Can visual inspection with acetic acid under magnification substitute colposcopy in detecting cervical intraepithelial neoplasia in low-resource settings?

Accuracy of Smartphone Images of the Cervix After Acetic Acid Application for Diagnosing Cervical Intraepithelial Neoplasia Grade 2 or Greater in Women With Positive Cervical Screening: A Systematic Review and Meta-Analysis

PURPOSE

Smartphones are used in cervical screening for visual inspection after acetic acid or Lugol's iodine (VIA/VILI) application to capture and share images to improve the sensitivity and interobserver variability of VIA/VILI. We undertook a systematic review and meta-analysis assessing the diagnostic accuracy of smartphone images of the cervix at the time of VIA/VILI (termed S-VIA) in the detection of precancerous lesions in women undergoing cervical screening.

METHODS

This systematic review was conducted in accordance with Preferred Reporting Items for Systematic Reviews and Meta-Analyses guidelines. Studies from January 1, 2010, to June 30, 2020, were assessed. MEDLINE/PubMed, Embase, CINAHL, Cochrane, and LILACS were searched. Cohort and cross-sectional studies were considered. S-VIA was compared with the reference standard of histopathology. We excluded studies where additional technology was added to the smartphone including artificial intelligence, enhanced visual assessment, and other algorithms to automatically diagnose precancerous lesions. The primary outcome was the accuracy of S-VIA for the diagnosis of cervical intraepithelial neoplasia grade 2 or greater (CIN 2+). Data were extracted, and we plotted the sensitivity, specificity, negative predictive value, and positive predictive value of S-VIA using forest plots. This study was prospectively registered with The International Prospective Register of Systematic Reviews:CRD42020204024.

RESULTS

Six thousand three studies were screened, 71 full texts assessed, and eight studies met criteria for inclusion, with six included in the final meta-analysis. The sensitivity of S-VIA for the diagnosis of CIN 2+ was 74.56% (95% CI, 70.16 to 78.95; I² 61.30%), specificity was 61.75% (95% CI, 56.35 to 67.15; I² 95.00%), negative predictive value was 93.71% (95% CI, 92.81 to 94.61; I² 0%), and positive predictive value was 26.97% (95% CI, 24.13 to 29.81; I² 61.3%).

CONCLUSION

Our results suggest that S-VIA has accuracy in the detection of CIN 2+ and may provide additional support to health care providers delivering care in low-resource settings.

To Evaluate the Role of p16Ink4a Immunocytochemistry for Detection of CIN2+ in Women Detected Screen Positive by Visual Inspection Using Acetic Acid

Objective:

To evaluate the role of p16^Ink4a immunostaining for the detection of cervical intraepithelial neoplasia (CIN2+) in women who had a positive screening test using visual inspection with acetic acid (VIA).

Methods:

Opportunistic screening of women (30–50 years) coming to the gynecology clinic by VIA was performed; the screen-positive women were included in the study which had the institutional review board (IRB) approval. A cytology slide for p16^Ink4a immunostaining, colposcopy, and biopsy was then performed sequentially. The sensitivity, specificity, positive predictive value (PPV), and negative predictive value (NPV) of p16^Ink4a immunocytochemistry were evaluated with histopathology as the gold standard.

Results:

p16^Ink4a positivity showed a linear correlation with the increasing grade of CIN. p16^Ink4a positivity was seen in 6% of CIN 1, 80% of CIN 2, 100% of CIN 3, and squamous cell carcinoma. The sensitivity and specificity of p16^Ink4a immunocytochemistry for detecting CIN 2 or more was 87.5% (95%CI 61.65–98.45) and 97.06% (95%CI 84.67–99.93). Colposcopy had an equal sensitivity of 87.5% (95% CI 61.65–98.45) and specificity of 50% (95% CI 32.43–67.57), respectively.

Conclusion:

With high sensitivity and specificity, p16^Ink4a immunocytochemistry could be a viable option for triaging VIA-positive women.

Comparison of the AV Magnivisualizer device with colposcopy to detect cervical intraepithelial neoplasia using the Swede scoring system

OBJECTIVE

To compare the AV Magnivisualizer with colposcopy to detect cervical intraepithelial neoplasia (CIN) using the Swede scoring system.

METHODS

Cross-sectional study conducted in a tertiary care hospital from May 2017 to March 2018. One hundred women with positive results at visual inspection with acetic acid underwent cervical inspection using the Magnivisualizer followed by a colposcope. Biopsies were taken if the Swede score was greater than 4. Pregnant women, women with an obvious cervical growth, acute cervicitis, or prior cervical surgery were excluded. Diagnostic accuracy of the Magnivisualizer and colposcope was calculated for high-grade lesions (CIN 2/CIN 2+) and agreement was compared between the two modalities.

RESULTS

The sensitivity, specificity, and positive and negative predictive values of the Magnivisualizer were 88.2%, 70.0%, 50.0%, and 94.6%, respectively, to detect high-grade lesions at a Swede score cutoff of 5 or more. The area under the curve for the Magnivisualizer was 0.80 (95% CI, 0.67-0.92), which was comparable with colposcopy (AUC 0.86; 95% CI, 0.76-0.96). There was very good agreement between the Magnivisualizer and colposcopy (κ=0.865, P<0.001) for high-grade lesions.

CONCLUSION

The Magnivisualizer had high diagnostic accuracy to detect high-grade CIN in screen-positive women, which was comparable with colposcopy.

Clinical, laboratory and epidemiological aspects of HPV infection in a low-income population from South Bahia, Brazil

The aim of this study was to determine the prevalence and risk factors for human papillomavirus (HPV) infection in the Southern region of the State of Bahia, evaluating the performance of alternative complementary methods for cervical lesion detection. Cervical samples from women who attended healthcare units were collected and diagnosed by visual inspection, cervical cytology and nested polymerase chain reaction (PCR). Moreover, hemi-nested PCR was performed to detect different HPV genotypes. The prevalence of HPV infection was 47·7%, with genotype 16 detected in most cases. Infection was associated with dyspareunia and bleeding (P < 0·001, odds ratio (OR) 5·6, 95% confidence interval (CI) 2·815-11·14) and hormonal contraceptive use (P = 0·007, OR 2·33, 95% CI 1·25-4·34). There was a positive correlation between positive PCR and positive visual inspection, cervical cytology and symptoms reported. Furthermore, visual inspection was twice as specific, and had a greater positive predictive value than cytology. We showed a high prevalence of HPV infection in Southern Bahia, with HPV 16 being the most common type, and visual inspection being most effective at detecting HPV lesions, corroborating the suggestion that it can be applied in routine gynecologic examinations for low-income populations.

Design of a Novel Low Cost Point of Care Tampon (POCkeT) Colposcope for Use in Resource Limited Settings

Introduction

Current guidelines by WHO for cervical cancer screening in low- and middle-income countries involves visual inspection with acetic acid (VIA) of the cervix, followed by treatment during the same visit or a subsequent visit with cryotherapy if a suspicious lesion is found. Implementation of these guidelines is hampered by a lack of: trained health workers, reliable technology, and access to screening facilities. A low cost ultra-portable Point of Care Tampon based digital colposcope (POCkeT Colposcope) for use at the community level setting, which has the unique form factor of a tampon, can be inserted into the vagina to capture images of the cervix, which are on par with that of a state of the art colposcope, at a fraction of the cost. A repository of images to be compiled that can be used to empower front line workers to become more effective through virtual dynamic training. By task shifting to the community setting, this technology could potentially provide significantly greater cervical screening access to where the most vulnerable women live. The POCkeT Colposcope’s concentric LED ring provides comparable white and green field illumination at a fraction of the electrical power required in commercial colposcopes. Evaluation with standard optical imaging targets to assess the POCkeT Colposcope against the state of the art digital colposcope and other VIAM technologies.

Results

Our POCkeT Colposcope has comparable resolving power, color reproduction accuracy, minimal lens distortion, and illumination when compared to commercially available colposcopes. In vitro and pilot in vivo imaging results are promising with our POCkeT Colposcope capturing comparable quality images to commercial systems.

Conclusion

The POCkeT Colposcope is capable of capturing images suitable for cervical lesion analysis. Our portable low cost system could potentially increase access to cervical cancer screening in limited resource settings through task shifting to community health workers.

Accuracy of visual inspection with acetic acid in detecting high-grade cervical intraepithelial neoplasia in pre- and post-menopausal Thai women with minor cervical cytological abnormalities

PURPOSE

To determine the accuracy of visual inspection with acetic acid (VIA) in detecting high-grade cervical intraepithelial neoplasia (CIN) in pre- and post-menopausal women with atypical squamous cells of undetermined significance (ASC-US) and low grade squamous intraepithelial lesion (LSIL) Papanicolaou (Pap) smears.

MATERIALS AND METHODS

Two hundred women (150 pre-menopausal and 50 post-menopausal) with ASC- US and LSIL cytology who attended the colposcopy clinic, Thammasat University Hospital, between March 2013 and August 2014 were included. All women underwent VIA testing and colposcopy by gynecologic oncologists. Diagnostic values of VIA testing including sensitivity, specificity, positive predictive value (PPV) and negative predictive value (NPV) for detecting high-grade CIN were determined using the histopathology obtained from colposcopic-directed biopsy as a gold standard.

RESULTS

VIA testing was positive in 54/150 (36%) pre-menopausal women and 5/50 (10%) post-menopausal women. Out of 54 pre-menopausal women with positive VIA testing, 15 (27.8%) had high-grade CIN and 39 (72.2%) had either CIN 1 or insignificant pathology. Ten (10.4%), 43 (44.8%) and 43 (44.8%) out of the remaining 96 pre-menopausal women with negative VIA testing had high- grade CIN, CIN 1 and insignificant pathology, respectively. Out of 5 post-menopausal women with positive VIA testing, there were 4 (80%) women with high-grade CIN, and 1 (20%) women with insignificant pathology. Out of 45 VIA-negative post-menopausal women, 42 (93.3%) women had CIN 1 and insignificant pathology, and 3 (6.7%) had high-grade CIN. Sensitivity, specificity, PPV and NPV of the VIA testing were 59.4%, 76.2%, 32.2% and 90.8%, respectively (60%, 68.8%, 27.8% and 89.6% in pre-menopausal women and 57.1%, 97.7%, 80% and 93.3% in post-menopausal women).

CONCLUSIONS

VIA testing may be used as a screening tool for detecting high-grade CIN in women with minor cervical cytological abnormalities in a low-resource setting in order to lower the rate of colposcopy referral.

Cervical cancer: Can it be prevented?

Cervical cancer prevention requires a multipronged approach involving primary, secondary and tertiary prevention. The key element under primary prevention is human papilloma virus (HPV) vaccination. So far, only prophylactic HPV vaccines which prevent HPV infection by one or more subtypes are commercially available. Therapeutic HPV vaccines which aid in clearing established infection are still under trial. Secondary prevention entails early detection of precancerous lesions and its success is determined by the population coverage and the efficacy of the screening technique. A number of techniques are in use, including cytology, visual inspection (using the naked eye, magnivisualizer, acetic acid and Lugol’s iodine), HPV testing and a combination of these methods. Updated screening guidelines have been advocated by the American Cancer Society in light of the role of HPV on cervical carcinogenesis. Recent research has also focussed on novel biomarkers that can predict progression to cancer in screen positive women and help to differentiate those who need treatment from those who can be left for follow-up. Last but not the least, effective treatment of precancerous lesions can help to reduce the incidence of invasive cervical cancer and this constitutes tertiary prevention. A combination of these approaches can help to prevent the burden of cervical cancer and its antecedent morbidity and mortality, but all of these are not feasible in all settings due to resource and allocation constraints. Thus, all countries, especially low and middle income ones, have to determine their own cocktail of approaches that work before we can say with certainty that yes, cervical cancer can be prevented.

Performance of a low cost magnifying device, Magnivisualizer, versus colposcope for detection of pre-cancer and cancerous lesions of uterine cervix

Objective

To assess the performance of a low cost magnifying device (Magnivisualizer) compared to a standard optical colposcope for detection of precancerous and cancerous lesions of the uterine cervix.

Methods

A total of 659 consecutive symptomatic women attending a gynecologic outpatient clinic underwent unaided visual inspection followed by cytology, visual inspection of the cervix using 5% acetic acid (VIA), and VIA under magnification (VIAM) with the Magnivisualizer. All women, independently of test results, were referred for colposcopic examination. Colposcopic-directed biopsies were obtained from all positive lesions and compared to positive VIAM cases.

Results

The detection rate for VIA positive lesions was 12% (134/659), while it was 29% for VIAM positive lesions (191/659). The sensitivities of detection of cervical intraepithelial neoplasia (CIN) 2 and higher lesions were 61.7% for VIA, 88.3% for VIAM, and 86.7% for colposcopy, with a specificity of 58.5% for VIA, 55.8% for VIAM, and 90.4% for colposcopy. The performance of colposcopy and VIAM was moderate (κ, 0.48; 95% confidence interval [CI], 0.41 to 0.54) for detection of CIN 1 and higher lesions and excellent (κ, 0.87; 95% CI, 0.82 to 0.94) for detection of CIN 2 and higher lesions.

Conclusion

In low resource settings, where colposcopic facilities are not available at the community level, a simple low-cost, handheld Magnivisualizer can be considered a valid option for detection of cervical precancerous and cancerous lesions. However, it cannot replace traditional colposcopy because it has a low specificity that results in many unnecessary biopsies.