Digital Colposcopy With Dynamic Spectral Imaging for Detection of Cervical Intraepithelial Neoplasia 2+ in Low-Grade Referrals: The IMPROVE-COLPO Study

Agreement on Lesion Presence and Location at Colposcopy

OBJECTIVES/PURPOSE

The reproducibility and sensitivity of image-based colposcopy is low, but agreement on lesion presence and location remains to be explored. Here, we investigate the interobserver agreement on lesions on colposcopic images by evaluating and comparing marked lesions on digitized colposcopic images between colposcopists.

METHODS

Five colposcopists reviewed images from 268 colposcopic examinations. Cases were selected based on histologic diagnosis, i.e., normal/cervical intraepithelial neoplasia (CIN)1 ( n = 50), CIN2 ( n = 50), CIN3 ( n = 100), adenocarcinoma in situ ( n = 53), and cancer ( n = 15). We obtained digitized time-series images every 7-10 seconds from before acetic acid application to 2 minutes after application. Colposcopists were instructed to digitally annotate all areas with acetowhitening or suspect of lesions. To estimate the agreement on lesion presence and location, we assessed the proportion of images with annotations and the proportion of images with overlapping annotated area by at least 4 (4+) colposcopists, respectively.

RESULTS

We included images from 241 examinations (1 image from each) with adequate annotations. The proportion with a least 1 lesion annotated by 4+ colposcopists increased by severity of histologic diagnosis. Among the CIN3 cases, 84% had at least 1 lesion annotated by 4+ colposcopists, whereas 54% of normal/CIN1 cases had a lesion annotated. Notably, the proportion was 70% for adenocarcinoma in situ and 71% for cancer. Regarding lesion location, there was no linear association with severity of histologic diagnosis.

CONCLUSION

Despite that 80% of the CIN2 and CIN3 cases were annotated by 4+ colposcopists, we did not find increasing agreement on lesion location with histology severity. This underlines the subjective nature of colposcopy.

Analysis of New Colposcopy Techniques in the Diagnosis and Evolution of SIL/CIN: Comparison of Colposcopy with the DSI System (COLPO-DSI Study)

Compared with conventional colposcopy, colposcopy assisted by DSI-map increases the detection of HSIL/CIN2+ and might help to identify the lesions more likely to regress.

INTRODUCTION

Comparison of the performance of colposcopy assisted by dynamic spectral imaging (C-DSI) with that of conventional colposcopy (CC) in the diagnosis of cervical intraepithelial neoplasia (HSIL/CIN2 or CIN3).

MATERIALS AND METHODS

A total of 1655 women were referred for colposcopy between 2012 and 2020 and included in the study. Of that total, 973 were examined by the same colposcopist with C-DSI, and 682 with CC. Comparisons between CC and C-DSI were made by using the histological diagnosis performed with a punch biopsy or loop electrosurgical excision procedure (LEEP) as the gold standard. A follow-up study was conducted until 2021 to detect progression to HSIL/CIN2 at 6, 12 and 24 months after first examination.

RESULTS

C-DSI provided higher sensitivity for the diagnosis of HSIL/CIN2 or CIN 3 than CC (sensitivity of 76.8% and 86.6% vs. 54.2% and 72.2%, respectively). In negative or ASCUS/LSIL Pap smear results, C-DSI showed higher sensitivity than CC (sensitivity of 66.7% and 61.5% vs. 21.4% and 33.3%, respectively). In contrast, these differences were not observed in high-grade Pap smears. The sensitivity of C-DSI in cases with HPV16/18 infection was stronger than that of CC (73.53% vs. 56.67%). The sensitivity of C-DSI to detect the progression to HSIL/CIN2+ during follow-up was 30, 17.6 and 35.7% at 6, 12 and 24 months, respectively.

CONCLUSIONS

The present study shows that C-DSI in women referred for colposcopy increases the HSIL/CIN 2-3 detection rate compared to conventional colposcopy. Nevertheless, C-DSI does not seem to be an important tool to predict the evolution of the lesions during follow-up.

European consensus statement on expert colposcopy

BACKGROUND

Following the publication of the European consensus statement on standards for essential colposcopy in 2020, the need for standards relating to more complex and challenging colposcopy practice was recognised. These standards relate to colposcopy undertaken in patients identified through cervical screening and tertiary referrals from colposcopists who undertake standard colposcopy only. This set of recommendations provides a review of the current literature and agreement on care for recognised complex cases. With good uptake of human papillomavirus (HPV) immunisation, we anticipate a marked reduction in cervical disease over the next decade. Still, the expert colposcopist will continue to be vital in managing complex cases, including previous cervical intraepithelial neoplasia (CIN)/complex screening histories and multi-zonal disease.

AIMS

To provide expert guidance on complex colposcopy cases through published evidence and expert consensus.

MATERIAL & METHODS

Members of the EFC and ESGO formed a working group to identify topics considered to be the remit of the expert rather than the standard colposcopy service. These were presented at the EFC satellite meeting, Helsinki 2021, for broader discussion and finalisation of the topics.

RESULTS & DISCUSSION

The agreed standards included colposcopy in pregnancy and post-menopause, investigation and management of glandular abnormalities, persistent high-risk HPV+ with normal/low-grade cytology, colposcopy management of type 3 transformation zones (TZ), high-grade cytology and normal colposcopy, colposcopy adjuncts, follow-up after treatment with CIN next to TZ margins and follow-up after treatment with CIN with persistent HPV+, and more. These standards are under review to create a final paper of consensus standards for dissemination to all EFC and ESGO members.

Comparison of accuracy and reproducibility of colposcopic impression based on a single image versus a two-minute time series of colposcopic images

OBJECTIVE

Colposcopy is an important part of cervical screening/management programs. Colposcopic appearance is often classified, for teaching and telemedicine, based on static images that do not reveal the dynamics of acetowhitening. We compared the accuracy and reproducibility of colposcopic impression based on a single image at one minute after application of acetic acid versus a time-series of 17 sequential images over two minutes.

METHODS

Approximately 5000 colposcopic examinations conducted with the DYSIS colposcopic system were divided into 10 random sets, each assigned to a separate expert colposcopist. Colposcopists first classified single two-dimensional images at one minute and then a time-series of 17 sequential images as 'normal,' 'indeterminate,' 'high grade,' or 'cancer'. Ratings were compared to histologic diagnoses. Additionally, 5 colposcopists reviewed a subset of 200 single images and 200 time series to estimate intra- and inter-rater reliability.

RESULTS

Of 4640 patients with adequate images, only 24.4% were correctly categorized by single image visual assessment (11% of 64 cancers; 31% of 605 CIN3; 22.4% of 558 CIN2; 23.9% of 3412 < CIN2). Individual colposcopist accuracy was low; Youden indices (sensitivity plus specificity minus one) ranged from 0.07 to 0.24. Use of the time-series increased the proportion of images classified as normal, regardless of histology. Intra-rater reliability was substantial (weighted kappa = 0.64); inter-rater reliability was fair ( weighted kappa = 0.26).

CONCLUSION

Substantial variation exists in visual assessment of colposcopic images, even when a 17-image time series showing the two-minute process of acetowhitening is presented. We are currently evaluating whether deep-learning image evaluation can assist classification.

Value of colposcopy with dynamic spectral imaging in the detection and evolution of high-grade cervical lesions

OBJECTIVE

To analyze the performance of colposcopy assisted with dynamic spectral imaging (CC-DSI) compared to conventional colposcopy (CC) in diagnosing cervical intraepithelial neoplasia 2+ (CIN2+).

METHODS

: 973 consecutive women were referred for colposcopy between 2012 and 2016 and were examined simultaneously by CC and CC-DSI; 877 were eligible. Comparisons between CC and CC-DSI were performed against the histological diagnosis performed by either punch biopsy or loop electrosurgical excision procedure (LEEP).

RESULTS

: In final histology, 494 women had no CIN, 250 had CIN1 and 133 had CIN2+. The sensitivity to identify women with CIN2+ was significantly higher for CC-DSI compared to CC for the entire group and in the subgroup of 675 women referred with ASCUS or LSIL. In women with HPV16/18 infections, the sensitivity of CC increased with the addition of DSI from 53% to 79% (p<0.001). Using a multivariant Cox regression model, CC-DSI was an independent factor for progression of the cervical lesions (HR: 2.29, 95%CI 1.07-4.90). Other predictive factors were the number of sexual partners (HR: 1.05, 95%CI: 1.01-1.09) and anal intercourse (HR: 2.45, 95%CI 1.23-5.02).

CONCLUSION

CC-DSI improves the ability to detect cervical lesions compared to CC and could help predict their potential to progress.

Visual appearance of the uterine cervix differs on the basis of HPV type status in high-grade squamous intraepithelial lesion: the results of a reliable method

Background

This study aimed to evaluate the differences in cervical appearance among different human papillomavirus (HPV) genotypes in patients with high-grade squamous intraepithelial lesions (HSILs).

Methods

A total of 239 histopathological HSIL patients were included and divided into eight groups on the basis of HPV genotype in this prospective study. We present a reliable imaging method that provides reproducible, sensitive and unbiased assessments of cervical appearance characteristics. Colorimetric and morphometric data of colposcopic patterns after the application of acetic acid and iodine were acquired using ImageJ software and the surrounding normal regions were used as controls.

Results

The differences in red, green, blue and mean greyscale values in acetowhite epithelium obtained from ImageJ were not significant between the HPV16 and HPV18 groups (P < 0.05). The differences in red, green, and mean greyscale values in iodine staining were significant between the HPV18 and the other groups (P < 0.05). The frequency of the occurrence of the coarse mosaic patterns was significantly different among groups (P < 0.05), reducing in sequence were the HPV16, HPV-negative, HPV18, HPV31/33 and HPV52/58 groups. For the lesion area of HSILs, the HPV-negative group was the largest. The sensitivity of colposcopic impression varied among HPV genotypes (P < 0.01), being lowest in the HPV52 group.

Conclusions

Although being nonspecific, iodine negativity should be concerned in HPV18-positive lesions which is closely related to glandular epithelium. Vascular patterns in HPV52/58-positive HSIL are quite occult and tend to be missed by colposcopists. HPV-negative lesions are prone to be large and present typical vascular patterns despite being rare.

Using Dynamic Features for Automatic Cervical Precancer Detection

Cervical cancer remains a major public health concern in developing countries due to financial and human resource constraints. Visual inspection with acetic acid (VIA) of the cervix was widely promoted and routinely used as a low-cost primary screening test in low- and middle-income countries. It can be performed by a variety of health workers and the result is immediate. VIA provides a transient whitening effect which appears and disappears differently in precancerous and cancerous lesions, as compared to benign conditions. Colposcopes are often used during VIA to magnify the view of the cervix and allow clinicians to visually assess it. However, this assessment is generally subjective and unreliable even for experienced clinicians. Computer-aided techniques may improve the accuracy of VIA diagnosis and be an important determinant in the promotion of cervical cancer screening. This work proposes a smartphone-based solution that automatically detects cervical precancer from the dynamic features extracted from videos taken during VIA. The proposed solution achieves a sensitivity and specificity of 0.9 and 0.87 respectively, and could be a solution for screening in countries that suffer from the lack of expensive tools such as colposcopes and well-trained clinicians.

Dynamic Spectral Imaging Colposcopy Versus Regular Colposcopy in Women Referred With High-Grade Cytology: A Nonrandomized Prospective Study

OBJECTIVE

The aim of the study was to evaluate the sensitivity of dynamic spectral imaging (DSI) colposcopy compared with regular colposcopy for women referred with high-grade cervical cytology.

METHODS

In a prospective, nonrandomized, multicenter study, we included women referred for colposcopy at hospital gynecology clinics with high-grade cytology. Women were examined using either a regular or DSI colposcope. In both groups, colposcopists located 1 area viewed as most suspicious. In the DSI group, this was done before viewing the DSI map. Subsequently, an area was chosen based on the worst color of the DSI map, and further additional biopsies were taken. All women had 4 cervical biopsies taken, all analyzed separately. The main outcome was sensitivity to find cervical intraepithelial neoplasia grade 2 or worse (CIN2+).

RESULTS

A total of 261 women were examined using DSI colposcopy, and 156 women were examined using regular colposcopy. The sensitivity for finding CIN2+ when using the DSI technology as an adjunctive technology was found to be 82.2% (95% CI = 75.9-87.4), based on an average of 1.4 biopsies. This was corresponding in sensitivity to 2 biopsies taken using regular colposcopy (80.3%; 95% CI = 72.3-86.8). There was no difference in sensitivity for CIN+ between the groups when 3 or more biopsies were taken.

CONCLUSIONS

We found that the DSI colposcope may help direct biopsy placement; however, the improvement is based on small differences in needed biopsies and the clinical significance of this may be small. Multiple biopsies were still superior.

Can the dynamic spectral imaging (DSI) color map improve colposcopy examination for precancerous cervical lesions? A prospective evaluation of the DSI color map in a multi-biopsy clinical setting

Background

Colposcopy serves as a subjective examination of the cervix with low sensitivity to detect cervical intraepithelial dysplasia (CIN) grade 2 or worse (CIN2 +). Dynamic spectral imaging (DSI) colposcopy has been developed to provide an objective element to cervix examinations and has been proven to increase sensitivity of detecting CIN2 + . We aimed to assess the performance of the DSI color map and compared it to histological diagnoses of cervical biopsies in determining the CIN grade present.

Methods

Women were included in a consecutive, prospective manner at Randers Regional Hospital, Denmark. Women were eligible to participate if they were referred for colposcopy due to abnormal cervical smear (threshold:  ≥ ASCUS) or follow-up after previously diagnosed CIN. All women had four biopsies taken, one directed by colposcopists alone prior to viewing the DSI color map, one directed by the worst color on the respective DSI color map, and two additional biopsies. All biopsies were analyzed separately. We calculated sensitivity, specificity, positive predictive values, and negative predictive values (NPVs) with 95% confidence intervals (CIs).

Results

A total of 800 women were recruited. Of these, 529 (66.1%) were eligible for inclusion. The sensitivity of the DSI color map was found to be 48.1% (95% CI 41.1–55.1) in finding CIN grade 2 or worse (CIN2 +) when compared to the histological diagnosis of the DSI directed biopsy. This was 42.5% (95% CI 36.7–48.5) when compared to the final histological diagnosis of all four cervical biopsies and with an NPV of 53.5% (95% CI 50.5–56.5).

Conclusion

The worst color indicated by the DSI map might not consistently reflect the true grade of cervical dysplasia present. Thus, even though the DSI color map indicates low-grade changes, colposcopists should still consider taking biopsies from the area as high-grade changes might be present.

Trial registration: NCT04249856, January 31 2020 (retrospectively registered).

Rate of detecting CIN3+ among patients with ASC-US using digital colposcopy and dynamic spectral imaging

The present study compared two methods for the detection of severe cervical dysplasia in women with atypical squamous cells of underdetermined significance (ASC-US) cytology; digital colposcopy with adjunctive dynamic spectral imaging (DSI) and conventional colposcopy. IMPROVE-COLPO was a two-arm cross-sectional study of US community-based colposcopy. The active (prospective) arm of this study recruited patients examined by digital colposcopy and adjunctive DSI. Preceding consecutive patients that had been examined with conventional methods were used as historical controls in the retrospective arm of the study after being matched in number to those in the prospective arm by a colposcopist. In the present study, the primary measure was the number of women detected with cervical intraepithelial neoplasia (CIN) grade 3 or worse (CIN3+) following punch biopsy. The study included 1,353 retrospective and 1,226 prospective patients eligible for this analysis who were examined by 146 colposcopists in 42 community-based clinics. The patient baseline characteristics were comparable between the two arms. The average number of biopsies taken per patient was higher among the prospective arm patients (including standard and DSI-assisted biopsies) compared with the retrospective arm control patients (1.21 vs. 0.97 respectively). Biopsy detected 31 patients with CIN3+ [2.29%; 95% confidence interval (CI), 1.56-3.24] in the retrospective arm, and 48 patients with CIN3+ (3.92%; 95% CI, 2.90-5.16) in the prospective arm. The difference in the number of patients detected with CIN3+ in the two arms of the study was 1.62% (95% CI, 0.30-3.04; P=0.022), which corresponds to a 70.9% relative increase in the prospective compared with the retrospective arm. Biopsy appeared less efficient in detecting patients with CIN3+ in the retrospective arm compared with the prospective arm. However, there was no statistically significant difference between the retrospective arm and the prospective arm in terms of: i) Biopsies taken (over the entire population) per patient detected with CIN3+ (42.2 in the retrospective arm vs. 30.8 in the prospective arm; P=0.164) and ii) positive predictive value of using biopsies to identify patients with CIN3+ (2.83 vs. 3.92; P=0.118). Adoption of digital colposcopy with DSI increased the number of biopsies collected from ASC-US patients compared with retrospective controls of standard colposcopy and detected a significantly higher number of patients who were CIN3+. The number of additional biopsies taken in the prospective arm compared with the retrospective arm was too small to explain the increased detection of patients with CIN3+ observed in the prospective arm, suggesting that biopsies in the prospective arm were better at identifying CIN3+.

The impact of age and high-risk human papillomavirus (hrHPV) status on the prevalence of high-grade cervical intraepithelial neoplasia (CIN2+) in women with persistent hrHPV-positive, cytology-negative screening samples: a prospective cohort study

OBJECTIVE

To establish the prevalence of high-grade cervical intraepithelial neoplasia (CIN2+) in women referred to colposcopy with persistent high-risk human papillomavirus (hrHPV) cytology-negative screening sample according to hrHPV genotype, age at referral and colposcopic performance.

DESIGN

Prospective cohort study.

SETTING

Single colposcopy clinic linked to a population-based screening programme.

POPULATION

Women referred with persistent hrHPV cytology-negative routine screening samples.

METHODS

Prospective study with descriptive statistics from a single colposcopy unit between June 2014 and July 2019.

MAIN OUTCOME MEASURES

Prevalence of hrHPV genotypes and CIN2+, positive predictive value for colposcopic impression, and inadequate colposcopic examinations.

RESULTS

A total of 3107 women were referred. Prevalence of CIN2+ was highest for persistent HPV16 infections (10.7%) compared with HPV18 (3.6%) or HPVO (4.7%). Prevalence of CIN2+ declined with age (25-34 years 14.2% to 55-64 years 1.1%) whereas the percentage of women with an inadequate colposcopic examination increased (25-34 years 0.9% to 55-64 years 29.5%). High-grade colposcopic impression fell over time during the study from 16.1 to 5.1%. The positive predictive value for colposcopic impression of CIN2+ was affected by hrHPV genotype (57.3% for HPV16 versus 32.1% for nonHPV16). The adjunctive use of electrical impedance spectroscopy detected an extra 42 cases of CIN2+, which was irrespective of hrHPV genotype.

CONCLUSIONS

Primary hrHPV cervical screening increases detection of CIN2+; however, low specificity results in more women being referred to colposcopy with a low prevalence of CIN2+. Colposcopy performs poorly in some groups, particularly with HPVO infections and women over 50 years of age. An appropriate threshold for referral to colposcopy in primary hrHPV screening has not been established.

TWEETABLE ABSTRACT

Low prevalence of CIN2+ in HPV-positive negative cytology samples. HPV genotype, age and prevalence of CIN2+ affect colposcopic performance.

Accuracy of colposcopy-directed biopsy vs dynamic spectral imaging directed biopsy in correctly identifying the grade of cervical dysplasia in women undergoing conization: A methodological study

INTRODUCTION

Dynamic spectral imaging (DSI) colposcopy has previously been found to improve sensitivity of CIN2+ detection. The aim of this study was to compare the histological diagnosis of colposcopic-directed biopsies (CDB) with that of DSI-directed biopsies in women undergoing conization, using the histological diagnosis of the conization specimen as gold standard.

MATERIAL AND METHODS

Women referred for colposcopy were included in a prospective cohort study at Randers Regional Hospital, Denmark, from January 2016 to February 2019. All women had four cervical punch biopsies taken. The first biopsy was taken from the area that appeared most abnormal by conventional colposcopy (ie, CDB) and the second biopsy from the area that appeared most abnormal using the DSI map. An additional two biopsies were taken either from other visible lesions or as random biopsies. Biopsies were analyzed separately. If any biopsies revealed cervical dysplasia of such a degree that excisional treatment was recommended, the patient was referred for conization. Subsequently, we compared the histological diagnosis of CDB and DSI-directed biopsies with that of the cone biopsy.

RESULTS

A total of 573 women were enrolled, 170 of which underwent conization. In women with an adequate colposcopy and representative biopsies (n = 124) there was an overall agreement rate between the worst biopsy diagnosis (of any four) and the conization diagnosis in 95.2% (95% CI 89.8-98.2) of women. CDB diagnosis agreed with the cone diagnosis in 80.6% (95% CI 72.6-87.2) of women. DSI-directed biopsy agreed with the cone diagnosis in 83.9% (95% CI 76.2-89.9) of women. The difference in detection rate between the CDB and the DSI-directed biopsy was, however, not significant (P = .54). Taking four biopsies increases the detection rate of cervical dysplasia to 95.2%, which was a significant increase from both CDB alone (P = .0008) and DSI-directed biopsy alone (P = .0053).

CONCLUSIONS

We found no significant difference in the ability to identify the cervical dysplasia grade between CDB and DSI-directed biopsies. A higher detection rate of cervical dysplasia was achieved with four biopsies than with one CDB biopsy or one DSI-directed biopsy.

Observed Colposcopy Practice in US Community-Based Clinics: The Retrospective Control Arm of the IMPROVE-COLPO Study

Objective:

The aim of the study was to characterize colposcopy practice and management of women with cervical abnormalities in US community-based clinics.

Materials and Methods:

IMPROVE-COLPO was a 2-arm study of colposcopy patients with an abnormal screening result. The prospective arm recruited women to undergo examination with a commercial digital colposcope. The retrospective-control arm collected data (chart review) from previous colposcopies performed using standard equipment and methods. From the retrospective arm, we analyzed referral trends, colposcopy and biopsy practice, and management patterns.

Results:

We collected data of 3,602 eligible women (median age = 34 years) that had been examined from 2012 to 2017 by 154 colposcopists at 44 clinics across 12 states. Most patients were premenopausal (87.9%), privately insured (88.2%), and had a low-grade (low-grade squamous intraepithelial lesion/atypical squamous cells of undetermined significance/human papillomavirus positive) indication (87.2%). Most colposcopists performed less than 3 colposcopies monthly and their biopsy rate was1.47 biopsies/patient for high-grade referrals and 0.97 for low-grade referrals (p < .001). Random biopsy was rare (0.4% of biopsies). Most women(74.9%) underwent endocervical sampling, including 62.5% of women aged 21 to 24 years. Colposcopic impression was frequently not reported(58.8%), and its sensitivity to predict histology-confirmed cervical intraepithelial neoplasia (CIN) 2+ as “high-grade” was 56.5% for high-grade referrals and 23.2% for low-grade referrals. Excisions often (44.5%) returned <CIN 2, including patients aged 21–40 years (37.4%).

Conclusions:

In this analysis, most colposcopists performed few colposcopies and took less than 2 biopsies per patient. Colposcopic impression had a poor sensitivity to predict histology-confirmed CIN 2+. Although recent research indicates that taking multiple biopsies improves sensitivity and detection of CIN 2+, this is not being practiced in the US.