Multiscale Optical Imaging Fusion for Cervical Precancer Diagnosis: Integrating Widefield Colposcopy and High-Resolution Endomicroscopy.

OBJECTIVE: Early detection and treatment of cervical precancers can prevent disease progression. However, in low-resource communities with a high incidence of cervical cancer, high equipment costs and a shortage of specialists hinder preventative strategies. This manuscript presents a low-cost multiscale in vivo optical imaging system coupled with a computer-aided diagnostic system that could enable accurate, real-time diagnosis of high-grade cervical precancers. METHODS: The system combines portable colposcopy and high-resolution endomicroscopy (HRME) to acquire spatially registered widefield and microscopy videos. A multiscale imaging fusion network (MSFN) was developed to identify cervical intraepithelial neoplasia grade 2 or more severe (CIN 2+). The MSFN automatically identifies and segments the ectocervix and lesions from colposcopy images, extracts nuclear morphology features from HRME videos, and integrates the colposcopy and HRME information. RESULTS: With a threshold value set to achieve sensitivity equal to clinical impression (0.98 [p = 1.0]), the MSFN achieved a significantly higher specificity than clinical impression (0.75 vs. 0.43, p = 0.000006). CONCLUSION: Our findings show that multiscale optical imaging of the cervix allows the highly sensitive and specific detection of high-grade precancers. SIGNIFICANCE: The multiscale imaging system and MSFN could facilitate the accurate, real-time diagnosis of cervical precancers in low-resource settings.

Development of a multimodal mobile colposcope for real-time cervical cancer detection.

Cervical cancer remains a leading cause of cancer death among women in low-and middle-income countries. Globally, cervical cancer prevention programs are hampered by a lack of resources, infrastructure, and personnel. We describe a multimodal mobile colposcope (MMC) designed to diagnose precancerous cervical lesions at the point-of-care without the need for biopsy. The MMC integrates two complementary imaging systems: 1) a commercially available colposcope and 2) a high speed, high-resolution, fiber-optic microendoscope (HRME). Combining these two image modalities allows, for the first time, the ability to locate suspicious cervical lesions using widefield imaging and then to obtain co-registered high-resolution images across an entire lesion. The MMC overcomes limitations of high-resolution imaging alone; widefield imaging can be used to guide the placement of the high-resolution imaging probe at clinically suspicious regions and co-registered, mosaicked high-resolution images effectively increase the field of view of high-resolution imaging. Representative data collected from patients referred for colposcopy at Barretos Cancer Hospital in Brazil, including 22,800 high resolution images and 9,900 colposcope images, illustrate the ability of the MMC to identify abnormal cervical regions, image suspicious areas with subcellular resolution, and distinguish between high-grade and low-grade dysplasia.

Topical Imiquimod for the Treatment of High-Grade Squamous Intraepithelial Lesions of the Cervix: A Randomized Controlled Trial.

OBJECTIVE: To evaluate the histologic response rate of high-grade squamous intraepithelial lesions (HSIL) of the cervix after topical application of 5% imiquimod cream. METHODS: In this phase II trial, women with cervical HSIL (cervical intraepithelial neoplasia [CIN] 2-3) were randomly assigned to 250 mg of 5% imiquimod cream applied to the cervix weekly for 12 weeks, followed by loop electrosurgical excision procedure (LEEP) without preceding treatment. The sample size was calculated based on the HSIL regression rates previously reported by Grimm et al. The primary outcome was rate of histologic regression (to CIN 1 or less) in LEEP specimens. Prespecified secondary endpoints included surgical margin status and adverse events. Outcomes were stratified by human papillomavirus type and lesion grade (CIN 2 or CIN 3). Results were reported according to per protocol (PP) and intention-to-treat (ITT) analyses. RESULTS: Ninety women were enrolled: 49 in the experimental group and 41 in the control group. In the PP population, histologic regression was observed in 23 of 38 participants (61%) in the experimental group compared with 9 of 40 (23%) in the control group (P=.001). Surgical margins were negative for HSIL in 36 of 38 participants (95%) in the experimental group and 28 of 40 (70%) in the control group (P=.004). In the ITT population, rates of histologic regression also were significantly higher in the experimental group. Rates of adverse events in the experimental group were 74% (28/38) in the PP population and 78% (35/45) in the ITT population. Adverse events were mild, with abdominal pain being the most common. Three patients in the experimental group had grade 2 adverse events, including vaginal ulcer, vaginal pruritus with local edema, and moderate pelvic pain. CONCLUSION: Weekly topical treatment with imiquimod is effective in promoting regression of cervical HSIL. CLINICAL TRIAL REGISTRATION: ClinicalTrials.gov, NCT03233412.

Cervical lesion assessment using real-time microendoscopy image analysis in Brazil: The CLARA study.

We conducted a prospective evaluation of the diagnostic performance of high-resolution microendoscopy (HRME) to detect cervical intraepithelial neoplasia (CIN) in women with abnormal screening tests. Study participants underwent colposcopy, HRME and cervical biopsy. The prospective diagnostic performance of HRME using an automated morphologic image analysis algorithm was compared to that of colposcopy using histopathologic detection of CIN as the gold standard. To assess the potential to further improve performance of HRME image analysis, we also conducted a retrospective analysis assessing performance of a multi-task convolutional neural network to segment and classify HRME images. One thousand four hundred eighty-six subjects completed the study; 435 (29%) subjects had CIN Grade 2 or more severe (CIN2+) diagnosis. HRME with morphologic image analysis for detection of CIN Grade 3 or more severe diagnoses (CIN3+) was similarly sensitive (95.6% vs 96.2%, P = .81) and specific (56.6% vs 58.7%, P = .18) as colposcopy. HRME with morphologic image analysis for detection of CIN2+ was slightly less sensitive (91.7% vs 95.6%, P < .01) and specific (59.7% vs 63.4%, P = .02) than colposcopy. Images from 870 subjects were used to train a multi-task convolutional neural network-based algorithm and images from the remaining 616 were used to validate its performance. There were no significant differences in the sensitivity and specificity of HRME with neural network analysis vs colposcopy for detection of CIN2+ or CIN3+. Using a neural network-based algorithm, HRME has comparable sensitivity and specificity to colposcopy for detection of CIN2+. HRME could provide a low-cost, point-of-care alternative to colposcopy and biopsy in the prevention of cervical cancer.

Evaluation of human papillomavirus self-collection offered by community health workers at home visits among under-screened women in Brazil.

OBJECTIVE: To explore the acceptability of high-risk human papillomavirus self-testing, involving community health workers, for never/under-screened Brazilian women. Cervical cancer is the most common cause of cancer-related death among adult women in a large number of low-income and lower-middle-income countries, where it remains a major public health problem. High-risk human papillomavirus persistence is required for the development of cervical neoplasia. METHODS: The target population was all women aged 30+ from the list of families available in healthcare centre data, who had never been screened or were not screened in the previous 3 years (under-screened women), and who were living in the 17 cities included in this study. RESULTS: Of the 377 women included, 16.9% (n = 64) had never had a pap smear. Of all samples included in the study, 97.1% (n = 366) were considered adequate for evaluation, as 2.9% (n = 11) were considered invalid for all high-risk human papillomavirus types. Analysing these 366 samples, 9.6% (n = 35) of the women were infected by at least one high-risk human papillomavirus type and 90.4% (n = 331) had no infection with any high-risk type of the virus. CONCLUSIONS: Vaginal self-sampling is an adequate strategy to improve the effectiveness of the cervical cancer program by increasing screening in a high-risk group.

Methylation of the hsa-miR-124, SOX1, TERT, and LMX1A genes as biomarkers for precursor lesions in cervical cancer.

OBJECTIVES: The methylation profile of genes in precursor lesions in cervical cancer was characterized to improve screening techniques for high-grade intraepithelial neoplasia. METHODS: A total of 447 cervical cytology samples obtained from women who underwent colposcopy were examined. The cases were distributed as follows: (1) cervices without cervical intraepithelial neoplasia (CIN; n = 152); (2) cervices with a CIN grade of 1 (CIN 1; n = 147); and (3) cervices with a CIN grade of 2 or 3 (CIN 2/3; n = 148). The methylation pattern for a panel of 15 genes was analysed by quantitative methylation-specific PCR (qMSP) and compared between the groups (≤CIN 1 vs. CIN 2+). RESULTS: In the validation set, seven genes presented significantly different methylation profiles according to diagnosis, namely, DAPK1 (p = 0.001), EPB41L3 (p = 0.001), HIC1 (p = 0.028), hsa-miR-124-2 (p = 0.001), LMX1A (p = 0.001), SOX1 (p = 0.001), and TERT (p = 0.001). Six genes showed a significant increase in the frequency of methylation in the presence of hr-HPV, namely, DAPK1 (p = 0.001), EPB41L3 (p = 0.001), hsa-miR-124-2 (p = 0.001), LMX1A (p = 0.001), SOX1 (p = 0.001), and TERT (p = 0.001). The methylation of the hsa-miR-124 gene showed sensitivity and specificity (86.7% and 61.3%, respectively) similar to that of the HPV test (91.3% and 50.0%, respectively). The independent factors associated with the diagnosis of CIN 2+ and the methylation of the hsa-miR-124-2 (OR = 5.1), SOX1 (OR = 2.8), TERT (OR = 2.2), and LMX1A (OR = 2.0) genes were a positive test for hr-HPV (odds ratio [OR] = 5.5). CONCLUSIONS: Hypermethylation of the hsa-miR-124-2, SOX1, TERT, and LMX1A genes may be a promising biomarker for precursor lesions in cervical cancer regardless of the hr-HPV status.

Diagnosing Cervical Neoplasia in Rural Brazil Using a Mobile Van Equipped with In Vivo Microscopy: A Cluster-Randomized Community Trial.

Cervical cancer is a leading cause of death in underserved areas of Brazil. This prospective randomized trial involved 200 women in southern/central Brazil with abnormal Papanicolaou tests. Participants were randomized by geographic cluster and referred for diagnostic evaluation either at a mobile van upon its scheduled visit to their local community, or at a central hospital. Participants in both arms underwent colposcopy, in vivo microscopy, and cervical biopsies. We compared rates of diagnostic follow-up completion between study arms, and also evaluated the diagnostic performance of in vivo microscopy compared with colposcopy. There was a 23% absolute and 37% relative increase in diagnostic follow-up completion rates for patients referred to the mobile van (102/117, 87%) compared with the central hospital (53/83, 64%; P = 0.0001; risk ratio = 1.37, 95% CI, 1.14-1.63). In 229 cervical sites in 144 patients, colposcopic examination identified sites diagnosed as cervical intraepithelial neoplasia grade 2 or more severe (CIN2+; 85 sites) with a sensitivity of 94% (95% CI, 87%-98%) and specificity of 50% (95% CI, 42%-58%). In vivo microscopy with real-time automated image analysis identified CIN2+ with a sensitivity of 92% (95% CI, 84%-97%) and specificity of 48% (95% CI, 40%-56%). Women referred to the mobile van were more likely to complete their diagnostic follow-up compared with those referred to a central hospital, without compromise in clinical care. In vivo microscopy in a mobile van provides automated diagnostic imaging with sensitivity and specificity similar to colposcopy. Cancer Prev Res; 11(6); 359-70. ©2018 AACR.

The Role of Self-Collection by Vaginal Lavage for the Detection of HPV and High-Grade Intraepithelial Neoplasia.

OBJECTIVE: To compare the results of cervical cytology and high-risk HPV tests using samples obtained using two different collection modalities in a population of Brazilian women: self-collection (vaginal lavage) and cervical Pap testing. METHODS: We enrolled 204 women who were aged 18-64 years and had previously obtained abnormal cervical cytology test results; 83.8% of them agreed to participate. The sample was divided into two aliquots: one for the cytological study and one for the molecular analysis of high-risk HPV. RESULTS: Fifty-eight percent of the participants preferred to utilize self-collection as an alternative screening method. However, we noticed that the HPV positivity rate was significantly lower in self-collected samples when compared to those obtained using the conventional collection method (p = 0.035). The cytology tests of the samples obtained via self-collection were sensitive and had a positive predictive value and an area under the curve (AUC) that were significantly lower than those of the Pap test. However, the specificity and negative predictive value of these tests were similar. When compared with the HPV test, the self-collected samples demonstrated lower accuracy in predicting high-grade cervical intraepithelial neoplasia or worse, with a significantly lower sensitivity, positive predictive value, and AUC than the cervical Pap test samples. CONCLUSION: Self-collection by vaginal lavage is simple and well accepted by women. Due to its limitations, however, self-collection by lavage should be utilized with caution.

A Low-Cost HPV Immunochromatographic Assay to Detect High-Grade Cervical Intraepithelial Neoplasia.

OBJECTIVE: To evaluate the reproducibility and accuracy of the HPV16/18-E6 test. METHODS: The study population was comprised of 448 women with a previously abnormal Pap who were referred to the Barretos Cancer Hospital (Brazil) for diagnosis and treatment. Two cervical samples were collected immediately before colposcopy, one for the hr-HPV-DNA test and cytology and the other for the HPV16/18-E6 test using high-affinity monoclonal antibodies (mAb). Women with a histologic diagnosis of cervical intraepithelial neoplasia grade 2 or 3 were considered to be positive cases. Different strategies using a combination of screening methods (HPV-DNA) and triage tests (cytology and HPV16/18-E6) were also examined and compared. RESULTS: The HPV16/18-E6 test exhibited a lower positivity rate compared with the HPV-DNA test (19.0% vs. 29.3%, p<0.001) and a moderate/high agreement (kappa = 0.68, 95%CI: 0.60-0.75). It also exhibited a significantly lower sensitivity for CIN2+ and CIN3+ detection compared to the HPV-DNA test and a significantly higher specificity. The HPV16/18-E6 test was no different from cytology in terms of sensitivity, but it exhibited a significantly higher specificity in comparison to ASCH+. A triage test after HPV-DNA detection using the HPV16/18-E6 test exhibited a significantly higher specificity compared with a triage test of ASCH+ to CIN2+ (91.8% vs. 87.4%, p = 0.04) and CIN3+ (88.6% vs. 84.0%, p = 0.05). CONCLUSION: The HPV16/18-E6 test exhibited moderate/high agreement with the HPV-DNA test but lower sensitivity and higher specificity for the detection of CIN2+ and CIN3+. In addition, its performance was quite similar to cytology, but because of the structural design addressed for the detection of HPV16/18-E6 protein, the test can miss some CIN2/3+ lesions caused by other high-risk HPV types.

Comparison of the Cervex-Brush® Combi and the Cytobrush+Ayres Spatula Combination for Cervical Sampling in Liquid-Based Cytology.

OBJECTIVES: To compare the performance of two cervical collection devices (Cytobrush+Ayres spatula and Cervex-Brush® Combi) for cellular sampling, transformation zone representation and accuracy in diagnosing cervical intraepithelial neoplasia (CIN) 2+. METHODS: Cervical samples were collected from patients referred to the colposcopy unit of the Barretos Cancer Hospital between September 2013 and October 2014 using one of the two sampling devices. Additionally, colposcopy was performed with or without cervical biopsy and/or endocervical curettage. RESULTS: Biopsy was performed in 670 of the 1,235 patients submitted to colposcopy (54.2%). The Cervex-Brush® Combi was more effective than the Cytobrush with respect to endocervical cells sampling (82.7% versus 74.6%; p = 0.001). Sensitivity was also higher with the Cervex-Brush® Combi (48.6% versus 33.9%; p = 0.023) for predicting CIN2+ when high-grade squamous intraepithelial lesions were detected at cytology. CONCLUSIONS: Cervex-Brush® Combi was more effective than Cytobrush+Ayres Spatula for endocervical cells sampling and also had a slightly higher accuracy in predicting histologically CIN2+ lesions in patients with diagnosis of HSIL in cytology.

Can the careHPV test performed in mobile units replace cytology for screening in rural and remote areas?

BACKGROUND: Human papillomavirus (HPV) DNA testing can be crucial for women who have limited access to traditional screening. The current study compared the results obtained through HPV DNA testing with those obtained through cytology-based screening. METHODS: A total of 3068 women aged 18 to 85 years were enrolled in an opportunistic cervical cancer screening program developed by the Barretos Cancer Hospital and performed by a team of health professionals working within a mobile unit from March to December 2012, followed by statistical analyses. For each patient, 2 different cervical samples were collected and preserved in a careHPV assay and SurePath medium, respectively. RESULTS: High-risk HPV (hr-HPV) DNA was detected in 10.0% of women, with the majority (86.7%) demonstrating no abnormal Papanicolaou test results. The following cytological samples were found to be hr-HPV positive: 8.2% of the normal samples; 39.4% of the samples with atypical squamous/glandular cells of undetermined significance; 38.5% of the samples with atypical squamous/glandular cells of undetermined significance, cannot exclude high-grade lesion; 55.3% of the samples with low-grade squamous intraepithelial lesions; and 100% of the samples with high-grade squamous intraepithelial lesions. Colposcopy examinations were performed among 33.4% of the women with positive results on at least 1 of the tests (HPV DNA positive and/or cytology with atypical squamous/glandular cells of undetermined significance, cannot exclude high-grade lesion or high-grade squamous intraepithelial lesions), and 59.5% of these women underwent biopsies. Among these samples, 18.2% were confirmed as cervical intraepithelial neoplasia. CONCLUSIONS: The careHPV test was demonstrated to be a feasible alternative to primary screening in low-resource settings accessed through the use of mobile units. Cancer Cytopathol 2016;124:581-8. © 2016 American Cancer Society.