concordance between cytology and histology. In the DTA review, sensitivity, specificity, diagnostic odds ratio (OR), and the area under the curve (AUC) on the summary receiver operating characteristic (SROC) curve were calculated.

RESULTS

In the comparison between abnormal cytology and histology, the pooled sensitivity and specificity were 93.9% (95% confidence interval [CI], 93.7%-94.1%) and 77.6% (95% CI, 77.4-77.8%), respectively. The diagnostic OR and AUC on the SROC curve were 8.90 (95% CI, 5.57-14.23) and 0.8148, respectively. High-grade squamous intraepithelial lesion (HSIL) cytology had a higher sensitivity (97.6%; 95% CI, 94.7%-97.8%) for predicting HSIL or worse histology. In the comparison between SqCC identified on cytology and on histological analysis, the pooled sensitivity and specificity, diagnostic OR, and AUC were 92.7% (95% CI, 87.3%-96.3%), 87.5% (95% CI, 87.2%-87.8%), 865.81 (95% CI, 68.61-10,925.12), and 0.9855, respectively. Geographic locations with well-organized screening programs had higher sensitivity than areas with insufficient screening programs.

CONCLUSION

These results indicate that cytology had a higher sensitivity and specificity for detecting SIL and SqCC of the uterine cervix during primary screening.

Reducing DNA damage by formaldehyde in liquid-based cytology preservation solutions to enable the molecular testing of lung cancer specimens

BACKGROUND

Liquid-based cytology (LBC) is a useful cytopathological method, and LBC lung adenocarcinoma specimens may be used for genetic analysis in the near future. In the current study, the authors determined whether LBC specimens can be used for epidermal growth factor receptor (EGFR) mutation analysis in human lung adenocarcinoma cell lines.

METHODS

Genomic DNA was extracted from 3 lung adenocarcinoma cell lines that were fixed in LBC preservation solution using 2 protocols (one for cultured cells and one for tissues) of a DNA extraction kit. Different fixation times were tested for each protocol: 30 minutes, 1 hour, and 1 to 9 days. As controls, cells also were fixed in 10% formalin or 95% ethanol. The authors investigated the effect of fixation time on DNA fragmentation, polymerase chain reaction (PCR) amplification, and EGFR mutation detection.

RESULTS

The DNA yield of LBC specimens tended to decrease depending on fixation time. When using the DNA extraction protocol for tissues, PCR amplification was successful after 9 days of fixation, although extracted genomic DNA that was fixed for >1 hour demonstrated fragmentation. Mutation analyses using the Cycleave PCR method were successful after 7 days of fixation. The DNA extraction protocol for tissues was appropriate for lung adenocarcinoma cell lines that were stored for >1 day in a preservative solution. The results of the current study demonstrated that EGFR mutations can be detected on day 7 using lung adenocarcinoma cell lines fixed in CytoRich Red preservative.

CONCLUSIONS

When LBC specimens are used for targeted molecular genetic testing, the appropriate preservative solution and extraction protocol first should be determined.

Comparative Analysis of Modified Liquid-Based Cytology and CytoRich Red Preparation in Assessment of Serous Effusion for Cancer Diagnosis

Objective: We aimed to compare the cytomorphological diagnosis in serous effusion and quality of background between modified liquid-based cytology (modified-LBC) and CytoRich Red (CRR) preservative. Methods: We used an experimental study design: 110 fresh serous effusions were received from 50 cases negative for malignant effusions and 60 cases positive for malignant effusions. All fresh serous effusions were processed using both the CRR solution and the modified-LBC preparation. Blind sample slides were interpreted for cytomorphological diagnosis and the quality of background by 2 cytotechnologists. Result: All cases had the same diagnosis irrespective of the method. There was no statistically significant difference in the cytological diagnosis between the CRR and modified-LBC preparations (p>0.999). The quality of the background smear for the CRR preparation was clean (54%), moderate in 42%, and poor in 4%. By comparison, the modified-LBC preparation was clean in 46%, moderate in 47%, and poor in 7%. The difference between the quality of background smears between the two methods was not statistically significant (p= 0.527). Conclusion: There was no statistically significant difference in the diagnosis or quality of background between CRR and modified-LBC preparations. The serous effusion specimen prepared by modified-LBC solution was less expensive than CRR. The modified-LBC could be an alternative preparation when commercial preparations are too expensive.

Cervical Cancer Detection between Conventional and Liquid Based Cervical Cytology: a 6-Year Experience in Northern Bangkok Thailand

Objectives:

To determine the prevalence of abnormal Papanicolaou (Pap) smear, cervical intraepithelial neoplasia (CIN) 2 or higher and cancer between conventional Pap smear (CPP) and liquid based Pap smear (LBP).

Methods:

This retrospective study was conducted at Bhumibol Adulyadej Hospital, Bangkok, Thailand between January 2011 and December 2016. Data was collected from medical records of participants who attended for cervical cancer screening test. Sensitivity, specificity, positive predictive value (PPV), negative predictive value (NPV) and accuracy for detecting CIN 2 or higher were evaluated by using the most severity of histopathology reports.

Results:

A total of 28,564 cases were recruited. Prevalence of abnormal Pap smear from CPP and LBP were 4.8 % (1,092/22,552) and 5.7 % (345/6,012), respectively. Percentage of unsatisfactory smears in CPP (52.3%) was higher than LBP (40.5%). From CPP and LBP, cervical cancer percentages were 0.2 and 0.1, respectively. Sensitivity, specificity, PPV, NPV and accuracy of CPP and LBP for detection cancer were 42.5 vs 26.1%, 99.9 vs 100.0%, 69.8vs 75.0%, 99.7 vs 100.0 % and 99.7 vs 99.7%, respectively.

Conclusion:

Prevalence of abnormal cervical cytology and cancer from CPP and LBP were 4.8/0.2 and 5.7/0.1 percent, respectively. Unsatisfactory smear of LBP was less than CPP. Sensitivity, specificity, PPV, NPV and accuracy of CPP and LBP for detection CIN 2 or higher and cancer were comparable.

Cervical cancer incidence after normal cytological sample in routine screening using SurePath, ThinPrep, and conventional cytology: population based study

Objective To compare the cumulative incidence of cervical cancer diagnosed within 72 months after a normal screening sample between conventional cytology and liquid based cytology tests SurePath and ThinPrep.Design Retrospective population based cohort study.Setting Nationwide network and registry of histo- and cytopathology in the Netherlands (PALGA), January 2000 to March 2013.Population Women with 5 924 474 normal screening samples (23 833 123 person years).Exposure Use of SurePath or ThinPrep versus conventional cytology as screening test.Main outcome measure 72 month cumulative incidence of invasive cervical cancer after a normal screening sample for each screening test. Cox regression analyses assessed the hazard ratios, adjusted for calendar time, age, screening history, and socioeconomic status and including laboratories as random effects.Results The 72 month cumulative cancer incidence was 58.5 (95% confidence interval 54.6 to 62.7) per 100 000 normal conventional cytology samples, compared with 66.8 (56.7 to 78.7) for ThinPrep and 44.6 (37.8 to 52.6) for SurePath. Compared with conventional cytology, the hazard of invasive cancer was 19% lower (hazard ratio 0.81, 95% confidence interval 0.66 to 0.99) for SurePath, mainly caused by a 27% lower hazard (0.73, 0.57 to 0.93) of a clinically detected cancer. For ThinPrep, the hazard was on average 15% higher (hazard ratio 1.15, 0.95 to 1.38), mainly caused by a 56% higher hazard of a screen detected cancer (1.56, 1.17 to 2.08).Conclusions These findings should provoke reconsideration of the assumed similarity in sensitivity to detect progressive cervical intraepithelial neoplasia between different types of liquid based cytology and conventional cytology.

Evaluation of RNA and DNA extraction from liquid-based cytology specimens

Molecular diagnosis using DNA and RNA derived from malignant tumors and molecular biological tools such as the quantitative polymerase-chain-reaction (qPCR) is a commonly used technique in clinical pathology. In this report, we compared the qualitative extraction of RNA and DNA from cancer cells fixed using several liquid-based cytology (LBC) kits. Ten to 1,000 cells from the T24 urinary bladder cancer cell line and SKG-II cervical cancer cell line were fixed with 55% methanol and three different methanol-based LBC solutions. The mRNA levels of CD44 in T24 cells and E7 in SKG-II cells and DNA levels of p53 in T24 cells and E7 in SKG-II cells were analyzed by qPCR. mRNA and DNA extracted from T24 and/or SKG-II cells fixed with methanol-based LBC solutions were efficiently detected, but to differing degrees, by qPCR. mRNA, and DNA from cells fixed with a formaldehyde-containing fixative liquid were detected at significantly low copy numbers by qPCR. Our results demonstrate that LBC systems are powerful tools for cytopathology and immunocytochemistry applications. However, the appropriate fixative must be selected for cell preservation when a small number of LBC samples is used for molecular testing, particularly in RNA-based molecular analyses. Diagn. Cytopathol. 2016;44:833-840. © 2016 Wiley Periodicals, Inc.

Genotyping for Human Papillomavirus (HPV) 16/18/52/58 Has a Higher Performance than HPV16/18 Genotyping in Triaging Women with Positive High-risk HPV Test in Northern Thailand

Background

Testing for high-risk human papillomavirus DNA (HPV test) has gained increasing acceptance as an alternative method to cytology in cervical cancer screening. Compared to cytology, HPV test has a higher sensitivity for the detection of histologic high-grade squamous intraepithelial lesion or worse (HSIL+), but this could lead to a large colposcopy burden. Genotyping for HPV16/18 has been recommended in triaging HPV-positive women. This study was aimed to evaluate the screening performance of HPV testing and the role of genotyping triage in Northern Thailand.

Methods

A population-based cervical screening program was performed in Chiang Mai (Northern Thailand) using cytology (conventional Pap test) and HPV test (Hybrid Capture 2). Women who had abnormal cytology or were HPV-positive were referred for colposcopy. Cervical samples from these women were genotyped using the Linear Array assay.

Results

Of 5,456 women, 2.0% had abnormal Pap test results and 6.5% tested positive with Hybrid Capture 2. Of 5,433 women eligible for analysis, 355 with any positive test had histologic confirmation and 57 of these had histologic HSIL+. The sensitivity for histologic HSIL+ detection was 64.9% for Pap test and 100% for Hybrid Capture 2, but the ratio of colposcopy per detection of each HSIL+ was more than two-fold higher with Hybrid Capture 2 than Pap test (5.9 versus 2.8). Genotyping results were available in 316 samples. HPV52, HPV16, and HPV58 were the three most common genotypes among women with histologic HSIL+. Performance of genotyping triage using HPV16/18/52/58 was superior to that of HPV16/18, with a higher sensitivity (85.7% versus 28.6%) and negative predictive value (94.2% versus 83.9%).

Conclusions

In Northern Thailand, HPV testing with genotyping triage shows better screening performance than cervical cytology alone. In this region, the addition of genotyping for HPV52/58 to HPV16/18 is deemed necessary in triaging women with positive HPV test.

Performance of HPV DNA testing with hybrid capture 2 in triaging women with minor cervical cytologic abnormalities (ASC-US/LSIL) in Northern Thailand

BACKGROUND

Minor cervical cytologic abnormalities include atypical squamous cells of undetermined significance (ASC-US) and low-grade squamous intraepithelial lesion (LSIL). Approximately 10-20% of women with minor cytologic abnormalities have histologic high-grade squamous intraepithelial or worse lesions (HSIL+). In Thailand, women with minor cytologic abnormalities have a relatively high risk of cervical cancer, and referral for colposcopy has been suggested. A triage test is useful in the selection of women at risk for histologic HSIL+ to reduce the colposcopy burden. The aim of this study was to assess the performance of high-risk HPV DNA test in triage of women with minor cytologic abnormalities in northern Thailand.

MATERIALS AND METHODS

All women with ASC-US/LSIL cytology who were referred to our colposcopy clinic from October 2010 to February 2014 were included. HPV DNA testing was performed using Hybrid Capture 2 (HC2). All patients received colposcopic examination. Accuracy values of HC2 in predicting the presence of histologic HSIL+ were calculated.

RESULTS

There were 238 women in this study (121 ASC-US and 117 LSIL). The HC2 positivity rate was significantly higher in the LSIL group than in ASC-US group (74.8% versus 41.0%, p<0.001). Histologic HSIL+ was detected in 9 women (7.4%) in the ASC-US group and 16 women (13.7%) in the LSIL group (p=0.141). There was no histologic HSIL+ detected among HC2-negative cases (sensitivity and negative predictive value of 100%). The performance of HC2 triage was highest among women aged >50 years with ASC-US cytology. An increase in the cut-off threshold for positive HC2 resulted in a substantial decrease of sensitivity and negative predictive value.

CONCLUSIONS

HPV DNA testing with HC2 shows very high sensitivity and negative predictive value in triage of women with minor cervical cytologic abnormalities in northern Thailand. An increase of the cut-off threshold for HC2 triage is not recommended in this region.

Human papillomavirus type 16 viral load in relation to HIV infection, cervical neoplasia and cancer in Senegal

BACKGROUND

The importance of human papillomavirus (HPV) viral load in the pathogenesis of cervical cancer among HIV-infected and HIV-uninfected women has not yet been established.

METHODS

In this cross-sectional study, HPV-16 viral loads were measured using previously-collected and frozen cervical swab samples from 498 HPV-16 positive Senegalese women (368 HIV-seronegative, 126 HIV-1 and/or HIV-2 seropositive). The real-time polymerase chain reaction assay was used to quantify HPV-16 E7 copy number normalized by human cellular DNA (β-actin), and viral loads were log10 transformed. Associations between HPV-16 viral load, degree of cervical abnormality, and HIV status were assessed using multinomial and linear regression methods.

RESULTS

Compared to women with normal cytology, the likelihood of CIN1 (ORa: 1.21, 95% CI 0.93-1.57), CIN2-3 (ORa: 2.38, 95% CI 1.72-3.29) and cancer (ORa: 2.12, 95% CI 1.52-2.96) was found to increase for each 1-unit log10 increase in HPV-16 viral load. Compared to HIV-negative women, HIV-positive women had higher average HPV-16 viral load values (βa: 0.39, 95% CI 0.03-0.75), even after accounting for degree of cervical abnormality.

CONCLUSION

In our study of women including those with cancer, HPV-16 viral load was associated with a higher likelihood of cervical abnormalities. However, substantial overlaps across categories of disease severity existed. Higher viral load among HIV-infected individuals may indicate that HIV infection influences HPV viral replication factors.