Establishment of a Korea HPV cohort study

Application of Machine Learning Algorithms for Risk Stratification and Efficacy Evaluation in Cervical Cancer Screening among the ASCUS/LSIL Population: Evidence from the Korean HPV Cohort Study

PURPOSE

We assessed human papillomavirus (HPV) genotype-based risk stratification and the efficacy of cytology testing for cervical cancer screening in patients with atypical squamous cells of undetermined significance (ASCUS)/low-grade squamous intraepithelial lesion (LSIL).

MATERIALS AND METHODS

Between 2010 and 2021, we monitored 1,273 HPV-positive women with ASCUS/LSIL every 6 months for up to 60 months. HPV infections were categorized as persistent (HPV positivity consistently observed post-enrollment), negative (HPV negativity consistently observed post-enrollment), or non-persistent (neither consistently positive nor negative). HPV genotypes were grouped into high-risk (Hr) groups 1 (types 16, 18, 31, 33, 45, 52, and 58) and 2 (types 35, 39, 51, 56, 59, 66, and 68) and a low-risk group. Hr1 was subdivided into types (a) 16 and 18; (b) 31, 33, and 45; and (c) 52 and 58. Cox regression and machine learning (ML) algorithms were used to analyze progression rates.

RESULTS

Among 1,273 participants, 17.6% with persistent HPV infections experienced disease progression versus no progression in the HPV-negative group (p < 0.001). Cox analysis revealed the highest hazard ratios (HRs) for Hr1-a (11.6, p < 0.001), followed by Hr1-b (9.26, p < 0.001) and Hr1-c (7.21, p < 0.001). HRs peaked at 12-24 months, with Hr1-a maintaining significance at 24-36 months (10.7, p=0.034). ML analysis identified the final cytology change pattern as the most significant factor, with 14-15 months the optimal time for detecting progression from the first examination.

CONCLUSION

In ASCUS/LSIL cases, follow-up strategies should be based on HPV risk types. Annual follow-up was the most effective monitoring for detecting progression/regression.

HPV vaccination status and effectiveness in Korean women with HPV16/18 infection (2010-2021): a retrospective study

OBJECTIVE

To evaluate human papillomavirus (HPV) vaccine effectiveness in a cohort of Korean women infected with HPV.

METHODS

From 2010 to 2021, Korean women aged 20-60 years who diagnosed HPV-positive atypical squamous cells of undetermined significance or low-grade squamous intraepithelial lesion were recruited from 6 hospitals. HPV vaccine effectiveness was estimated by observing the differences in pathological and clinical information and experimental results-prevalence, viral load (VL), physical state (PS), and HPV16/18 infection duration-between the vaccinated and unvaccinated groups.

RESULTS

HPV16/18 prevalence declined from 18.5% to 11.8% as vaccination rates increased from 14.3% to 60.7% in the 1,757 registered cohort women. DNA analysis from 96 samples collected from the participants, indicated that HPV vaccination reduced HPV16 VL by 6 times and increased E2/E6 ratio for both HPV16 and HPV18 by 1.4 and 5 times, respectively. The HPV16 infection rate-lasting more than 18 months from 31.0% to 21.6%-and the HPV18 infection rate-lasting more than 12 and less than 24 months from 35.5% to 21.1%-were reduced by vaccination. We found VL and the infection duration to be directly proportional. Moreover, HPV vaccination reduced not only the VL to 1/4 in both the persistence and clearance groups but also the persistence rate from 90% (27/30) to 70.6% (12/17) in HPV16.

CONCLUSION

HPV vaccination reduced the prevalence and duration of infection and kept the PS in an episomal form for both HPV16 and HPV18. The tendency of persistence VL to be higher than clearance in the unvaccinated group implies that the vaccine's effect of reducing VL in HPV16 may lower the risk of progression to cervical cancer by shortening the infection duration.

Menopausal status induces vaginal dysbiosis in women with human papillomavirus infection

In this study, we examined the difference in the vaginal microbiota of women infected with human papillomavirus (HPV), according to menopausal status. A total of 75 cervicovaginal swab samples from 38 pre- and 37 postmenopausal women with HPV infection were obtained from the Korean HPV cohort. Vaginal microbiota analysis, including microbial diversity and specific bacterial abundances, was performed using 16S rRNA gene sequencing. The mean age of the pre- and postmenopausal women were 29.5 and 55.8 years, respectively (p < 0.0001). Lactobacillus spp. were predominant in both groups; however, a marked decrease was observed in postmenopausal women compared to premenopausal women (44.3% vs. 74.2%). Various anaerobic bacteria also showed a relatively high abundance in the postmenopausal group; Atopobium vagina and Gardnerella vaginalis significantly increased in postmenopausal women. Interestingly, no significant differences in bacterial richness were observed between the two groups. However, significant differences in beta-diversity were observed using the Bray-Curtis (p = 0.001), Generalized UniFrac (p = 0.002), Jensen-Shannon (p = 0.001), and UniFrac algorithms (p = 0.002). Theres results indicate that postmenopausal women with HPV infection exhibited a higher degree of vaginal dysbiosis than premenopausal women. Further, HPV-infected postmenopausal women had increased vaginal microbial diversity, characterized by an increase in anaerobic bacteria and concomitant depletion of Lactobacillus spp.

MGMT Methylation Is Associated with Human Papillomavirus Infection in Cervical Dysplasia: A Longitudinal Study

Cervical premalignancy/malignancy, as detected by cervical cytology or biopsy, can develop as a result of human papillomavirus (HPV) infection. Meanwhile, DNA methylation is known to be associated with carcinogenesis. In this study, we thus attempted to identify the association between MGMT methylation and persistent HPV infection using an Epi-TOP MPP assay. Integrative analysis of DNA methylation was carried out here using longitudinal cervical cytology samples of seven patients with atypical squamous cells of undetermined significance/low-grade squamous intraepithelial lesion (ASC-US/LSIL). Then, a gene expression analysis using the longitudinal cervical cytology samples and a public database (The Cancer Genome Atlas (TCGA)) was performed. Upon comparing the ASC-US or LSIL samples at the 1st collection and the paired samples at the 2nd collection more than 6 months later, we found that they became hypermethylated over time. Then, using the longitudinal data, we found that the MGMT methylation was associated with HPV infection. Moreover, TCGA dataset revealed an association between downregulated MGMT mRNA expression and poor overall survival. This decreased MGMT mRNA expression was observed to have an inverse relationship with MGMT methylation levels. In this study, we found that the MGMT methylation level could potentially serve as a valuable prognostic indicator for the transition from ASC-US/LSIL to cervical cancer.

Prognostic Relevance of BRCA1 Expression in Survival of Patients With Cervical Cancer

Objective

BRCA1 expression can be lost by a variety of mechanisms including germline or somatic mutation and promotor hypermethylation. Given the potential importance of BRCA1 loss as a predictive and prognostic biomarker in several cancers, the objective of this study was to investigate BRCA1 expression using immunohistochemistry (IHC) in cervical cancer and its possible prognostic relevance.

Methods

Seventy patients with cervical cancer were enrolled in this study. Samples from each tumor were stained for BRCA1 and reviewed independently by gynecologic pathologists blinded to the BRCA status. Kaplan-Meier methods were used to estimate overall survival according to BRCA1 expression. Differentially expressed genes (DEGs) by BRCA1 expression were selected using GSE44001 dataset, which included 300 samples treated with radical hysterectomy. In addition, cox regression analysis with backward elimination was performed to select independent prognostic markers. Gene set enrichment analysis (GSEA) was done using these DEGs.

Results

BRCA1 IHC was positive in 62.9% (44/70) of cases. Patients with BRCA1 expression showed better overall survival (100% vs. 76.2%, HR 0.20, 95% CI 0.04 - 0.99, p = 0.028) than those without BRCA1 expression. Analysis of gene expression profiles according to BRCA1 expression identified 321 differentially expressed mRNAs. Gene set enrichment analysis results showed two dysregulated pathways (VEGF_A_UP.V1_DN and E2F1_UP.V1_UP). Of these DEGs, alterations of 20 gene signatures were found to be independently associated with survival outcomes of patients.

Conclusions

BRCA1 expression in cervical cancer tissue is associated with survival. In addition, the identification of specific gene alterations associated with BRCA1 expression could help to provide individualized prediction in these patients.

Enhanced disease progression due to persistent HPV-16/58 infections in Korean women: a systematic review and the Korea HPV cohort study

BACKGROUND

Persistent human papillomavirus (HPV) infection is a key factor for the development and progression of cervical cancer. We sought to identify the type-specific HPV prevalence by cervical cytology and assess disease progression risk based on high-risk persistent HPV infection in South Korea.

METHODS

To investigate the HPV prevalence by Pap results, we searched seven literature databases without any language or date restrictions until July 17, 2019. To estimate the risk of disease progression by HPV type, we used the Korea HPV Cohort study data. The search included the terms "HPV" and "Genotype" and "Korea." Studies on Korean women, type-specific HPV distribution by cytological findings, and detailed methodological description of the detection assay were included. We assessed the risk of disease progression according to the high-risk HPV type related to the nonavalent vaccine and associated persistent infections in 686 HPV-positive women with atypical squamous cells of uncertain significance or low-grade squamous intraepithelial lesions from the Korea HPV Cohort Study. Type-specific HPV prevalence was the proportion of women positive for a specific HPV genotype among all HPV-positive women tested for that genotype in the systematic review.

RESULTS

We included 23 studies in our review. HPV-16 was the most prevalent, followed by HPV-58, -53, -70, -18, and -68. In women with high-grade squamous intraepithelial lesions, including cancer, HPV-16, -18, and -58 were the most prevalent. In the longitudinal cohort study, the adjusted hazard ratio of disease progression from atypical squamous cells of uncertain significance to high-grade squamous intraepithelial lesions was significantly higher among those with persistent HPV-58 (increase in risk: 3.54-5.84) and HPV-16 (2.64-5.04) infections.

CONCLUSIONS

While HPV-16 was the most prevalent, persistent infections of HPV-16/58 increased the risk of disease progression to high-grade squamous intraepithelial lesions. Therefore, persistent infections of HPV-16 and -58 are critical risk factors for cervical disease progression in Korea. Our results suggest that equal attention should be paid to HPV-58 and -16 infections and provide important evidence to assist in planning the National Immunization Program in Korea.

Risk of cervical dysplasia among human papillomavirus-infected women in Korea: a multicenter prospective study

Objective

Human papillomavirus (HPV) infection is the most important risk factor for cervical cancer, which progresses from precursor lesions with no symptom if left untreated. We compared the risk of cervical dysplasia among HPV-positive Korean women based on HPV types and infection patterns.

Methods

We observed participants of a 5-year multicenter prospective cohort study, comprising HPV-positive women with either atypical squamous cells of undetermined significance or low-grade squamous intraepithelial lesion of the cervix at their enrollment. Follow-ups, comprising cytology and HPV DNA testing results, were included in the final analysis. Incidence was calculated for each infection pattern (persistent infection, incidental infection, and clearance). To investigate cervical dysplasia risk, we used Cox proportional hazard models adjusted for variables that were significantly different among infection patterns. From April 2010 to September 2017, 71 of 1,027 subjects developed cervical dysplasia more severe than high-grade squamous intraepithelial lesion of the cervix.

Results

Of these 71 subjects, persistent infection, incidental infection, and clearance were noted in 30, 39, and 2 individuals, respectively. Based on changes in DNA results during follow-up, cumulative incidence was 27.2%, 10.4%, and 0.5% for persistent infection, incidental infection, and clearance, respectively. Compared to clearance, the adjusted hazard ratios for cervical dysplasia were 51.6 and 24.1 for persistent and incidental infections, respectively (p<0.001).

Conclusion

Individuals persistently infected with the same HPV types during the follow-up period had the highest risk of severe cervical dysplasia. Hence, it is necessary to monitor HPV types and infection patterns to prevent severe cervical precancerous lesions.

Retrospective analysis of cervical cancer and precancerous lesions in patients with atypical squamous cells of undetermined significance in China

Atypical squamous cells of undetermined significance (ASCUS) are the most common cytological abnormality of all smear test. No study has demonstrated the prevalence of cervical cancer or its precursor in Chinese patients with ASCUS. This study aims to investigate the prevalence of cervical intraepithelial neoplasia 1 or worse (CIN1+) and CIN3 or worse (CIN3+) in patients with ASCUS in China to provide insight into appropriate management for Chinese health care.In a retrospective cross-sectional study, patients who underwent liquid-based thin layer cytology and human papillomavirus (HPV) co-testing at the Peking Union Medical College Hospital between January 2014 and January 2017, and had ASCUS results on liquid-based thin layer cytology test and underwent follow-up and colposcopic biopsy were included. Age, HPV DNA test, and pathological outcomes were assessed.One hundred forty-four patients with ASCUS and positive HPV test results were included. In the 3-year follow-up, 23 (16.0%) patients had CIN1, 28 (19.4%) had CIN2, and 17 (11.8%) had CIN3 or carcinoma in situ. The risk of CIN3+ was significantly higher in those older than 60 years (42.8%, P = .005), whereas the CIN1+ prevalence displayed no significant difference between age groups. Both hybrid Capture II (HC II) value and cytopathological description of HPV infection showed no statistically significant correlation with CIN1+ or CIN3+.Patients with HPV-positive ASCUS who were older than 60 years had a significantly higher risk of CIN3+, and clinicians should pay more attention to them. Both HC II value and cytopathological description of HPV infection showed no significant correlation with CIN1+ or CIN3+.

Prognostic Model for Survival and Recurrence in Patients with Early-Stage Cervical Cancer: A Korean Gynecologic Oncology Group Study (KGOG 1028)

PURPOSE

We aimed to develop and validate individual prognostic models in a large cohort of cervical cancer patients that were primarily treated with radical hysterectomy.

Materials and Methods

We analyzed 1,441 patients with early-stage cervical cancer treated between 2000 and 2008 from the Korean Gynecologic Oncology Group multi-institutional cohort: a train cohort (n=788) and a test cohort (n=653). Models predicting the risk for overall survival (OS), disease- free survival (DFS), lymphatic recurrence and hematogenous recurrence were developed using Cox analysis and stepwise backward selection and best-model options. The prognostic performance of each model was assessed in an independent patient cohort. Model-classified risk groups were compared to groups based on traditional risk factors.

RESULTS

Independent risk factors for OS, DFS, lymphatic recurrence, and hematogenous recurrence were identified for prediction model development. Different combinations of risk factors were shown for each outcome with best predictive value. In train cohort, area under the curve (AUC) at 2 and 5 years were 0.842/0.836 for recurrence, and 0.939/0.882 for OS. When applied to a test cohort, the model also showed accurate prediction result (AUC at 2 and 5 years were 0.799/0.723 for recurrence, and 0.844/0.806 for OS, respectively). The Kaplan-Meier plot by proposed model-classified risk groups showed more distinctive survival differences between each risk group.

CONCLUSION

We developed prognostic models for OS, DFS, lymphatic and hematogenous recurrence in patients with early-stage cervical cancer. Combining weighted clinicopathologic factors, the proposed model can give more individualized predictions in clinical practice.

Comparison of laparoscopic and abdominal radical hysterectomy in early stage cervical cancer patients without adjuvant treatment: Ancillary analysis of a Korean Gynecologic Oncology Group Study (KGOG 1028)

OBJECTIVE

We compared two groups of early stage cervical cancer patients treated with different surgical methods without adjuvant treatment using retrospective multicenter data previously collected for Korean Gynecologic Oncology Group (KGOG) study designed for developing prognostic models.

METHOD

We initially assessed data from the multi-institutional cohort with early stage (IB-IIA) cervical cancer patients treated with radical hysterectomy without adjuvant treatment between 2000 and 2008. Propensity score matching was performed to compare disease-free survival (DFS) and overall survival (OS) of patients with laparoscopic to abdominal radical hysterectomy. Additionally, survival comparison was performed in patients with tumor size <2 cm.

RESULTS

After matching, 119 patients with laparoscopic radical hysterectomy were compared with 357 patients with abdominal radical hysterectomy (median follow-up of 63.9 months). Inferior DFS was observed in the laparoscopy group (HR 2.738 [95% CI 1.326-5.650], p = 0.005) with a significant difference in pelvic (HR 5.110 [95% CI 1.817-14.473], p < 0.001) and hematogenous recurrence (HR 3.171 [95% CI 1.059-9.494], p = 0.03), but OS was not significantly different between two groups (p = 0.624). In subgroup analysis in the patient with tumor size <2 cm (laparoscopy 62 vs. laparotomy 186, median follow-up of 69.1 months), laparoscopy was associated with lower rate of DFS (HR 12.987 [95% CI 1.451-116.244], p = 0.003), but no significant difference in OS was observed between groups. Regarding OS, number of events is lacking, and inferior DFS in the laparoscopy group may be compensated by better response to radiation therapy in pelvic recurrence.

CONCLUSIONS

In this analysis, laparoscopic radical hysterectomy was associated with lower rates of DFS but not OS in early stage cervical cancer patients without adjuvant treatment. Further larger scale studies are needed.

Status of HPV vaccination among HPV-infected women aged 20-60 years with abnormal cervical cytology in South Korea: a multicenter, retrospective study

OBJECTIVES

Since 2007, human papillomavirus (HPV) vaccines have been administered for the prevention of cervical cancer in Korea. We investigated the status of HPV vaccination among HPV-infected adult women with abnormal cervical cytology before the introduction of National Immunization Program.

METHODS

From 2010 to 2016, HPV-positive women (age, 20-60 years) with atypical squamous cells of undetermined significance or low-grade squamous intraepithelial lesion (LSIL) were enrolled from five hospitals across Korea. Their HPV genotype, epidemiologic, and clinical data, including HPV vaccination history, were obtained. We compared the epidemiological characteristics and prevalence of HPV-16/18 genotypes between vaccinated and unvaccinated women.

RESULTS

Among the 1,300 women, approximately 26% had a history of vaccination. Vaccinated patients were significantly younger, unmarried, and had a higher education level than unvaccinated women. For HPV-vaccinated individuals by vaccine dose, there was a significant younger age at vaccination initiation (p=0.025), longer duration from HPV vaccination to Pap test date (p=0.001), and lower proportion of HPV-16/18 (p=0.028) in the women with three doses. There was a significantly lower prevalence of HPV-16/18 genotypes in women who were vaccinated at least 12 months prior than in unvaccinated women (adjusted prevalence ratio [aPR]=0.51; 95% confidence interval [CI]=0.29-0.88). For women with LSIL, the prevalence of the HPV-16/18 genotypes was significantly lower in women who were vaccinated more than 12 months prior than in unvaccinated women (aPR=0.35; 95% CI=0.13-0.96).

CONCLUSION

This study highlighted the status of HPV vaccination and the prevalence of HPV-16/18 genotypes among HPV-infected women with abnormal cervical cytology according to HPV vaccination. It provides preliminary information regarding the status of HPV vaccination among Korean adult women.

Risk factors for cytological progression in HPV 16 infected women with ASC-US or LSIL: The Korean HPV cohort

Objective

This study was to identify the risk factors for cytological progression in women with atypical squamous cells of undetermined significance (ASC-US) or low-grade squamous intraepithelial lesions (LSIL).

Methods

We analyzed data from women infected with the human papillomavirus (HPV) who participated in the Korean HPV cohort study. The cohort recruited women aged 20-60 years with abnormal cervical cytology (ASC-US or LSIL) from April 2010. All women were followed-up at every 6-month intervals with cervical cytology and HPV DNA testing.

Results

Of the 1,158 women included, 654 (56.5%) and 504 (43.5%) women showed ASC-US and LSIL, respectively. At the time of enrollment, 143 women tested positive for HPV 16 (85 single and 58 multiple infections). Cervical cytology performed in the HPV 16-positive women showed progression in 27%, no change in 23%, and regression in 50% of the women at the six-month follow-up. The progression rate associated with HPV 16 infection was higher than that with infection caused by other HPV types (relative risk [RR], 1.75; 95% confidence interval [CI], 1.08-2.84; P=0.028). The cytological progression rate in women with persistent HPV 16 infection was higher than that in women with incidental or cleared infections (P<0.001). Logistic regression analysis showed a significant relationship between cigarette smoking and cytological progression (RR, 4.15; 95% CI, 1.01-17.00).

Conclusion

The cytological progression rate in HPV 16-positive women with ASC-US or LSIL is higher than that in women infected with other HPV types. Additionally, cigarette smoking may play a role in cytological progression.

DNA methylation in human papillomavirus-infected cervical cells is elevated in high-grade squamous intraepithelial lesions and cancer

Objective

DNA methylation has been shown to be a potential biomarker for early cancer detection. The aim of this study was to evaluate DNA methylation profiles according to liquid-based Pap (LBP) test results and to assess their diagnostic value in a Korean population.

Methods

A total of 205 patients with various Papanicolaou test results were enrolled to this study (negative, 26; atypical squamous cells of undetermined significance, 39; low grade squamous intraepithelial lesion, 44; high grade squamous intraepithelial lesion (HSIL), 48; and cancer, 48). DNA methylation analysis of four genes, ADCYAP1, PAX1, MAL, and CADM1, was performed on residual cervical cells from LBP samples using a quantitative bisulfite pyrosequencing method. To evaluate the diagnostic performance of the four methylated genes for cancer detection, receiver operating characteristic (ROC) curves were drawn. Sensitivities and specificities were also tested at cutoffs determined from the ROC curves.

Results

Cervical cancer cells showed dramatically increased methylation levels for the four genes analyzed. ADCYAP1 and PAX1 also trended toward elevated methylation levels in HSIL samples, although the levels were much lower than those in cancer cells. The sensitivities of methylated ADCYAP1, PAX1, MAL, and CADM1 for the detection of cancer were 79.2%, 75.0%, 70.8%, and 52.1%, and the specificities were 92.0%, 94.0%, 94.7%, and 94.0%, respectively. Methylated ADCYAP1 and PAX1 demonstrated relatively better discriminatory ability than did methylated MAL and CADM1 (area under the curves 0.911 and 0.916 vs. 0.854 and 0.756, respectively).

Conclusion

DNA methylation status, especially in the ADCYAP1 and PAX1 genes, showed relatively good specificity, ranging from 90% to 94%. The possible additive and complementary roles of DNA methylation testing with respect to conventional cervical cancer screening programs will need to be validated in prospective population-based studies.

Application of multiplex PCR for Rapid and sensitive detection of human papillomaviruses in cervical cancer

Objectives:

Reffering to an increase in cervical cancer in the recent years, rapid, sensitive and economical detection of human papillomaviruses (HPVs) as causative agents of cervical cancer is important. The traditional methods for the detection of HPVs in cervical cancer, such as pap smear, suffer from limitation and PCR has a potential to overcome the limitaitons. The purpose of present research work was to identify the five important strains of HPV (16, 18, 31, 33 and 45) simultaneously by Multiplex PCR application.

Methods:

Study was done on 100 cervical lesions of women. DNA was extracted from specimens by a genomic DNA purification kit. A 5-plex PCR was developed for the simultaneous detection of major HPV. Five pair of new primers was designed for detection of HPV 16, 18, 31, 33 and 45 by Multiplex PCR.

Results:

Among the 100 evaluated samples, 82 were found positive to HPVs. In the meantime the highest rate of infection was for HPV 16. Also 30 of HPV positive samples had infections with two or more HPV types.

Conclusion:

Multiplex PCR assay used in present study can provide a rapid, sensitive and economical method for detection of viral infections and is applicable to small volumes of vaginal samples.

The Impact of High-Risk HPV Genotypes Other Than HPV 16/18 on the Natural Course of Abnormal Cervical Cytology: A Korean HPV Cohort Study

Purpose

The purpose of this study is to evaluate the impact of high-risk human papillomaviruses (HPVs) other than HPV 16/18 on the natural course of atypical squamous cells of undetermined significance (ASC-US) or low-grade squamous intraepithelial lesion (LSIL).

Materials and Methods

The study population was derived from the Korean HPV cohort (2010-2014). Women aged 20 to 60 who satisfied the criteria of having both HPV infection and abnormal cervical cytology of either ASC-US or LSIL were recruited from five institutions nationwide. Enrolled patients underwent cervical cytology and HPV DNA testing every 6 months.

Results

A total of 1,158 patients were enrolled. The 10 most common HPV types were HPV 16 (12.3%), 58 (10.0%), 56 (8.8%), 53 (8.4%), 52 (7.7%), 39 (6.2%), 18 (6.0%), 51 (5.7%), 68 (5.1%), and 66 (4.6%). Among these patients, 636 women were positive for high-risk HPVs other than HPV 16 or 18, and 429 women were followed for more than 6 months. Cytology evaluations showed progression in 15.3% of women, no change in 22.6%, and regression in 62.1% of women at 12 months. In cases of HPV 58 single infection, a more highly significant progression rate, compared to other high-risk types, was observed at 6 months (relative risk [RR], 3.3; 95% confidence interval [CI], 2.04 to 5.30; p < 0.001) and 12 months (RR, 5.03; 95% CI, 2.56 to 9.91; p < 0.001).

Conclusion

HPV genotypes numbered in the 50s were frequent in Korean women with ASC-US and LSIL. HPV 58 was the second most common type, with a high progression rate of cervical cytology.

MICA/B and ULBP1 NKG2D ligands are independent predictors of good prognosis in cervical cancer

BACKGROUND

NKG2D (natural killer group 2, member D) is thought to play an important role in mediating the activation of anticancer immune response. Expression of NKG2D ligands (NKG2DLs) is pronounced in malignancies and the heterogeneity of NKG2DL expression remains unclear. Here, we investigate the expression and clinical significance of NKG2DLs in cervical cancer.

METHODS

Immunohistochemical analyses of MICA/B, ULBP1, ULBP2, ULBP3, RAET1E, and RAET1G were performed using tissue microarray analysis of 200 cervical cancers, 327 high-grade cervical intraepithelial neoplasias (CINs), 99 low-grade CINs, and 541 matched nonadjacent normal cervical epithelial tissues and compared the data with clinicopathologic variables, including the survival of cervical cancer patients.

RESULTS

MICA/B, ULBP1, and RAET1E expression was higher in cervical cancer than in low-grade CIN (p<0.001, p=0.012, p=0.013, respectively) and normal cervix (all p<0.001). Among these markers, expression of ULBP1 was significantly different depending on patient tumor stage (p=0.010) and tumor size (p=0.045). ULBP1 expression was correlated with MICA/B (p<0.001) and ULBP2 (p=0.002) expression in cervical cancer. While MICA/B+ or ULBP1+ patients had improved disease-free survival time (p=0.027 and p=0.009, respectively) relative to that of the low expression group, RAET1E+ or RAET1G+ was correlated with shorter survival time (p=0.018 and p=0.029, respectively). However, in terms of overall survival, the ULBP1+ group had significantly longer survival time than the low expression group (p=0.009). Multivariate analysis indicated that MICA/B+/ULBP1+ (HR=0.16, p=0.015) and ULBP1+ (HR=0.31, p=0.024) are independent prognostic factors of disease-free survival in cervical cancer.

CONCLUSIONS

High expression of either ULBP1 or MICA/B and ULBP1 combined is an indicator of good prognosis in cervical cancer, suggesting their potential utility as prognostic tests in clinical assessment.

Human papillomavirus among women with atypical squamous cells of undetermined significance in southern Brazil

OBJECTIVE

To determine the prevalence of atypical squamous cells of undetermined significance (ASCUS) and human papillomavirus (HPV) genotypes in a population in southern Brazil.

METHODS

In a retrospective cross-sectional study, the prevalence of ASCUS was determined among women aged 20-60 years who were referred to a private medical center in Caxias do Sul by a gynecologist for assessment of a cervical condition between January 1, 2010, and September 30, 2011. Histologic and cytologic samples were tested for HPV, and polymerase chain reaction (PCR) was used to genotype any HPV DNA identified.

RESULTS

Among the 250 included women, 25 (10.0%) had ASCUS. HPV DNA was found in 15 (60.0%) women with ASCUS and 115 (51.1%) of the 225 without ASCUS. Viral typing showed that 7 (46.7%) HPV-positive women with ASCUS had multiple infections with up to five different genotypes. Both low- and high-risk HPV genotypes were found in ASCUS samples; the most prevalent genotypes were HPV6/HPV11 (affecting 10 [66.7%] women), HPV51 (6 [40.0%]), and HPV16 (6 [40.0%]).

CONCLUSION

ASCUS is not an indication of HPV infection. HPV screening and genotyping would benefit women with ASCUS, because treatment can be planned according to risk of carcinogenesis.

Development of reference materials to detect 15 different human papillomavirus genotypes

Accurate human papillomavirus (HPV) typing is essential for evaluating and monitoring HPV vaccines in cervical cancer screening and in epidemiological surveys. In our country, different HPV DNA detection and genotyping methodologies have been established for diagnosing and monitoring HPV-related disease in clinical practice and for research. However, there is a lack of reference materials to standardize the methods for HPV detection and genotyping. In this study, we constructed candidate reference materials comprising 15 targets (13 types of high-risk HPV, two types of low-risk HPV). We evaluated whether the candidate reference materials could be used as the reference for HPV detection and genotyping using quantitative real-time polymerase chain reaction. Standard curves for the wide linear range (10(1)-10(6)copies/μL) produced high correlation regression coefficient R(2) of 0.99. The reaction efficiencies were 96.3% to 101.2% for the standard curves, indicating highly efficient reactions. Specific genotypes were detected in single or multiple mixed samples. Our results suggest that these reference materials may provide useful standards for standardizing quality assurance for different HPV-typing assays and for proficiency testing in diagnostic laboratories.

Preoperative nomogram for the identification of lymph node metastasis in early cervical cancer

Background:

The objective of this study is to construct a preoperative nomogram predicting lymph node metastasis (LNM) in early-cervical cancer patients.

Methods:

Between 2009 and 2012, 493 early-cervical cancer patients received hysterectomy and pelvic/para-aortic lymphadenectomy. Patients who were diagnosed during 2009–2010 were assigned to a model-development cohort (n=304) and the others were assigned to a validation cohort (n=189). A multivariate logistic model was created from preoperative clinicopathologic data, from which a nomogram was developed and validated. A predicted probability of LNM<5% was defined as low risk.

Results:

Age, tumour size assessed by magnetic resonance imaging, and LNM assessed by positron emission tomography/computed tomography were independent predictors of nodal metastasis. The nomogram incorporating these three predictors demonstrated good discrimination and calibration (concordance index=0.878; 95% confidence interval (CI), 0.833−0.917). In the validation cohort, the discrimination accuracy was 0.825 (95% CI, 0.736−0.895). In the model-development cohort, 34% of them were classified as low risk and negative predictive value (NPV) was 99.0%. In the validation cohort, 38% were identified as low risk and NPV was 95.8%. Integrating the model-development and validation cohorts, negative likelihood ratio was 0.094 (95% CI, 0.036−0.248).

Conclusion:

A robust nomogram predicting LNM in early cervical cancer was developed. This model may improve clinical trial design and help physicians to decide whether lymphadenectomy should be performed.