Dynamic spectral imaging colposcopy: higher sensitivity for detection of premalignant cervical lesions

Deep Learning Diagnostic Classification of Cervical Images to Augment Colposcopic Impression

OBJECTIVE

A deep learning classifier that improves the accuracy of colposcopic impression.

METHODS

Colposcopy images taken 56 seconds after acetic acid application were processed by a cervix detection algorithm to identify the cervical region. We optimized models based on the SegFormer architecture to classify each cervix as high-grade or negative/low-grade. The data were split into histologically stratified, random training, validation, and test subsets (80%-10%-10%). We replicated a 10-fold experiment to align with a prior study utilizing expert reviewer analysis of the same images. To evaluate the model's robustness across different cameras, we retrained it after dividing the dataset by camera type. Subsequently, we retrained the model on a new, histologically stratified random data split and integrated the results with patients' age and referral data to train a Gradient Boosted Tree model for final classification. Model accuracy was assessed by the receiver operating characteristic area under the curve (AUC), Youden's index (YI), sensitivity, and specificity compared to the histology.

RESULTS

Out of 5,485 colposcopy images, 4,946 with histology and a visible cervix were used. The model's average performance in the 10-fold experiment was AUC = 0.75, YI = 0.37 (sensitivity = 63%, specificity = 74%), outperforming the experts' average YI of 0.16. Transferability across camera types was effective, with AUC = 0.70, YI = 0.33. Integrating image-based predictions with referral data improved outcomes to AUC = 0.81 and YI = 0.46. The use of model predictions alongside the original colposcopic impression boosted overall performance.

CONCLUSIONS

Deep learning cervical image classification demonstrated robustness and outperformed experts. Further improved by including additional patient information, it shows potential for clinical utility complementing colposcopy.

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.

Assessing Inter-Annotator Agreement for Medical Image Segmentation

Artificial Intelligence (AI)-based medical computer vision algorithm training and evaluations depend on annotations and labeling. However, variability between expert annotators introduces noise in training data that can adversely impact the performance of AI algorithms. This study aims to assess, illustrate and interpret the inter-annotator agreement among multiple expert annotators when segmenting the same lesion(s)/abnormalities on medical images. We propose the use of three metrics for the qualitative and quantitative assessment of inter-annotator agreement: 1) use of a common agreement heatmap and a ranking agreement heatmap; 2) use of the extended Cohen's kappa and Fleiss' kappa coefficients for a quantitative evaluation and interpretation of inter-annotator reliability; and 3) use of the Simultaneous Truth and Performance Level Estimation (STAPLE) algorithm, as a parallel step, to generate ground truth for training AI models and compute Intersection over Union (IoU), sensitivity, and specificity to assess the inter-annotator reliability and variability. Experiments are performed on two datasets, namely cervical colposcopy images from 30 patients and chest X-ray images from 336 tuberculosis (TB) patients, to demonstrate the consistency of inter-annotator reliability assessment and the importance of combining different metrics to avoid bias assessment.

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.

Increased detection of high grade CIN, when using electrical impedance spectroscopy as an adjunct to routine colposcopy, is maintained when used across international boundaries: Prospective data from nine European countries

OBJECTIVE

To evaluate the performance of EIS (ZedScan) with colposcopy in the detection of high grade CIN (HG-CIN) in different health care settings.

METHOD

Pooled analysis of data from 26 colposcopy centres in 9 countries. All women underwent colposcopy and ZedScan examination. Data was recorded prospectively via a proforma. Indications for referral to colposcopy were according to national guidelines. Pathology was reported according to national guidelines.

RESULTS

5257 women were examined by 82 colposcopists, median 93 women per centre (range 41 - 2684), 3 users per centre (range 1-8). Referral indications were; 19.3% high grade cytology, 50.4% low grade, 30.3% clinical or HPV positive / cytology negative. The prevalence of HG-CIN was 26.5%; 79.1% in high grade referrals, 16.7% low grade, 9.4% clinical or HPV positive / cytology negative. The use of ZedScan detected an extra 269 cases of high grade CIN (24% increase) (7.5% increase for high grade referrals, 57.9% for low grade and 52% for clinical or HPV positive/cytology negative). Based upon colposcopic impression (CI), the sensitivity of colposcopy for CIN2 + was 74.1% compared with 91.6% for colposcopy with ZedScan (Chi² p < 0.0001). The PPV for a ZedScan directed biopsy varied according to referral cytology and colposcopic impression (19.5% to 85.7%). 489 women underwent treatment at first visit, when ZedScan suggested treatment, 95.1% had HG-CIN/HG-CGIN or cervical cancer. The pooled results for the whole 26 centres were consistent with the results obtained for the largest centre (Sheffield) alone and also with the results with this largest centre excluded.

CONCLUSIONS

The addition of EIS (ZedScan) increases detection of HG-CIN with the PPV for a ZedScan directed biopsy consistent with the published literature. Results were similar in multiple healthcare settings. With more women being referred to colposcopy at low risk of HG-CIN, due to HPV vaccination and primary HPV screening, this study confirms the value of a real time adjunctive technology.

Unsupervised Deep Learning Registration of Uterine Cervix Sequence Images

During a colposcopic examination of the uterine cervix for cervical cancer prevention, one or more digital images are typically acquired after the application of diluted acetic acid. An alternative approach is to acquire a sequence of images at fixed intervals during an examination before and after applying acetic acid. This approach is asserted to be more informative as it can capture dynamic pixel intensity variations on the cervical epithelium during the aceto-whitening reaction. However, the resulting time sequence images may not be spatially aligned due to the movement of the cervix with respect to the imaging device. Disease prediction using automated visual evaluation (AVE) techniques using multiple images could be adversely impacted without correction for this misalignment. The challenge is that there is no registration ground truth to help train a supervised-learning-based image registration algorithm. We present a novel unsupervised registration approach to align a sequence of digital cervix color images. The proposed deep-learning-based registration network consists of three branches and processes the red, green, and blue (RGB, respectively) channels of each input color image separately using an unsupervised strategy. Each network branch consists of a convolutional neural network (CNN) unit and a spatial transform unit. To evaluate the registration performance on a dataset that has no ground truth, we propose an evaluation strategy that is based on comparing automatic cervix segmentation masks in the registered sequence and the original sequence. The compared segmentation masks are generated by a fine-tuned transformer-based object detection model (DeTr). The segmentation model achieved Dice/IoU scores of 0.917/0.870 and 0.938/0.885, which are comparable to the performance of our previous model in two datasets. By comparing our segmentation on both original and registered time sequence images, we observed an average improvement in Dice scores of 12.62% following registration. Further, our approach achieved higher Dice and IoU scores and maintained full image integrity compared to a non-deep learning registration method on the same dataset.

Detection of Host Cell Gene/HPV DNA Methylation Markers: A Promising Triage Approach for Cervical Cancer

Cervical cancer is the most prevalent gynecologic malignancy, especially in women of low- and middle-income countries (LMICs). With a better understanding of the etiology and pathogenesis of cervical cancer, it has been well accepted that this type of cancer can be prevented and treated via early screening. Due to its higher sensitivity than cytology to identify precursor lesions of cervical cancer, detection of high-risk human papillomavirus (HR-HPV) DNA has been implemented as the primary screening approach. However, a high referral rate for colposcopy after HR-HPV DNA detection due to its low specificity in HR-HPV screening often leads to overtreatment and thus increases the healthcare burden. Emerging evidence has demonstrated that detection of host cell gene and/or HPV DNA methylation represents a promising approach for the early triage of cervical cancer in HR-HPV-positive women owing to its convenience and comparable performance to cytology, particularly in LMICs with limited healthcare resources. While numerous potential markers involving DNA methylation of host cell genes and the HPV genome have been identified thus far, it is crucial to define which genes or panels involving host and/or HPV are feasible and appropriate for large-scale screening and triage. An ideal approach for screening and triage of CIN/ICC requires high sensitivity and adequate specificity and is suitable for self-sampling and inexpensive to allow population-based screening, particularly in LMICs. In this review, we summarize the markers of host cell gene/HR-HPV DNA methylation and discuss their triage performance and feasibility for high-grade precancerous cervical intraepithelial neoplasia or worse (CIN2+ and CIN3+) in HR-HPV-positive women.

The detection of cervical neoplasia via optical ımaging: a pilot clinical study

PURPOSE

The present study aims to develop a new high-resolution imaging system for the early diagnosis of cervical neoplasia based on increased vessel density of the cervical tissue.

METHODS

An optical device was developed to obtain high contrast and resolution images of vascular structures of the cervix in the present study. The device utilizes a telecentric lens to capture cervix images under light illumination with a wavelength of 550 nm emitted from LEDs. Images were obtained using the telecentric lens with or without acetic acid application to the cervix. Image processing algorithms were used to contrast and extract the skeleton of the vascular structures on the cervix. In the evaluation of the vascular density, the cervical images were divided into 12 o'clock positions, and the fractal dimension of the vascularity was calculated for each dial area between the o'clock positions. The region with the largest fractal dimension was accepted as the region with the highest probability of lesion. The range of vessel sizes was split into small classes of "bins" for each dial area with the highest fractal dimension. To validate the system's success in differentiating between normal and HSIL lesions, forty five patients who underwent colposcopy and biopsy were included in a pilot study.

RESULTS

The system correctly classified four HSIL cases out of five and failed to detect one HSIL case, achieving an accuracy rate of 97.8% with an 80% sensitivity and 100% specificity.

CONCLUSION

The developed high-resolution optical imaging system may potentially be used in detecting cervical neoplasia just before the biopsy and reduce the number of false-positive cases.

Multi-center clinical study using optical coherence tomography for evaluation of cervical lesions in-vivo

In this prospective study of an in-vivo cervical examination using optical coherence tomography (OCT), we evaluated the diagnostic value of non-invasive and real-time OCT in cervical precancerous lesions and cancer diagnosis, and determined the characteristics of OCT images. 733 patients from 5 Chinese hospitals were inspected with OCT and colposcopy-directed biopsy. The OCT images were compared with the histological sections to find out the characteristics of various categories of lesions. The OCT images were also interpreted by 3 investigators to make a 2-class classification, and the results were compared against the pathological results. Various structures of the cervical tissue were clearly observed in OCT images, which matched well with the corresponding histological sections. The OCT diagnosis results delivered a sensitivity of 87.0% (95% confidence interval, CI 82.2-90.7%), a specificity of 84.1% (95% CI 80.3-87.2%), and an overall accuracy of 85.1%. Both good consistency of OCT images and histological images and satisfactory diagnosis results were provided by OCT. Due to its features of non-invasion, real-time, and accuracy, OCT is valuable for the in-vivo evaluation of cervical lesions and has the potential to be one of the routine cervical diagnosis methods.

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.

Quality Assessment of Endoscopic Forceps Biopsy Samples under Magnifying Narrow Band Imaging for Histological Diagnosis of Cervical Intraepithelial Neoplasia: A Feasibility Study

The current standard for diagnosing cervical intraepithelial neoplasia (CIN) is colposcopy followed by punch biopsy. We have developed flexible magnifying endoscopy with narrow band imaging (ME-NBI) for the diagnosis of CIN. Here, we investigated the feasibility of targeted endoscopic forceps biopsy (E-Bx) under guidance of ME-NBI for the diagnosis of CIN. We prospectively enrolled 32 consecutive patients with confirmed or suspected high-grade CIN undergoing cervical conization. Next to colposcopy, the same patients underwent ME-NBI just before conization. ME-NBI was performed, and 30 E-Bx samples were taken from lesions suspicious for high-grade CIN and 15 from non-suspicious mucosa. We recalled 82 punch biopsy (P-Bx) specimens taken from lesions suspicious for high-grade CIN under colposcopic examination before enrollment. The proportion of sufficient biopsy samples, which had an entire mucosal layer with subepithelial tissue, for the diagnosis of CIN was evaluated by both methods. Performance of targeted E-Bx for the final diagnosis of at least high-grade CIN was calculated. Seventeen P-Bx specimens were unavailable. The proportion of sufficient samples with E-Bx was 84%, which was similar to that with P-Bx (87%) (p = 0.672). The sensitivity, specificity, and accuracy of ME-NBI using E-Bx was 92%, 81%, and 88%, respectively. In conclusion, ME-NBI-guided E-Bx samples were feasible for histological diagnoses of CIN, and further investigation of its diagnostic accuracy is warranted.

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).

Factors Correlated with the Accuracy of Colposcopy-Directed Biopsy: A Systematic Review and Meta-Analysis

PURPOSE/AIM OF THE STUDY

Colposcopy-directed cervical biopsy has played a major role in diagnosing cervical lesions. The precision of colposcopy-guided biopsy has been questioned. We analyzed several factors that may be correlated with the accuracy of biopsy.

METHODS

PubMed, EMBASE were searched from January 1, 1998 to March 1, 2020. Odds ratio with 95% confidence intervals (CIs) were calculated.

SELECTION CRITERIA

Included studies evaluated factors correlated with the accuracy of biopsy and patients' final diagnosis was established by histological examination of the specimen obtained by conization, loop electrosurgical excision procedure (LEEP), or colpohysterectomy.

RESULTS

A total of 10 studies were selected for the systematic review and meta-analysis. The pooled analysis indicated that the diagnostic inaccuracies of colposcopy-directed cervical biopsy were magnified in women who were 50 years of age or older. Postmenopausal status and transformation zone 3 type were also associated with the diagnostic inaccuracies of colposcopy-directed biopsy. High-grade squamous intraepithelial lesions had better concordance rates than low-grade squamous intraepithelial lesions. The number of vaginal deliveries, number of biopsies, and HPV type were associated with biopsy underdiagnosis and biopsy overestimation.

CONCLUSIONS

This meta-analysis found that the correlation between the histological findings at biopsy and after surgical treatment was influenced by women's age, menopausal status, and the transformation zone type. The diagnostic efficacy was also better for high-grade squamous intraepithelial lesions than for low-grade squamous intraepithelial lesions. Further large-scale randomized clinical trials are required to analyze the factors correlated with biopsy underdiagnosis and biopsy overestimation.

Evaluation of the accuracy of colposcopy in detecting high-grade squamous intraepithelial lesion and cervical cancer

PURPOSE

The primary aim of this study was to evaluate the diagnostic accuracy of colposcopy in identifying high-grade squamous intraepithelial lesion or worse (HSIL+) and the characteristic performance of colposcopic images with various severity levels of cervical lesions.

METHODS

The medical records from 1828 women who underwent colposcopy at Affiliated Hospital of Tongji University from February 2016 to March 2019 were reviewed. Human papilloma virus (HPV) GenoArray test kit (HybriBio Ltd) and Thinprep cytologic test (TCT, Hologic, USA) were used to perform HPV genotyping and cytology. All colposcopic images were collected from the standard-of-care colposcope (Leisegang 3ML LED) and evaluated based on the 2011 International Federation of Cervical Pathology and Colposcopy (IFCPC) Colposcopy Standards. The linear by linear association, Pearson χ² test, χ² test, Kappa test, McNemar test and risk test were used to perform statistical analyses.

RESULTS

The consistency between colposcopy and biopsy pathology was 59.35% with the moderate strength of kappa coefficient of 0.464. The sensitivity, specificity, positive predictive value (PPV) and negative predictive value (NPV) of colposcopy and cytology for HSIL+ were 56.29%, 93.82%, 77.47%, 85.04% and 37.13%, 98.49%, 90.29%, 80.58%, respectively. The colposcopic features of HSIL+ were as follows: (1) thick or bulgy acetowhite epithelium with sharp border; (2) completely nonstained of Lugol's iodine; (3) type III/IV/V of gland openings; (4) punctation or atypical vessels.

CONCLUSION

The data and findings herein provide the resource for evaluating the diagnostic value of colposcopy, and suggested that the accuracy of colposcopy is required to be further improved.

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.

High resolution multispectral endoscopy significantly improves the diagnostic accuracy of cervical intraepithelial lesions

Colposcopy is a visual technique to examine the cervix and determine selection of sites for biopsies and eligibility for treatment. It's always been a critical part of identifying preinvasive and early invasive cervical carcinoma. Unfortunately, challenges exist with regards to the accuracy of traditional colposcopy. Hence, to fully exploit the benefit of increasing diagnostic sensitivity, there is a pressing need to improve the performance of colposcopy by applying novel innovations and techniques. In this case report, we used a recently developed, high-resolution multispectral endoscopy and evaluated its performance by comparing colposcopic image features (the vascular pattern, in particular, depending upon the improved optics and illumination) with histology results. High-resolution multispectral endoscopy makes it easier to distinguish the features of pathological vessels, so that it has a higher sensitivity and specificity to detect cervical lesions, especially in discriminating the vascular pattern using multispectral technology.

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.

Performance of DNA methylation assays for detection of high-grade cervical intraepithelial neoplasia (CIN2+): a systematic review and meta-analysis

Background

To conduct a meta-analysis of performance of DNA methylation in women with high-grade cervical intraepithelial neoplasia (CIN2+).

Methods

Medline and Embase databases were searched for studies of methylation markers versus histological endpoints. Pooled sensitivity, specificity and positive predictive value (PPV) for CIN2+ were derived from bivariate models. Relative sensitivity and specificity for CIN2+ compared to cytology and HPV16/18 genotyping were pooled using random-effects models.

Results

Sixteen thousand three hundred thirty-six women in 43 studies provided data on human genes (CADM1, MAL, MIR-124-2, FAM19A4, POU4F3, EPB41L3, PAX1, SOX1) and HPV16 (L1/L2). Most (81%) studies evaluated methylation assays following a high-risk (HR)-HPV-positive or abnormal cytology result. Pooled CIN2+ and CIN3+ prevalence was 36.7% and 21.5%. For a set specificity of 70%, methylation sensitivity for CIN2+ and CIN3+ were 68.6% (95% CI: 62.9–73.8) and 71.1% (95% CI: 65.7–76.0) and PPV were 53.4% (95% CI: 44.4–62.1) and 35.0% (95% CI: 28.9–41.6). Among HR-HPV+ women, the relative sensitivity of methylation for CIN2+ was 0.81 (95% CI: 0.63–1.04) and 1.22 (95% CI: 1.05–1.42) compared to cytology of atypical squamous cells of undetermined significance, or greater (ASCUS+) and HPV16/18 genotyping, respectively, while relative specificity was 1.25 (95% CI: 0.99–1.59) and 1.03 (95% CI: 0.94–1.13), respectively.

Conclusion

DNA methylation is significantly higher in CIN2+ and CIN3+ compared to ≤CIN1. As triage test, DNA methylation has higher specificity than cytology ASCUS+ and higher sensitivity than HPV16/18 genotyping.

Combined dynamic spectral imaging and routine colposcopy strategy for the diagnosis of pre-cancerous cervical lesions

The present study aimed to investigate the sensitivity and specificity of combined dynamic spectral imaging (DySI) and routine colposcopy in diagnosing pre-cancerous lesions in subjects with abnormal cytological results. The retrospective study included 146 patients diagnosed with cervical lesions and atypical squamous cells of undetermined significance according to a colposcopy examination. Data from colposcopy clinics were used to evaluate performance of DySI in different histological types. The present study evaluated the clinical performance of two different referral strategies (single diagnosis or combined diagnosis) in combination with a smear test. The sensitivity of DySI and routine colposcopy for detecting severe pre-cancerous cervical disease in patients referred with a borderline histology or mild dyskaryosis was 69% [95% confidence interval (CI): 56-82%] and 43% (95% CI: 28-57%), respectively (P=0.01). However, for the HSIL group, the sensitivity of DySI and routine colposcopy was 64 and 61%, respectively. In the HSIL group, the sensitivity was as high as 85% when the DySI method was combined with routine colposcopy. When the conditions of new screening strategies were applied to remove those patients with a negligible risk, DySI had a higher sensitivity to detect severe pre-cancerous cervical disease than conventional colposcopy. In conclusion, the combined DySI and routine colposcopy strategy had a higher diagnostic sensitivity in subjects with low or high abnormalities on cytological examination, compared with either method separately. The present study suggests that the baseline colposcopy sensitivity may be enhanced with the adjunctive use of DySI, irrespective of the cytology result for referral.

The diagnostic accuracy of colposcopy - A review of research methodology and impact on the outcomes of quality assurance

OBJECTIVE

To review the published diagnostic accuracy figures for the performance of colposcopy and to assess how the various forms of bias might explain the very wide range of reported values and the impact they have on quality assurance of cervical screening.

METHODS

Publications were only selected where they contained sufficient raw data to enable diagnostic accuracy statistics to be calculated for the detection of cervical intraepithelial neoplasia grade 2+ (CIN2+), as determined by punch biopsy. In addition, both the colposcopic impression at the time of examination and the disease threshold used to determine the need for biopsy must have been reported.

RESULTS

Large differences in diagnostic accuracy figures were found when the output of colposcopy was defined either, on the basis that the colposcopist thought there was CIN2+ present or, that the colposcopist considered there to be some disease present and so took a biopsy to confirm this. Weighted mean sensitivity was 68.5% (95% CI 59.9-77.1) for the first method but 95.7% (95% CI 93.4-98.0) for the second method. Weighted mean specificity was 75.9% (95% CI 69.3-82.5) for the first method but 34.2% (95% CI 27.0-41.4) for the second method. Weighted mean PPV was 68.9% (95% CI 64.2-73.6) for the first method but 54.3% (95% CI 46.5-62.1) for the second method.

CONCLUSION

The main reason for the wide range of published diagnostic accuracy figures, arises from the use of two different methods of assessing the output of colposcopy. Colposcopic Impression is appropriate when assessing the performance of a colposcopist at the time of examination, but the taking of a biopsy to confirm that Disease is Present should be used when assessing patient management. Accurate assessment of both outcomes is fundamental to any quality assurance programme.

Adjunctive colposcopy technologies for assessing suspected cervical abnormalities: systematic reviews and economic evaluation

BACKGROUND

Dynamic Spectral Imaging System (DySIS)map (DySIS Medical Ltd, Edinburgh, UK) and ZedScan (Zilico Limited, Manchester, UK) can be used adjunctively with conventional colposcopy, which may improve the detection of cervical intraepithelial neoplasia (CIN) and cancer.

OBJECTIVES

To systematically review the evidence on the diagnostic accuracy, clinical effectiveness and implementation of DySISmap and ZedScan as adjuncts to standard colposcopy, and to develop a cost-effectiveness model.

METHODS

Four parallel systematic reviews were performed on diagnostic accuracy, clinical effectiveness issues, implementation and economic analyses. In January 2017 we searched databases (including MEDLINE and EMBASE) for studies in which DySISmap or ZedScan was used adjunctively with standard colposcopy to detect CIN or cancer in women referred to colposcopy. Risk of bias was assessed with the Quality Assessment of Diagnostic Accuracy Studies (QUADAS)-2 tool. Summary estimates of diagnostic accuracy were calculated using bivariate and other regression models when appropriate. Other outcomes were synthesised narratively. A patient-level state-transition model was developed to evaluate the cost-effectiveness of DySISmap and ZedScan under either human papillomavirus (HPV) triage or the HPV primary screening algorithm. The model included two types of clinics ['see and treat' and 'watchful waiting' (i.e. treat later after confirmatory biopsy)], as well as the reason for referral (low-grade or high-grade cytological smear). Sensitivity and scenario analyses were undertaken.

RESULTS

Eleven studies were included in the diagnostic review (nine of DySISmap and two of ZedScan), three were included in the clinical effectiveness review (two of DySISmap and one of ZedScan) and five were included in the implementation review (four of DySISmap and one of ZedScan). Adjunctive DySISmap use was found to have a higher sensitivity for detecting CIN grade 2+ (CIN 2+) lesions [81.25%, 95% confidence interval (CI) 72.2% to 87.9%] than standard colposcopy alone (57.91%, 95% CI 47.2% to 67.9%), but with a lower specificity (70.40%, 95% CI 59.4% to 79.5%) than colposcopy (87.41%, 95% CI 81.7% to 91.5%). (Confidential information has been removed.) The base-case cost-effectiveness results showed that adjunctive DySISmap routinely dominated standard colposcopy (it was less costly and more effective). The only exception was for high-grade referrals in a watchful-waiting clinic setting. The incremental cost-effectiveness ratio for ZedScan varied between £272 and £4922 per quality-adjusted life-year. ZedScan also dominated colposcopy alone for high-grade referrals in see-and-treat clinics. These findings appeared to be robust to a wide range of sensitivity and scenario analyses.

LIMITATIONS

All but one study was rated as being at a high risk of bias. There was no evidence directly comparing ZedScan with standard colposcopy. No studies directly compared DySIS and ZedScan.

CONCLUSIONS

The use of adjunctive DySIS increases the sensitivity for detecting CIN 2+, so it increases the number of high-grade CIN cases that are detected. However, it also reduces specificity, so that more women with no or low-grade CIN will be incorrectly judged as possibly having high-grade CIN. The evidence for ZedScan was limited, but it appears to increase sensitivity and decrease specificity compared with colposcopy alone. The cost-effectiveness of both adjunctive technologies compared with standard colposcopy, under both the HPV triage and primary screening algorithms, appears to be favourable when compared with the conventional thresholds used to determine value in the NHS.

FUTURE WORK

More diagnostic accuracy studies of ZedScan are needed, as are studies assessing the diagnostic accuracy for women referred to colposcopy as part of the HPV primary screening programme.

STUDY REGISTRATION

This study is registered as PROSPERO CRD42017054515.

FUNDING

The National Institute for Health Research Health Technology Assessment programme.

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

In a study of “real-world” practice, digital colposcopy with dynamic spectral imaging mapping increased the detection of women with high-grade CIN compared with standard colposcopy.

Objective

The aim of the study was to determine, in a wide “real-world” setting, whether digital colposcopy with adjunctive dynamic spectral imaging (DSI) mapping increases the detection of women with high-grade cervical intraepithelial neoplasia (CIN).

Materials and Methods

A multicenter, two-arm, observational, cross-sectional study that recruited women 21 years and older, having colposcopy after a low-grade abnormality screening result. The prospective arm collected outcomes of digital colposcopy with DSI used for identifying biopsy sites at the colposcopists' discretion. The retrospective control arm (number of subjects matched 1:1 per colposcopist) collected outcomes of standard colposcopy. The primary outcome was histopathological detection of women with CIN 2+ by colposcopic biopsy.

Results

The study included 1,788 women in the retrospective and 1,857 in the prospective arm from 39 US community-based clinics. Subject characteristics were comparable. A total of 71.6% of the women in the retrospective and 71.5% in the prospective arm underwent biopsy. The average number of biopsies increased from 1.032 (retrospective) to 1.256 (prospective). The yield of CIN 2+ patients was 7.21% in the retrospective and 9.48% in the prospective arm, a 2.27% difference (95% confidence interval = 0.47%–4.07%, p = .014) and 31.4% relative increase. The yield of CIN 3+ patients was 2.07% in the retrospective and 3.23% in the prospective arm, a 1.16% (95% confidence interval = 0.12%–2.24%, p = .031) absolute difference and 56.1% relative increase. The false-positive rates for biopsied patients were comparable (64.43% vs 62.04%, p = .139).

Conclusions

Digital colposcopy with the adjunctive DSI increased CIN 2+ and CIN 3+ detection in low-grade referrals compared with standard colposcopy, with a similar number of women undergoing biopsy.

Detecting tumour-positive resection margins after oral cancer surgery by spraying a fluorescent tracer activated by gamma-glutamyltranspeptidase

OBJECTIVES

Tumour-positive resection margins are a major problem during oral cancer surgery. gGlu-HMRG is a tracer that becomes fluorescent upon activation by gamma-glutamyltranspeptidase (GGT). This study aims to investigate the combination of gGlu-HMRG and a clinical fluorescence imaging system for the detection of tumour-positive resection margins.

MATERIALS AND METHODS

The preclinical Maestro and clinical Artemis imaging systems were compared in vitro and ex vivo with cultured human head and neck cancer cells (OSC19, GGT-positive; and FaDu, GGT negative) and tumour-bearing nude mice. Subsequently, frozen sections of normal and oral cancer tissues were ex vivo sprayed with gGlu-HMRG to determine the sensitivity and specificity. Finally, resection margins of patients with suspected oral cancer were ex vivo sprayed with gGlu-HMRG to detect tumour-positive resection margins.

RESULTS

Both systems could be used to detect gGlu-HMRG activation in vitro and ex vivo in GGT positive cancer cells. Sensitivity and specificity of gGlu-HMRG and the Artemis on frozen tissue samples was 80% and 87%, respectively. Seven patients undergoing surgery for suspected oral cancer were included. In three patients fluorescence was observed at the resection margin. Those margins were either tumour-positive or within 1 mm of tumour. The margins of the other patients were clear (≥8 mm).

CONCLUSION

This study demonstrates the feasibility to detect tumour-positive resection margins with gGlu-HMRG and a clinical fluorescence imaging system. Applying this technique would enable intraoperative screening of the entire resection margin and allow direct re-resection in case of tumour-positivity.

Diagnostic accuracy of colposcopy with dynamic spectral imaging for cytology-negative/high-risk HPV positive (failed test of cure) after large loop excision of the transformation zone (LLETZ) of the cervix: Results of the DySIS colposcopy 1 study

After treatment for cervical intraepithelial neoplasia (CIN), in the UK women who are cytology-negative, high-risk (HR) human papilloma virus (HPV) positive are referred to colposcopy. This pilot study assessed the incidence of residual/recurrent CIN and the diagnostic accuracy of colposcopy with dynamic spectral imaging (DSI) mapping in their detection.This was a prospective service evaluation carried out in a UK National Health Service (NHS) colposcopy clinic. All women, referred with negative cytology/HR-HPV positive result following treatment for CIN from March 2013 until November 2014, who were examined with the DSI digital colposcope were included. We excluded 3 cases because of poor-quality imaging from user errors. Everyday clinical practice was followed. Initial colposcopic impression, DSI map indication, and biopsy site selections were recorded. CIN2+ was considered the primary outcome and CIN of any grade a secondary outcome.A total of 105 women were included of which 5 (4.8%) had CIN2+ histology and 24 (22.9%) had CIN1. Pre-DSI map colposcopy suggested normal/low grade in all 5 of the CIN2+ cases and DSI suggested high-grade (HG) CIN in 4 of the 5 cases. Sensitivity of standard colposcopy for CIN2+ was 0%, improving to 80% with the incorporation of the DSI map.The CIN burden in this population is higher than previously expected. Colposcopic identification of HG CIN appears to improve significantly with DSI in this cohort leading to refinement in patient management. A larger, multicentric prospective study (DySIS colposcopy 2) is planned to confirm these initial findings.

Standardized Digital Colposcopy with Dynamic Spectral Imaging for Conservative Patient Management

Background

Colposcopy is subjective and management of young patients with high-grade disease is challenging, as treatments may impair subsequent pregnancies and adversely affect obstetric outcomes. Conservative management of selected patients is becoming more popular amongst clinicians; however it requires accurate assessment and documentation. Novel adjunctive technologies for colposcopy could improve patient care and help individualize management decisions by introducing standardization, increasing sensitivity, and improving documentation.

Case

A nulliparous 27-year-old woman planning pregnancy underwent colposcopy following high-grade cytology. The colposcopic impression was of low-grade changes, whilst the Dynamic Spectral Imaging (DSI) map of the cervix suggested potential high-grade. A DSI-directed biopsy confirmed CIN2. At follow-up, both colposcopy and DSI were suggestive of low-grade disease only, and image comparison confirmed the absence of previously present acetowhite epithelium areas. Histology of the transformation zone following excisional treatment, as per patient's choice, showed no high-grade changes.

Conclusion

Digital colposcopy with DSI mapping helps standardize colposcopic examinations, increase diagnostic accuracy, and monitor cervical changes over time, improving patient care. When used for longitudinal tracking of disease and when it confirms a negative colposcopy, it can help towards avoiding overtreatment and hence decrease morbidity related to cervical excision.

Efficacy of thermoablation in treating cervical precancerous lesions in a low-resource setting

Introduction

Treating cervical intraepithelial neoplasia (CIN) grades 2 and 3 is the recommended strategy for preventing invasive carcinoma in low- and middle-income countries (LMICs). Our objective was to assess the efficacy of thermoablation in the treatment of CIN2 and CIN3 in a screen-and-treat approach.

Methods

Women aged 30-49 years in Dschang, Cameroon, were invited to undergo vaginal sampling for human papillomavirus (HPV), samples being assessed by an Xpert HPV Assay. HPV-positive women underwent visual inspection with acetic acid (VIA) and visual inspection with Lugol's iodine (VILI), cervical biopsy, and endocervical curettage. Women positive for HPV-16/18/45 or other HPV types with abnormal VIA/VILI were treated by thermoablation on the same day. The primary outcome was persistence of high-grade disease on cytologic examination at 12 months.

Results

Of a total of 1,012 recruited women, 188 were HPV-positive, 121 patients required thermoablation, and 99 had a CIN of grade <2, making the overtreatment rate 9.9%. The cure rate for CIN2 and CIN3 at 12 months was 70.6%. Failure (higher risk of persistent disease) was associated with the presence of occult endocervical lesions at baseline diagnosis (adjusted odds ratio [aOR] =128.97 [95% confidence interval [CI], 8.80-1,890.95]; p<0.0001). First sexual intercourse before the age of 15 was also a risk factor (aOR =0.003 [95% CI, 0.001-0.61]; p=0.023).

Conclusion

In LMICs, use of thermoablation in a screen-and-treat approach is a valuable treatment option for CIN2 and CIN3. Studies comparing thermoablation with cryotherapy are needed to determine the most appropriate treatment for cervical precancer in such countries.

Comparison between performance of single-fiber reflectance spectroscopy (SFRS) system and colposcopy: a phase III trial

Herein, the performance of single-fiber reflectance spectroscopy (SFRS) in detection of cervical pre-cancerous squamous intraepithelial lesions (SIL) was compared with colposcopy. Based on the previous results obtained from 167 samples and finding the contributing parameters in differentiating SILs from non-SILs, a user-friendly interface was developed to detect the SILs using SFRS system. Detection of SILs in 301 patients was performed by both SFRS system and routine colposcopy. In addition to physician-determined sites, four quarters of the cervix were measured by SFRS system and suspicious lesions detected by either method were biopsied. Histopathologic results of the biopsied species were compared to the physician judgments based on colposcopy and the results of SFRS system. SFRS could differentiate between SILs and non-SILs with mean sensitivity, specificity, positive predictive value (PPV), and negative predictive value (NPV) of 38.3, 60.9, 15.2, and 84.3%, respectively. These values were obtained as 88.3, 10.6, 15.4, and 83.1% for the colposcopy, respectively. Although sensitivity of SFRS in detection of SILs is about twofold less than the colposcopy, it can reduce the number of unnecessary biopsies by a factor of more than 5.5. Therefore, the aid of SFRS system to the physician can reduce the number of unnecessary biopsies. On the other hand, both colposcopy and SFRS methods equally suffer from low detection worth in terms of positive/negative predictive values. In conclusion, using the online, simple and non-invasive SFRS system to choose between several suspicious sites in a patient in the clinic may be recommended.

Increased detection of precancerous cervical lesions with adjunctive dynamic spectral imaging

Objective

To validate, in US community-based colposcopy clinics, previous reports of increased detection of high-grade cervical intraepithelial neoplasia (CIN2+) with biopsies selected using dynamic spectral imaging (DSI) mapping after standard colposcopy.

Study design

Cross-sectional observational study of 26 colposcopists across nine clinics recruiting consecutive colposcopy patients. Standard assessment with biopsy selections was completed before seeing the DSI map which was subsequently interpreted and used for additional biopsies per clinical judgment. Primary measure was the number of women with CIN2+ detected by DSI-assisted biopsies, over those detected by standard colposcopy biopsies.

Results

A total of 887 women were recruited. After exclusions, 881 women and 1,189 biopsies were analyzed. Standard biopsy detected 78 women with CIN2+ and DSI-assisted biopsies another 34, increasing the detection rate from 8.85% to 12.71% (p=0.00016). This was achieved with 16.16% of DSI-assisted biopsies finding CIN2+ compared to 13.24% for the preceding standard biopsies. For secondary specificity analysis, 431 women had only <CIN2 in standard biopsy/ies, a 48.92% rate, while 131 women who underwent no standard biopsy/ies had DSI-assisted biopsy/ies which were all <CIN2, a 35.22% rate (p<0.0001).

Conclusion

The largest study, to date, of DSI used in colposcopy confirms previously reported increased detection of CIN2+, across multiple US community-based clinics. Based on the improved efficiency of the DSI-assisted biopsies, this increase suggests an improved diagnostic capacity achieved with DSI and cannot be explained solely by the taking of additional biopsies.

Optimization of Classification Strategies of Acetowhite Temporal Patterns towards Improving Diagnostic Performance of Colposcopy

Efforts have been being made to improve the diagnostic performance of colposcopy, trying to help better diagnose cervical cancer, particularly in developing countries. However, improvements in a number of areas are still necessary, such as the time it takes to process the full digital image of the cervix, the performance of the computing systems used to identify different kinds of tissues, and biopsy sampling. In this paper, we explore three different, well-known automatic classification methods (k-Nearest Neighbors, Naïve Bayes, and C4.5), in addition to different data models that take full advantage of this information and improve the diagnostic performance of colposcopy based on acetowhite temporal patterns. Based on the ROC and PRC area scores, the k-Nearest Neighbors and discrete PLA representation performed better than other methods. The values of sensitivity, specificity, and accuracy reached using this method were 60% (95% CI 50–70), 79% (95% CI 71–86), and 70% (95% CI 60–80), respectively. The acetowhitening phenomenon is not exclusive to high-grade lesions, and we have found acetowhite temporal patterns of epithelial changes that are not precancerous lesions but that are similar to positive ones. These findings need to be considered when developing more robust computing systems in the future.

Alternative Colposcopy Techniques: A Systematic Review and Meta-analysis

OBJECTIVE

To assess the diagnostic value of alternative (digital) colposcopy techniques for detection of cervical intraepithelial neoplasia (CIN) 2 or worse in a colposcopy population.

DATA SOURCES

MEDLINE, EMBASE, ClinicalTrials.gov, and the Cochrane Library were searched from inception up to January 11, 2016, for studies that evaluated the diagnostic value of alternative (digital) colposcopy techniques.

METHODS OF STUDY SELECTION

Inclusion criteria were: 1) an alternative (digital) colposcopy technique was used in a colposcopy population; 2) a histologic outcome was reported, classified as CIN, differentiating between mild dysplasia or less (CIN 1 or less), and moderate dysplasia or worse (CIN 2 or greater); 3) the entire cervix was scanned at once or a per-woman analysis was performed; 4) no other topical application than acetic acid and Lugol's solution was used; 5) at least three eligible studies had to be available within a single technique; and 6) studies obtained research ethics approval. Language was restricted to English.

TABULATION, INTEGRATION, AND RESULTS

Two reviewers assessed the eligibility of the identified articles. Disagreements were resolved by a third reviewer. Thirteen studies met the inclusion criteria. We found six studies on fluorescence and reflectance spectroscopy, including 2,530 women, with a pooled sensitivity of 93% (95% confidence interval [CI] 89-95%) and specificity of 62% (95% CI 47-76%). Four studies on dynamic spectral imaging were found including 1,173 women with a pooled sensitivity of 69% (95% CI 48-85%) and specificity of 83% (95% CI 76-88%). We found three studies on optical coherence tomography including 693 women with a pooled sensitivity of 48% (95% CI 32-64%) and specificity of 77% (95% CI 52-91%). Previously published conventional colposcopy results showed a sensitivity of 61% (95% CI 58-63%) and a specificity of 85% (95% CI 83-86%).

CONCLUSION

Alternative (digital) colposcopy techniques may result in increased sensitivity and specificity, but no recommendation for introduction in clinical practice can be made yet.

The impact of human papillomavirus type on colposcopy performance in women offered HPV immunisation in a catch-up vaccine programme: a two-centre observational study

OBJECTIVE

To determine whether human papillomavirus (HPV) immunisation has affected the prevalence of HPV genotypes and colposcopic features of cervical intraepithelial neoplasia (CIN) in young women referred for colposcopy.

DESIGN

A two-centre observational study including vaccinated and unvaccinated women.

SETTING

Colposcopy clinics serving two health regions in Scotland, UK.

POPULATION

A total of 361 women aged 20-25 years attending colposcopy following an abnormal cervical cytology result at routine cervical screening.

METHODS

Cervical samples were obtained from women for HPV DNA genotyping and mRNA E6/E7 expression of HPV 16, 18, 31, 33, and 45. Demographic data, cytology, and histology results and colposcopic features were recorded. Chi-square analysis was conducted to identify associations between vaccine status, HPV genotypes, and colposcopic features.

MAIN OUTCOME MEASURES

Colposcopic features, HPV genotypes, mRNA expression, and cervical histology.

RESULTS

The prevalence of HPV 16 was significantly lower in the vaccinated group (8.6%) compared with the unvaccinated group (46.7%) (P = 0.001). The number of cases of CIN2+ was significantly lower in women who had been vaccinated (P = 0.006). The HPV vaccine did not have a statistically significant effect on commonly recognised colposcopic features, but there was a slight reduction in the positive predictive value (PPV) of colposcopy for CIN2+, from 74% (unvaccinated) to 66.7% (vaccinated).

CONCLUSIONS

In this group of young women with abnormal cytology referred to colposcopy, HPV vaccination via a catch-up programme reduced the prevalence of CIN2+ and HPV 16 infection. The reduced PPV of colposcopy for the detection of CIN2+ in women who have been vaccinated is at the lower acceptable level of the UK national cervical screening programme guidelines.

TWEETABLE ABSTRACT

Reduction of hrHPV positivity and CIN in immunised women consistent with lower PPV of colposcopy for CIN2+.

How Colposcopy Misses Invasive Cervical Cancer: A Case Report from the IMPROVE-COLPO Study

Colposcopy with biopsy is pivotal to cervical cancer prevention programs as it is called to identify the precancerous lesions on patients that screen positive. We present a cervical cancer case from IMPROVE-COLPO, a postmarketing, multicenter, two-arm observational study on US community colposcopy that collects outcomes with the adjunctive Dynamic Spectral Imaging (DSI) in its prospective arm. A 45-year-old woman was seen for suffering of heavy periods. She had cytology of Atypical Squamous Cells of Undetermined Significance (ASC-US) and was Human Papillomavirus (HPV) positive. Her colposcopy did not recognize the underlying condition and opted for no biopsy. The DSI assessment led to a biopsy of a lesion challenging traditional colposcopic templates: small, away from the cervical os, with slow acetowhitening development. Pathology review revealed the presence of invasive squamous carcinoma. In the era of sensitive screening, it is concerning that invasive cancers can challenge colposcopy and that the way to improve colposcopy is to collect multiple biopsies from each patient. The case presented indicates that the adjunctive objective assessment by DSI increases reassurance that observations outside of traditional standard visual templates are not underestimated or ignored.

Novel advancements in colposcopy: historical perspectives and a systematic review of future developments

OBJECTIVE

To describe novel innovations and techniques for the detection of high-grade dysplasia.

MATERIALS AND METHODS

Studies were identified through the PubMed database, spanning the last 10 years. The key words (["computerized colposcopy" or "digital colposcopy" or "spectroscopy" or "multispectral digital colposcopy" or "dynamic spectral imaging", or "electrical impedance spectroscopy" or "confocal endomicroscopy" or "confocal microscopy"or "optical coherence tomography"] and ["cervical dysplasia" or cervical precancer" or "cervix" or "cervical"]) were used. The inclusion criteria were published articles of original research referring to noncolposcopic evaluation of the cervix for the detection of cervical dysplasia. Only English-language articles from the past 10 years were included, in which the technologies were used in vivo, and sensitivities and specificities could be calculated.

RESULTS

The single author reviewed the articles for inclusion. Primary search of the database yielded 59 articles, and secondary cross-reference yielded 12 articles. Thirty-two articles met the inclusion criteria.

CONCLUSIONS

An instrument that globally assesses the cervix, such as computer-assisted colposcopy, optical spectroscopy, and dynamic spectral imaging, would provided the most comprehensive estimate of disease and is therefore best suited when treatment is preferred. Electrical impedance spectroscopy, confocal microscopy, and optical coherence tomography provide information at the cellular level to estimate histology and are therefore best suited when deferment of treatment is preferred. If a device is to eventually replace the colposcope, it will likely combine technologies to best meet the needs of the target population, and as such, no single instrument may prove to be universally appropriate. Analyses of false-positive rates, additional colposcopies and biopsies, cost, and absolute life-savings will be important when considering these technologies and are limited thus far.

Women's Preferences of Dynamic Spectral Imaging Colposcopy

BACKGROUND

The focus of testing the dynamic spectral imaging (DSI) colposcope has been on the technical characteristics and clinical performance. However, aspects from a patient's perspective are just as important.

METHODS

This study was designed as a substudy of the DSI validation study, a prospective comparative, multicenter clinical trial to assess the clinical performance of DSI colposcopy. All women included in this study were asked to complete two questionnaires: a patient characteristics questionnaire and a patient satisfaction questionnaire.

RESULTS

In the initial study a total of 239 women were included in the intention-to-treat cohort. Of these, 230 women (96.2%) completed both questionnaires. When assessing the women's preferences for some of the possible uses of DSI colposcopy, a high level of agreement was noted for all potential implementations. In general, women found the additional time DSI colposcopy took acceptable: just 15 women (6.5%) thought the time DSI colposcopy took made them feel uncomfortable. Furthermore, women ranked test accuracy as the most important characteristic, followed by (more) rapid testing and comfort. Quick notification of the results and costs were considered the least important characteristics.

CONCLUSION

Women are willing to accept discomfort in the form of an additional or longer test if there is clinical benefit.

Advances in colposcopy: new technologies to challenge current practice

Colposcopy has a poor sensitivity to detect precancerous abnormalities of the cervix. These abnormalities will become less common after HPV vaccinated girls enter the screened population. However HPV-based screening is likely to result in more colposcopic referrals. Both these changes to cervical screening programs will reduce the incidence of high grade CIN and cervical cancer as well as the prevalence of high grade CIN presenting to the colposcopist. As a consequence the diagnostic performance of conventional colposcopy will be further challenged. This review aims to discuss leading technologies which are currently available as an alternative or in addition to colposcopy and may serve to improve the current colposcopic assessment of precancerous cervical abnormalities.

Impact of HPV immunization on the detection of cervical disease

Human papillomavirus (HPV) is the primary cause of cervical cancer and genital warts. The development of HPV vaccines has been a major advance in the prevention of these diseases. Recent studies have shown promising early effects of HPV immunization programs on cervical abnormalities and genital warts, with evidence of herd immunity against genital warts also emerging in Australia. Further studies are required to not only continue monitoring the effect of the HPV immunization on the incidence of these diseases, but also to establish the effect the immunization will have on cervical screening programs and the performance of colposcopy.

Early detection of high-grade squamous intraepithelial lesions in the cervix with quantitative spectroscopic imaging

Quantitative spectroscopy has recently been extended from a contact-probe to wide-area spectroscopic imaging to enable mapping of optical properties across a wide area of tissue. We train quantitative spectroscopic imaging (QSI) to identify cervical high-grade squamous intraepithelial lesions (HSILs) in 34 subjects undergoing the loop electrosurgical excision procedure (LEEP subjects). QSI's performance is then prospectively evaluated on the clinically suspicious biopsy sites from 47 subjects undergoing colposcopic-directed biopsy. The results show the per-subject normalized reduced scattering coefficient at 700 nm (An) and the total hemoglobin concentration are significantly different (p<0.05) between HSIL and non-HSIL sites in LEEP subjects. An alone retrospectively distinguishes HSIL from non-HSIL with 89% sensitivity and 83% specificity. It alone applied prospectively on the biopsy sites distinguishes HSIL from non-HSIL with 81% sensitivity and 78% specificity. The findings of this study agree with those of an earlier contact-probe study, validating the robustness of QSI, and specifically An, for identifying HSIL. The performance of An suggests an easy to use and an inexpensive to manufacture monochromatic instrument is capable of early cervical cancer detection, which could be used as a screening and diagnostic tool for detecting cervical cancer in low resource countries.

The use of optical spectroscopy for in vivo detection of cervical pre-cancer

In order to investigate the effectiveness of optical spectroscopy for in vivo diagnosis of cervical pre-cancerous conditions, a series of published studies are surveyed. The six optical technologies investigated include fluorescence spectroscopy, reflectance spectroscopy, and their combination using point probe or multispectral imaging approaches. Searching in the well-known databases, the most recent published works were sought out. Various aspects of the studies were evaluated including the details of the technology used, the pathologic threshold for tissue classification and the gold standard, the study population and prevalence of disease in this population, the method of measurement, the number of clinicians involved in the study, the classification and validation algorithms, and the performance in terms of sensitivity, specificity and, when available, the area under the receiver operating characteristic curve. Forty-four studies conducted from 1994 to 2012 were evaluated. The data are gathered in two comprehensive tables, and five illustrations are provided to simplify a comparison between studies from different points of view. There is a broad band of studies from small pilot studies through phase III clinical trials. Among the reviewed articles, only three factors were found to influence the performance of the optical spectroscopy studies. Multispectral approaches show higher specificity than the point probe approaches (p = 0.001). The use of acetic acid before measurement and prevalence of disease among the studied population, also, have an impact on the sensitivity and specificity of the studies (p < 0.05), respectively.

Adjunctive colposcopy technologies for examination of the uterine cervix--DySIS, LuViva Advanced Cervical Scan and Niris Imaging System: a systematic review and economic evaluation

BACKGROUND

Women in England (aged 25-64 years) are invited for cervical screening every 3-5 years to assess for cervical intraepithelial neoplasia (CIN) or cancer. CIN is a term describing abnormal changes in the cells of the cervix, ranging from CIN1 to CIN3, which is precancerous. Colposcopy is used to visualise the cervix. Three adjunctive colposcopy technologies for examination of the cervix have been included in this assessment: Dynamic Spectral Imaging System (DySIS), the LuViva Advanced Cervical Scan and the Niris Imaging System.

OBJECTIVE

To determine the clinical effectiveness and cost-effectiveness of adjunctive colposcopy technologies for examination of the uterine cervix for patients referred for colposcopy through the NHS Cervical Screening Programme.

DATA SOURCES

Sixteen electronic databases [Allied and Complementary Medicine Database (AMED), BIOSIS Previews, Cochrane Database of Systematic Reviews (CDSR), Cochrane Central Register of Controlled Trials (CENTRAL), Cumulative Index to Nursing and Allied Health Literature (CINAHL), Database of Abstracts of Reviews of Effects (DARE), EMBASE, Health Management Information Consortium (HMIC), Health Technology Assessment (HTA) database; Inspec, Inside Conferences, MEDLINE, NHS Economic Evaluation Database (NHS EED), PASCAL, Science Citation Index Expanded (SCIE) and Science Citation Index (SCI) - Conference Proceedings], and two clinical trial registries [ClinicalTrials.gov and Current Controlled Trials (CCT)] were searched to September-October 2011.

REVIEW METHODS

Studies comparing DySIS, LuViva or Niris with conventional colposcopy were sought; a narrative synthesis was undertaken. A decision-analytic model was developed, which measured outcomes in terms of quality-adjusted life-years (QALYs) and costs were evaluated from the perspective of the NHS and Personal Social Services with a time horizon of 50 years.

RESULTS

Six studies were included: two studies of DySIS, one study of LuViva and three studies of Niris. The DySIS studies were well reported and had a low risk of bias; they found higher sensitivity with DySIS (both the DySISmap alone and in combination with colposcopy) than colposcopy alone for identifying CIN2+ disease, although specificity was lower with DySIS. The studies of LuViva and Niris were poorly reported and had limitations, which indicated that their results were subject to a high risk of bias; the results of these studies cannot be considered reliable. The base-case cost-effectiveness analysis suggests that both DySIS treatment options are less costly and more effective than colposcopy alone in the overall weighted population; these results were robust to the ranges tested in the sensitivity analysis. DySISmap alone was more costly and more effective in several of the referral groups but the incremental cost-effectiveness ratio (ICER) was never higher than £1687 per QALY. DySIS plus colposcopy was less costly and more effective in all reasons for referral. Only indicative analyses were carried out on Niris and LuViva and no conclusions could be made on their cost-effectiveness.

LIMITATIONS

The assessment is limited by the available evidence on the new technologies, natural history of the disease area and current treatment patterns.

CONCLUSIONS

DySIS, particularly in combination with colposcopy, has higher sensitivity than colposcopy alone. There is no reliable evidence on the clinical effectiveness of LuViva and Niris. DySIS plus colposcopy appears to be less costly and more effective than both the DySISmap alone and colposcopy alone; these results were robust to the sensitivity analyses undertaken. Given the lack of reliable evidence on LuViva and Niris, no conclusions on their potential cost-effectiveness can be drawn. There is some uncertainty about how generalisable these findings will be to the population of women referred for colposcopy in the future, owing to the introduction of the human papillomavirus (HPV) triage test and uptake of the HPV vaccine.