ABCD criteria to improve visual inspection with acetic acid (VIA) triage in HPV-positive women: a prospective study of diagnostic accuracy

The Diagnostic Accuracy of Electrical Impedance Spectroscopy-Assisted Colposcopy, HPV mRNA Test, and P16/Ki67 Immunostaining as CIN2+ Predictors in Greek Population

OBJECTIVE

To evaluate the diagnostic accuracy of Electrical Impedance Spectroscopy (EIS)-assisted colposcopy in detecting CIN2+ Greek women towards standalone colposcopy, HPV mRNA testing, and p16/Ki67 immunostaining.

METHODS

We conducted a cross-sectional observational study at the Cervical Pathology Clinic of the 2nd Obstetrics-Gynecology University Department of Hippokration Hospital Thessaloniki involving 316 patients from January 2022 to August 2023. All participants provided liquid-based cervical samples for cytology, HPV mRNA testing, and p16/Ki67 immunostaining.

MAIN OUTCOME MEASURES

Subsequently, participants underwent both standalone colposcopy and EIS/ZedScan-assisted colposcopy, followed by cervical punch biopsies.

RESULTS

The incorporation of EIS significantly enhanced the sensitivity of colposcopy, increasing it from 54.17% to 100%, equivalent to that of HPV mRNA testing and p16/Ki67 immunostaining, while achieving a high specificity (95.45%). The specificities observed with EIS/ZedScan-assisted and standalone colposcopy were notably superior to those of HPV-related biomarkers (HPV mRNA test and p16/Ki67 immunostaining). When compared to standalone colposcopy, HPV mRNA testing, and p16/Ki67 immunostaining, EIS/ZedScan-assisted colposcopy demonstrated the most favorable combination of Positive and Negative Predictive Values, at 90.57% and 100%, respectively. The inclusion of EIS/ZedScan in colposcopy led to the detection of 44 additional cases of true CIN2+ (100% of the total CIN2+ confirmed histologically) that were missed by standalone colposcopy. This discovery suggests a 45.83% increase in the detection of CIN2+ cases.

CONCLUSIONS

The integration of EIS with colposcopy has demonstrated effectiveness in detecting cervical lesions, resulting in a significant detection increase of CIN2+ cases while offering optimal levels of sensitivity, specificity, and predictive values for CIN2+ detection.

Task-shifting for point-of-care cervical cancer prevention in low- and middle-income countries: a case study from Uganda

Cervical cancer remains the leading cause of female cancer deaths in sub-Saharan Africa. This is despite cervical cancer being both preventable and curable if detected early and treated adequately. This paper reports on a series of action-research 'cycles' designed to progressively integrate a comprehensive, task-shifted, point-of-care, prevention program in a community-based public health facility in Uganda. The work has been undertaken through a UK-Ugandan Health Partnership coordinated by Knowledge for Change, a UK-registered Charity. The intervention demonstrates the effectiveness of task-shifting responsibility to Community Health Workers combined with the use of Geographic Information Systems to strategically guide health awareness-raising and the deployment of medical devices supporting respectful and sustainable point-of-care screen-and-treat services. The integration of this with public human immunodeficiency virus services demonstrates the ability to engage hard-to-reach 'key populations' at greatest risk of cervical cancer. The findings also demonstrate the impact of external influences including the Results Based Financing approach, adopted by many foreign Non-Governmental Organizations. The model presents opportunities for policy transfer to other areas of health promotion and prevention with important lessons for international Health partnership engagement. The paper concludes by outlining plans for a subsequent action-research cycle embracing and evaluating the potential of Artificial Intelligence to enhance service efficacy.

Use of risk-based cervical screening programs in resource-limited settings

Cervical cancer screening and management in the U.S. has adopted a risk-based approach. However, the majority of cervical cancer cases and deaths occur in resource-limited settings, where screening and management are not widely available. We describe a conceptual model that optimizes cervical cancer screening and management in resource-limited settings by utilizing a risk-based approach. The principles of risk-based screening and management in resource limited settings include (1) ensure that the screening method effectively separates low-risk from high-risk patients; (2) directing resources to populations at the highest cancer risk; (3) screen using HPV testing via self-sampling; (4) utilize HPV genotyping to improve risk stratification and better determine who will benefit from treatment, and (5) automated visual evaluation with artificial intelligence may further improve risk stratification. Risk-based screening and management in resource limited settings can optimize prevention by focusing triage and treatment resources on the highest risk patients while minimizing interventions in lower risk patients.

Performance of visual inspection of the cervix with acetic acid (VIA) for triage of HPV screen-positive women: results from the ESTAMPA study

VIA is recommended for triage of HPV-positive women attending cervical screening. In the multicentric ESTAMPA study, VIA performance for detection of cervical intraepithelial neoplasia grade 3 or worse (CIN3+) among HPV-positive women was evaluated. Women aged 30-64 years were screened with HPV testing and cytology and referred to colposcopy if either test was positive. At colposcopy visit, study-trained midwives/nurses/GPs performed VIA ahead of colposcopy. VIA was considered positive if acetowhite lesions were observed in or close to the transformation zone. Ablative treatment eligibility was assessed for VIA positives. Performance indicators were estimated. Three thousand one hundred and forty-two HPV-positive women were included. Sensitivity for CIN3+ was 85.9% (95% CI 81.2-89.5) among women <50 years and, although not significant, slightly lower in women 50+ (78.0%, 95% CI 65.9-86.6). Overall specificity was 58.6% (95% CI 56.7-60.5) and was significantly higher among women 50+ (70.3%, 95% CI 66.8-73.5) compared to women <50 (54.3%, 95% CI 52.1-56.5). VIA positivity was lower among women 50+ (35.2%, 95% CI 31.9-38.6) compared to women <50 (53.2, 95% CI 51.1-55.2). Overall eligibility for ablative treatment was 74.5% and did not differ by age. VIA sensitivity, specificity, and positivity, and ablative treatment eligibility varied highly by provider (ranges: 25%-95.4%, 44.9%-94.4%, 8.2%-65.3%, 0%-98.7%, respectively). VIA sensitivity for cervical precancer detection among HPV-positive women performed by trained providers was high with an important reduction in referral rates. However, scaling-up HPV screening triaged by VIA will be challenging due to the high variability of VIA performance and providers' need for training and supervision.

Comparison of human papillomavirus-based cervical cancer screening strategies in Tanzania among women with and without HIV

Cervical cancer is the most common female cancer in Eastern Africa, and the World Health Organization (WHO) recommends human papillomavirus (HPV)-based screening as a key element to eliminate the disease. In this cross-sectional study from Tanzania, we compared nine HPV-based cervical cancer screening strategies, including HPV testing at standard cut-off; HPV testing at increased viral load cut-offs; HPV testing with partial/extended genotyping, and HPV testing with visual inspection with acetic acid (VIA). We pooled data collected during 2008 to 2009 and 2015 to 2017 from 6851 women aged 25 to 65. Cervical cytology samples were HPV tested with Hybrid Capture 2, and HPV positive samples were genotyped with INNO-LiPA Extra II. Human immunodeficiency virus (HIV) testing and VIA were done according to local standards. We calculated sensitivity, specificity, positive and negative predictive value of screening strategies, with high-grade cytological lesions as reference, separately for women with and without HIV. HPV testing at standard cut-off (1.0 relative light units [RLU]) had highest sensitivity (HIV+: 97.8%; HIV-: 91.5%), but moderate specificity (HIV+: 68.1%; HIV-: 85.7%). Increasing the cut-off for HPV positivity to higher viral loads (5.0/10.0 RLU) increased specificity (HIV+: 74.2%-76.5%; HIV-: 89.5%-91.2%), with modest sensitivity reductions (HIV+: 91.3%-95.7%; HIV-: 83.5%-87.8%). Limiting test positivity to HPV types 16/18/31/33/35/45/52/58 improved specificity while maintaining high sensitivity (HIV+: 90.2%; HIV-: 81.1%). Triage with VIA and/or partial genotyping for HPV16/18 or HPV16/18/45 had low sensitivities (≤65%). In conclusion, HPV testing alone, or HPV testing with extended genotyping or increased viral load cut-offs, may improve cervical cancer screening in Sub-Saharan Africa.

Transformation Zone Assessment Using Visual Inspection With Acetic Acid Before and After Thermal Ablation: Implications for Follow-Up

PURPOSE

Thermal ablation (TA) has become the conventional method for treatment of precancerous cervical lesions in low-resource settings. After TA, both the squamocolumnar junction (SCJ) and the transformation zone (TZ) may be subject to change. Our aim was to evaluate SCJ and TZ variability after TA.

METHODS

Study data were collected in a large prospective trial of a cervical cancer screening campaign in Cameroon. For each patient, two sets of cervical photos (native and with acetic acid) were taken before and 6-12 months after TA. The SCJ and TZ were evaluated independently by three observers according to the WHO nomenclature. When discordances were observed between the type of TZ and SCJ selected by each observer, a corrected TZ was established on the basis of the SCJ categorization. Interobserver agreement for TZ interpretation was evaluated using Cohen's kappa coefficient for agreement between two observers and Fleiss' kappa between three observers.

RESULTS

Fifty consecutive participants were included in the analysis. Seventy-six percent were interpreted as TZ1-2, and 24% as TZ3 before TA. In 56% of cases, the entire SCJ could not be entirely visualized after TA, thus being recategorized as TZ3. Interobserver agreement was fair for diagnosis before TA (Kappa coefficient, 0.34; 95% CI, 0.27 to 0.45) and moderate for diagnosis after TA (Kappa coefficient, 0.40; 95% CI, 0.30 to 0.50). After TA, 36% progressed from TZ1-2 to TZ3, with a moderate interobserver agreement (Kappa coefficient, 0.44; 95% CI, 0.40 to 0.54).

CONCLUSION

We observed a shift of the SCJ into the endocervical canal after TA. A significant proportion of participants had TZ 3 after treatment, raising the question of visual inspection with acetic acid's applicability as a first-line follow-up examination method after TA.

Utility of extended HPV genotyping for the triage of self-sampled HPV-positive women in a screen-and-treat strategy for cervical cancer prevention in Cameroon: a prospective study of diagnostic accuracy

OBJECTIVE

To explore the utility of extended Human Papillomavirus (HPV) genotyping to detect cervical intraepithelial neoplasia grade 2 or more (CIN2+) in a 'screen-and-treat' strategy for HPV-positive women in low-resource settings.

DESIGN

Prospective study of diagnostic accuracy.

SETTING

The study took place in West Cameroon between September 2018 and March 2020.

PARTICIPANTS

2014 women were recruited. Asymptomatic, non-pregnant women aged 30-49 years without history of CIN treatment, anogenital cancer or hysterectomy were eligible.

INTERVENTIONS

Participants performed self-sampling for HPV testing with GeneXpert followed by visual inspection with acetic acid and Lugol's iodine (VIA) triage before treatment if required.

MAIN OUTCOME MEASURES

Liquid-based cytology, biopsies and endocervical brushing were performed in HPV-positive women as quality control. We assessed the detection rate of CIN2+ by HPV genotyping (two pools of genotypes obtained from the Xpert system, pool_1 (HPV 16, 18, 45) and pool_2 (HPV 16, 18, 45, 31, 33, 35, 52, 58)), VIA and cytology.

RESULTS

382 (18.2%) women were HPV-positive among which 11.5% (n=44) were CIN2+. Of those 44 participants, 41 were triaged positive by extended genotyping, versus 35 by VIA and 33 by cytology. Overall, triage positivity was of 68.4% for extended genotyping, 59.3% for VIA and 14.8% for cytology, with false positive rates of 83.4%, 84.1% and 37.7%, respectively. Extended genotyping had a higher sensitivity for CIN2+ detection (93.2%, CI: 81.3 to 98.6) than VIA (79.5%, CI: 64.7 to 90.2, p=0.034) and cytology (75.0%, CI: 59.7 to 86.8, p=0.005). No significant difference was observed in the overtreatment rate in triaged women by extended genotyping or VIA (9.9%, CI: 8.6 to 11.3, and 8.8%, CI: 7.7 to 10.1), with a ratio of 6.0 and 6.3 women treated per CIN2+ diagnosed.

CONCLUSION

Triage of HPV-positive women with extended HPV genotyping improves CIN2+ detection compared with VIA with a minor loss of specificity and could be used to optimize the management of HPV-positive women.

TRIAL REGISTRATION NUMBER

NCT03757299.