The use of biomarkers and HPV genotyping to improve diagnostic accuracy in women with a transformation zone type 3

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.

Transformation zone types: a call for review of the IFCPC terminology to embrace practice in low-resource settings

Most cervical cancers develop in the transformation zone (TZ). Type 3 TZs, where the full circumference of the squamocolumnar junction (SCJ) is not visible pose problems during cervical screening with visual inspection methods, as (pre)cancerous lesions may be missed. Several practical strategies can be implemented to convert type 3 TZs into TZ 1 or TZ 2, including the use of an endocervical speculum or hygroscopic cervical dilators, opening the vaginal speculum more widely, skillful use of cotton-tipped applicators, performing colposcopy in midcycle, and use of oral or vaginal misoprostol and estrogen to 'ripen' the cervix. With the 2011 International Federation for Cervical Pathology and Colposcopy (IFCPC) terminology, settings with better resources to manipulate the cervix for a better view of the endocervical canal may assign patients to different categories from those in low-resource settings during a colposcopic examination. Here, we propose a colposcopic revision to the current IFCPC classification by segregating TZ 2 according to the extent of endocervical involvement and TZ 3 according to whether any attempt is made to open the endocervical canal, if such attempt(s) were successful, and the extent to which the practitioner can visualise parts of the uterine cervix beyond the border of the SCJ in the endocervical canal. In this proposed reclassification, TZ 2A has no part of the SCJ extending beyond 5 mm into the endocervical canal, whereas TZ 2B has part or all of the SCJ extending beyond 5 mm into the endocervical canal. TZ 3 is further subclassified into TZ 3A if the practitioner does not attempt to open the endocervical canal or the endocervical canal is opened, but not beyond 5 mm and TZ 3B if the full circumference cannot be visualised after opening the endocervical canal beyond 5 mm. We believe this revision will improve and better standardise the classification of TZ types, with huge implications for practice in low-resource settings, due to limited options for referral and treatment, to reduce the risk of missed cervical cancers and suboptimal treatment resulting from ablating lesions that extend too far into the endocervical canal.

Rate of Involved Endocervical Margins According to High-Risk Human Papillomavirus Subtype and Transformation Zone Type in Specimens with Cone Length ≤ 10 mm versus > 10 mm-A Retrospective Analysis

The aim of this study was to evaluate the endocervical margin status according to transformation zone (TZ) and high-risk HPV (hr-HPV) subtype in specimens with cone length ≤ 10 mm versus > 10 mm to provide data for informed decision making and patients counseling especially for women wishing to conceive. In this retrospective cohort study, 854 patients who underwent large loop excision of the transformation zone during a nine-year period (2013-2021) for cervical disease were analyzed. The main outcome parameters were excision length, histological result, TZ type, HPV subtype and endocervical margin status. A subgroup analysis was performed according to excision length, with a cut-off value of 10 mm. A two-step surgical procedure was performed in case of an excision length of > 10 mm. The overall rate of positive endocervical margins irrespective of excision length was 17.2%, with 19.3% in specimens with ≤ 10 mm and 15.0% with > 10 mm excision length. Overall, 41.2% of women with a visible TZ and HPV 16/hr infection and 27.0% of women with HPV 18 received an excisional treatment of > 10 mm length without further oncological benefit, respectively. In contrast, assuming that only an excision of ≤ 10 mm length had been performed in women with visible TZ, the rate of clear endocervical margins would have been 63.7% for HPV 16/hr infections and 49.3% for HPV 18 infections. In conclusion, the decision about excision length should be discussed with the patient in terms of oncological safety and the risk of adverse pregnancy events. An excision length > 10 mm increases the number of cases with cervical tissue removed without further oncological benefit, which needs to be taken into account in order to provide an individual therapeutic approach. Furthermore, HPV 18 positivity is related to a higher rate of positive endocervical margins irrespective of TZ.

Methylated ZNF582 as a triage marker for occult cervical cancer and advanced cervical intraepithelial neoplasia

Aim: To explore the appropriate triage methods for women infected with high-risk human papillomavirus (hrHPV). Materials & methods: A total of 424 out of 872 hrHPV-infected women were divided into cervicitis (n = 123), cervical intraepithelial neoplasia grade 1 (CIN1; n = 89), CIN2 (n = 72), CIN3 (n = 87) and cervical cancer (n = 53) groups. Results: The sensitivity/specificity of ZNF582^m, PAX1^m and liquid-based cytology (LBC) for hrHPV-infected women with transformation zone 3 CIN3+ was 83.9/93.1, 77.4/90.6 and 80.6/58.5%, respectively. The ZNF582^m/PAX1^m test had a higher specificity than LBC (p < 0.001) and similar sensitivity to that observed for LBC (p > 0.05). ZNF582^m/PAX1^m improved the positive predictive value of CIN3+ (64.7/60.0%) in low-grade LBC (negative predictive value: 91.7/88.7%). Conclusion: ZNF582^m was superior to PAX1^m and LBC tests in detecting CIN3+ in hrHPV-infected women.

Improving colposcopic accuracy for cervical precancer detection: a retrospective multicenter study in China

Background

Colposcopy alone can result in misidentification of high-grade squamous intraepithelial or worse lesions (HSIL +), especially for women with Type 3 transformation zone (TZ) lesions, where colposcopic assessment is particularly imprecise. This study aimed to improve HSIL + case identification by supplementing referral screening results to colposcopic findings.

Methods

This is an observational multicenter study of 2,417 women, referred to colposcopy after receiving cervical cancer screening results. Logistic regression analysis was conducted under uni- and multivariate models to identify factors which could be used to improve HSIL + case identification. Histological diagnosis was established as the gold standard and is used to assess accuracy, sensitivity, and specificity, as well as to incrementally improve colposcopy.

Results

Multivariate analysis highlighted age, TZ types, referral screening, and colposcopists’ skills as independent factors. Across this sample population, diagnostic accuracies for detecting HSIL + increased from 72.9% (95%CI 71.1–74.7%) for colposcopy alone to 82.1% (95%CI 80.6–83.6%) after supplementing colposcopy with screening results. A significant increase in colposcopic accuracy was observed across all subgroups. Although, the highest increase was observed in women with a TZ3 lesion, and for those diagnosed by junior colposcopists.

Conclusion

It appears possible to supplement colposcopic examinations with screening results to improve HSIL + detection, especially for women with TZ3 lesions. It may also be possible to improve junior colposcopists’ diagnoses although, further psychological research is necessary. We need to understand how levels of uncertainty influence diagnostic decisions and what the concept of “experience” actually is and what it means for colposcopic practice.