Histology Findings after Two Years of Cytology/HPV Co-Testing in Germany

Introduction

Since 1 January 2020, diagnostic confirmation of abnormalities detected in the context of cytology/HPV co-testing in cervical cancer screening under the statutory health insurance scheme in women aged 35 and over has been performed according to predefined algorithms. A colposcopy is indicated even in the case of borderline/low-grade cytological changes and/or HPV persistence. In this article we compare the histology findings after primary screening examinations in 2020/21 with those from 2018/19, thus also comparing the results of two different screening approaches.

Patients and Methods

Our analysis included all of the cytology, HPV, and histology results from all primary screening examinations, as well as the resulting diagnostic confirmation and curative cases, that could be obtained by 30 June 2023. In 2018/19 these comprised 650600 cytology and 1804 histology findings, and in 2020/21 there were 491450 cytology and 7156 histology findings. The absolute numbers of histology findings and the percentage ratios of these to all cytological diagnoses are presented with comparison factors.

Results

In 2020/21 there were 5.2 times more histology findings in relation to all previous cytology examinations than in 2018/19, as well as 10.6 times more biopsies, 3.8 times more conizations, and 1.2 times more hysterectomies. There was a particularly high increase in diagnostic confirmation of borderline/low-grade or only HPV-positive findings. With co-testing, 12.7 times more CIN1, 6.4 times more CIN2, and 3.5 times more CIN3 lesions were diagnosed. The proportion of biopsies without dysplasia was 7.6 times higher than in previous years. Cervical carcinomas were diagnosed 1.8 times more frequently, and endometrial carcinomas 0.7 times less frequently.

Conclusion

More CIN lesions were found with co-testing, but the increase in histology findings of low-grade or no dysplasia was far greater than findings of CIN3. Lesions not requiring treatment accounted for 94.4% of biopsy results in 2020/21. The use of computer-assisted LBC with progression markers could reduce this.

Two Years of Cytology and HPV Co-Testing in Germany: Initial Experience

Introduction On 1 January 2020 the screening programme for the prevention of cervical cancer in women from the age of 35 years of the Statutory Health Insurance (GKV) in Germany changed from an annual cytology examination to cytological and HPV co-testing carried out every three years. A large standard diagnostics laboratory has been using liquid-based cytology (LBC) with computer-assisted screening (CAS) since 1 January 2020 to assess the samples.

Patients and Methods The cytological and HPV results for all cases examined with co-testing from 01.01.2020 to 31.12.2021 (n = 395759) are reported and the cytology results obtained using co-testing are compared with the results obtained using only conventional primary cytology screening from the two previous years (n = 588192). Cytology tests were carried out using LBC and computer-assisted screening. A DNA PCR test which can identify 14 types of HPV was used for HPV testing. The cytology results are reported using the Munich Nomenclature III, which is mandatory in Germany, and converted to The Bethesda System (TBS). Problems occurring during the implementation phase are described here.

Results A total of 983951 cases who had primary screening between 01.01.2018 and 31.12.2021 were analysed. The HR HPV-positive rate with co-testing for all age groups was 6.41%. Of this group, 16.31% were positive for HPV-16, 4.43% for HPV-18, and 71.40% had one or more of the other 12 HR HPV types. Several different HPV types were identified in 7.86% of cases. The HPV-positive rate for cases with unremarkable cytological findings was 4.03%. 0.46% of tests were technically invalid. The results of primary cytology screening for 2020/21 (LBC) were: Pap 0 (TBS: unsatisfactory) 0.09%, Pap I and Pap II-a (NILM) 96.82%, Pap II-p/g (~ASC-US/AGC) 1.23%, Pap III-p/g (~ASC-H/AGC) 0.19%, Pap III D1 (LSIL) 1.08%, Pap III D2 (HSIL) 0.31%, Pap IVa/b-p/g (HSIL/AIS) 0.18%, and Pap V-p/g (carcinoma) 0.01%. The rates for 2018/19 (conventional cytology without routine testing for HPV) were significantly higher for Pap II-p/g (1.64%) and significantly lower for Pap III-p/g (0.13%), Pap III D1 (0.45%), Pap III D2 (0.10%) and Pap IVa/b-p/g (0.05%).

Conclusion Evaluation of the data for the two first years of cytology and HPV co-testing from a standard diagnostics laboratory found low HR HPV-positive rates. As regards the cytology tests, the Pap II-p/g rate was significantly lower and the ≥ Pap III rate was significantly higher compared to the two previous years. This points to a probable higher sensitivity and specificity of the new method.

Performance of a DNA methylation marker panel using liquid-based cervical scrapes to detect cervical cancer and its precancerous stages

Background

A change of cervical cancer screening algorithms to an HPV-based screening setting is discussed in many countries, due to higher sensitivity of HPV testing compared to cytology. Reliable triage methods are, however, an essential prerequisite in such a setting to avoid overtreatment and higher screening costs.

Results

In this study, a series of cervical scrapes collected in PreservCyt liquid-based cytology (LBC) medium from women with cervical cancer (n = 5), cervical intraepithelial neoplasia grade 1–3 (n = 74), and normal cytology (n = 201; further n = 352 collected in SureThin®) were assessed for methylation of the marker regions ASTN1, DLX1, ITGA4, RXFP3, SOX17, and ZNF671 using the GynTect assay and compared to cobas® HPV and CINtec Plus® biomarker results. All samples from women with cervical cancer, 61.2% of CIN3, 44.4% of CIN2 and 20.0% of CIN1 cases were scored positive for the GynTect methylation assay. In contrast, all CIN, irrespective of severity grade, and carcinomas were positive by both, CINtec Plus and cobas HPV. The specificity of GynTect for CIN3+ was 94.6% compared to 69.9% for CINtec Plus and 82.6% for cobas HPV (all HPV types) and 90.6% for cobas HPV 16/18. DNA methylation analysis of this methylation marker panel (GynTect assay) in cervical scrapes consistently detects cervical cancer and the majority of CIN3 as well as a subset of CIN1/2 lesions. The detection rate among cytologically normal samples is extraordinarily low (1.5%).

Conclusion

GynTect shows excellent performance when using cervical scrape material collected in liquid-based cytology media, a prerequisite for employing such a test as a triage in screening programs. Compared to the other test systems used in this work, GynTect showed higher specificity while still detecting all cancer cases.