Comparison of CINtec PLUS cytology and cobas HPV test for triaging Canadian patients with LSIL cytology referred to colposcopy: A two-year prospective study

A Predictive Model Using Six Genes DNA Methylation Markers to Identify Individuals With High Risks of High-Grade Squamous Intraepithelial Lesions and Cervical Cancer

Background

Cervical cancer is preceded by low-grade squamous intraepithelial lesions (LSIL) and high-grade squamous intraepithelial lesions (HSIL). Human papillomavirus (HPV) test is a sensitive method for cervical cancer screening, but it is less specific compared with cytological examination, leading to overtreatment and reduced patient compliance. Therefore, new detection methods that can improve the accuracy of cervical cancer screening are needed.

Methods

In the present study, cervical exfoliated cell samples were collected from 228 Chinese individuals, including 114 healthy control individuals, 46 patients with LSIL, 21 patients with HSIL and 47 patients with cervical cancer. The DNA methylation levels of 12 cervical cancer-related genes were detected using quantitative multiplex methylation-specific PCR. All individuals were divided into high- or low-risk groups. Patients with HSIL and cervical cancer were assigned to the high-risk group, whereas healthy controls and patients with LSIL were assigned to the low-risk group. The ability to predict cancer risks was evaluated using ROC curves and a predictive model for cancer risk was constructed by linear regression analysis.

Results

The methylation levels were significantly higher for all 12 genes in individuals with cervical cancer or HSIL, compared with those in LSIL or normal group. Family with sequence similarity 19 member A4 (FAM19A4), phosphatase and actin regulator 3 (PHACTR3), somatostatin (SST), Zic family member 1 (ZIC1), paired box 1 (PAX1) and zinc finger protein 671 (ZNF671) were used to construct a predictive model for cancer risk prediction, with a specificity of 89.6% and a sensitivity of 95.0%.

Conclusion

The present study demonstrated the methylation levels of 12 cervical cancer-related genes were higher in Chinese patients with HSIL or cervical cancer. Also, a predictive model was constructed to distinguish cervical cancer or HSCL from individuals with low risk.

Evaluation of dual p16/Ki-67 immunostaining on anal cytology specimens

INTRODUCTION

Dual immunostaining for p16/Ki67 is FDA-approved for use on liquid-based cervical cytology specimens; however, the utility of dual staining in anal cytology especially for ASCUS risk stratification is not well established.

METHODS

We investigated dual staining performance on anal cytology specimens and correlated with subsequent cytologic interpretation, high-risk HPV status, and anal biopsy results. Dual staining for p16/Ki-67 was performed on all liquid-based anal cytology specimens from December 2021 to June 2022 (n = 43).

RESULTS

Three patients had high grade squamous intraepithelial lesion (HSIL/AIN2-3) on biopsy; dual staining was positive in all three cases. All HR-HPV negative cases were negative for dual staining. Among the 12 ASCUS samples with subsequent anal biopsy results all also had HR-HPV testing. Due to small sample size of cases with squamous intraepithelial lesion (SIL) diagnosed on biopsy, the sensitivity and positive predictive value was not calculated. However, the specificity and negative predictive value of p16/Ki-67 dual staining for SIL of any grade on biopsy were 1 (95% CI: 0.66-1) and 0.9 (95% CI: 0.65-0.97) respectively, whereas the specificity and negative predictive value of HR-HPV testing for SIL of any grade on biopsy were 0.44 (95% CI: 0.14-0.79) and 0.8 (95% CI: 0.41-0.96) respectively.

CONCLUSION

Dual p16/Ki-67 staining indicates transforming HPV infection and could help serve as an ancillary test for risk stratification for atypical anal cytology specimens. Among ASCUS samples, dual staining was specific for SIL of any grade with a high negative predictive value and therefore could be useful in clinical practices with limited availability for follow-up care.

Enhancing Cervical Cancer Screening: Review of p16/Ki-67 Dual Staining as a Promising Triage Strategy

Cervical cancer, primarily caused by high-risk human papillomavirus (HR-HPV) types 16 and 18, is a major global health concern. Persistent HR-HPV infection can progress from reversible precancerous lesions to invasive cervical cancer, which is driven by the oncogenic activity of human papillomavirus (HPV) genes, particularly E6 and E7. Traditional screening methods, including cytology and HPV testing, have limited sensitivity and specificity. This review explores the application of p16/Ki-67 dual-staining cytology for cervical cancer screening. This advanced immunocytochemical method allows for simultaneously detecting p16 and Ki-67 proteins within cervical epithelial cells, offering a more specific approach for triaging HPV-positive women. Dual staining and traditional methods are compared, demonstrating their high sensitivity and negative predictive value but low specificity. The increased sensitivity of dual staining results in higher detection rates of CIN2+ lesions, which is crucial for preventing cervical cancer progression. However, its low specificity may lead to increased false-positive results and unnecessary biopsies. The implications of integrating dual staining into contemporary screening strategies, particularly considering the evolving landscape of HPV vaccination and changes in HPV genotype prevalence, are also discussed. New guidelines and further research are necessary to elucidate the long-term effects of integrating dual staining into screening protocols.

Validation of an on-chip p16ink4a/Ki-67 dual immunostaining cervical cytology system using microfluidic device technology

More specific screening systems for cervical cancer may become necessary as the human papillomavirus (HPV) vaccine becomes more widespread. Although p16/Ki-67 dual-staining cytology has several advantages, it requires advanced diagnostic skills. Here, we developed an automated on-chip immunostaining method using a microfluidic device. An electroactive microwell array (EMA) microfluidic device with patterned thin-film electrodes at the bottom of each microwell was used for single-cell capture by dielectrophoresis. Immunostaining and dual staining for p16/Ki-67 were performed on diagnosed liquid cytology samples using the EMA device. The numbers of p16/Ki-67 dual-stained cells captured by the EMA device were determined and compared among the cervical intraepithelial neoplasia (CIN) lesion samples. Seven normal, fifteen CIN grade 3, and seven CIN grade 2 samples were examined. The percentage of dual-positive cells was 18.6% in the CIN grade 2 samples and 23.6% in the CIN grade 3 samples. The percentages of dual-positive staining increased significantly as the severity of the cervical lesions increased. p16/Ki67 dual immunostaining using the EMA device is as sensitive as the conventional method of confirming the histopathological diagnosis of cervical samples. This system enables a quantified parallel analysis at the individual cell level.