Advances in colposcopy: new technologies to challenge current practice

Diagnostic comparison of electrical impedance spectroscopy with colposcopy and HPV mRNA-testing in the prediction of CIN2+ women in Greece

AIM

To compare the diagnostic parameters of electrical impedance spectroscopy (EIS) via ZedScan, a device that measures spectra to differentiate between normal and abnormal cervical tissues, when used as an adjunct to colposcopies in the diagnosis of HSILs/CIN2+ in Greek women with abnormal referral cytology toward colposcopy alone and HPV mRNA-testing.

METHODS

This study analyzed 86 women, patients of the Colposcopy and Cervical Pathology Clinic of 2nd Obstetrics and Gynecology Department, Aristotle University of Thessaloniki at Hippokration General Hospital, between January 2022 and September 2022. During the visits, women were subjected to cytology, colposcopy alone and then with EIS/ZedScan and histological sampling.

RESULTS

Common use of colposcopies and EIS/ZedScan allowed detecting an additional 14 cases of CIN2+ (16.2%) that colposcopy alone failed to report. EIS enhanced the sensitivity of colposcopy from 80.65% to 100% equal with that of HPV-mRNA test while retaining a high specificity (94.74%) which is much higher than specificity of HPV mRNA-testing (65.45%). EIS-assisted colposcopy had the highest value combination of positive and negative predictive values (96.15% and 100%) compared to colposcopy alone (100% and 75%) and HPV mRNA-testing (72.46% and 100%).

CONCLUSIONS

Colposcopies performed with EIS/ZedScan demonstrated effectiveness in the diagnosing of CIN2+ leading to a significant increase in the number of CIN2+ that would have been missed if only colposcopy was applied especially in women with LSIL referral cytology. EIS/ZedScan seems to possess the ideal diagnostic threshold for sensitivity, specificity, and predictive values for CIN2+ compared to colposcopy alone and HPV mRNA-testing.

200 years of diagnosis and treatment of cervical precancer

OBJECTIVES

The history of the diagnosis and treatment of cervical precancer is fragmentary. Findings in the English-speaking and German-speaking areas vary considerably. We aim to describe the history of clinical advances in diagnosis and treatment of cervical precancer and identify areas where further work is required.

STUDY DESIGN

We conducted a search of PubMed and Google Scholar. Full article texts were reviewed. Reference lists were screened for additional articles and books. 9 basic articles in German and 13 basic articles in books were identified.

RESULTS

The first images of the ectocervix were published by H. Lebert (1812-1879) in the middle of the nineteenth century. R. Meyer's (1864-1947) theory of erosions, which dominated cervical pathology in the nineteenth century, was later refuted in studies by C. A. Ruge (1846-1926) and J. Veit (1852-1917). In 1908 W. Schauenstein (1870-1943) recognized the step-by-step development of cervical cancer. H. Hinselmann (1884-1959) replaced the purely histopathological approach previously with the use of colposcopy. All conization methods applied today can be traced back to amputation of the ectocervix as first indicated by J. Marion Sims (1813-1883) in 1861. In 1928 M. N. Hyams was the first to describe an excision method that employed electrodiathermy. The method of cold knife conization is based on a publication by J.W. Scott from 1957. The final breakthrough to effective electrodiathermy was achieved with the publications of W. Prendiville.

CONCLUSIONS

This paper is a step toward a better understanding of what we think and do today based on past findings of colposcopists and gynecopathologists.

Using technology to harmonise treatment approaches in colposcopy in the face of a changing environment

The overall numbers of precancerous lesions are expected to fall as human papillomavirus (HPV) vaccinated women enter the cervical screening programme. Juxtaposed against an increase in referrals from the introduction of primary high-risk HPV screening, colposcopists expect to see a decreasing incidence of high-grade cervical intraepithelial neoplasia (CIN). Correct identification of lesions will become more challenging, as the prevalence of high-grade lesions becomes minimal and conventional colposcopy is subject to a lower sensitivity. In this review, we explore the scenarios where adjunct technologies could support colposcopists to manage referrals and diagnose treatable lesions with more confidence.

POISED-5, a portable on-board electrochemical impedance spectroscopy biomarker analysis device

Point-of-care medical devices offer the potential for rapid biomarker detection and reporting of medical conditions, thereby bypassing the requirements for offline clinical laboratory facilities in many cases. Label-free electrochemical techniques are suitable for use in handheld diagnostic devices due the inherent electronic detection modality and low requirement for processing reagents. While electrochemical impedance sensing is widely used in tissue analysis such as body composition measurement, its use in point-of-care patient testing is yet to be widely adopted. Here we have considered a number of issues currently limiting the translation of electrochemical impedance sensing into clinical biosensor devices. Specifically, we have addressed the current requirement for these sensors to be connected to an external processor by applying a minimum number of frequencies required for optimized biomarker detection, and subsequently delivering analytics within the measurement device. The POISED-5 device was evaluated using a sensor for the ovarian cancer biomarker cancer antigen 125 (CA125), demonstrating performance comparable to standard laboratory equipment, with direct interpretation of response signal amplitude substituting traditional impedance component calculation and model fitting.

Optical techniques for cervical neoplasia detection

This paper provides an overview of the current research in the field of optical techniques for cervical neoplasia detection and covers a wide range of the existing and emerging technologies. Using colposcopy, a visual inspection of the uterine cervix with a colposcope (a binocular microscope with 3- to 15-fold magnification), has proven to be an efficient approach for the detection of invasive cancer. Nevertheless, the development of a reliable and cost-effective technique for the identification of precancerous lesions, confined to the epithelium (cervical intraepithelial neoplasia) still remains a challenging problem. It is known that even at early stages the neoplastic transformations of cervical tissue induce complex changes and modify both structural and biochemical properties of tissues. The different methods, including spectroscopic (diffuse reflectance spectroscopy, induced fluorescence and autofluorescence spectroscopy, Raman spectroscopy) and imaging techniques (confocal microscopy, optical coherence tomography, Mueller matrix imaging polarimetry, photoacoustic imaging), probe different tissue properties that may serve as optical biomarkers for diagnosis. Both the advantages and drawbacks of these techniques for the diagnosis of cervical precancerous lesions are discussed and compared.