Cervical cancer screening in low- and middle-income countries: A systematic review of economic evaluation studies

Economic assessments are relevant to support the decision to incorporate more cost-effective strategies to reduce Cervical Cancer (CC) mortality. This systematic review analyzes the economic evaluation studies of CC prevention strategies (HPV DNA-based tests and conventional cytology) in low- and middle-income countries. Medline, EMBASE, CRD, and LILACS were searched for economic evaluation studies that reported cost and effectiveness measures of HPV DNA-based tests for CC screening and conventional cytology in women, without age, language, or publication date restrictions. Selection and data extraction were carried out independently. For comparability of results, cost-effectiveness measures were converted to international dollars (2019). Report quality was assessed using the CHEERS checklist. The Dominance Matrix Ranking (DRM) was used to analyze and interpret the results. The review included 15 studies from 12 countries, with cost-effectiveness analyzes from the health system's perspective and a 3% discount rate. The strategies varied in age and frequency of screening. Most studies used the Markov analytical model, and the cost-benefit threshold was based on the per capita GDP of each country. The sensitivity analysis performed in most studies was deterministic. The completeness of the report was considered sufficient in most of the items evaluated by CHEERS. The Dominance Interpretation (DRM) varied; in 6 studies, the HPV test was dominant, 5 studies showed a weak dominance evaluating greater effectiveness of the HPV test at a higher cost, yet in 2 studies conventional cytology was dominant. Although the context-dependent nature of economic evaluations, this review points out the challenge of methodological standardization in the analytical models.

Concordance of HPV, conventional smear, colposcopy, and conization results in cervical dysplasia

BACKGROUND

Cervical cancer screening algorithms are increasingly focused on Human Papillomavirus (HPV)-based screening while the accuracy of using abnormal cytological findings to detect dysplastic lesions still remains important. This retrospective study correlated the results of conventional cervical cytology, colposcopy guided biopsy, and cold knife conization (CKC) procedures performed in a tertiary center.

MATERIALS AND METHODS

Data from 9399 patients who underwent screening with conventional cervical cytology between 2010 and 2019 was obtained from the hospital registry. Abnormal cervical cytology and high-risk HPV DNA genotypes were recorded and their colposcopic and CKC pathology was determined.

RESULTS

Two hundred and ninety two patients underwent colposcopy for abnormal cervical cytology and/or high-risk HPV positivity. One hundred and twenty three patients were positive for High-risk HPV. Abnormal cervical cytology was detected in 216 patients. The most common cytological anomaly was atypical squamous cells of undetermined significance (ASCUS) found in 9399 patients (1.39%). It was determined that conventional cytology had a sensitivity of 70.8% and a specificity of 62.2% for the detection of low-grade lesions, while it had a sensitivity of 72.4% and a specificity of 86.0% for the detection of high-grade lesions. CKC was applied to 68 patients who were diagnosed with high-grade squamous intraepithelial lesions (HSIL) as a result of the colposcopy. As a result of CKC, a high-grade lesion was detected in 73.5% of these patients.

CONCLUSION

Conventional cervical cytology and colposcopy exhibited higher accuracy as the severity of lesions increased. Detection of HPV may prevent unnecessary surgical procedures, especially with ASCUS.

Value of CCNA1 promoter methylation in triaging ASC-US cytology

BACKGROUND

<br />Using HPV testing to triage ASC-US still has some problems of unnecessary colposcopy in many cases. A previous study reported that methylation of CCNA1, a tumor suppressor gene, can differentiate between low and high grade lesions. This study was designed to evaluate the diagnostic values and application of CCNA1 methylation in the patients with ASC-US group.<br />Materials and methods:<br />Cross sectional analytic study was conducted in the patients with <br />ASC-US cytology. HPV DNA testing and CCNA1 promoter methylation testing were performed. The patients were sent for colposcopic examination and biopsy. Biopsy results were considered as gold standard. Diagnostic test of HPV test and CCNA1 methylation test were calculated for sensitivity, specificity, negative predictive value (NPV), positive predictive value (PPV), likelihood ratio for test positive and negative and 95% confidence interval.<br />Results:<br />One hundred and seventy patients were enrolled. Mean age was 39.7 years old. HR-HPV was positive in 70% of the patients. HPV type 16, type 18 and non-16,18 were 12.4%, 4.7% and 42.4%, respectively. CIN2+ were found in 12.4% (21 cases). CCNA1 promoter methylation was positive in 5 cases. CCNA1 had high specificity 99.3%, NPV 89.2% and PPV 80% in detection of CIN2+ but sensitivity was 19%. Likelihood ratio for positive test was 28.4 and likelihood ratio for negative test was 0.8. HPV test had sensitivity of 90.5% and NPV of 95.9% but low specificity and PPV as 31.5% and 15.7%, respectively.<br />Conclusion:<br /> CCNA1 promoter methylation testing had very high specificity, likelihood ratio for the positive test and PPV (99.3%, 28.4 and 80.0, respectively). Therefore, CCNA1 promoter methylation test may be used in the HPV DNA positive cases to classify the urgency of colposcopy and the colposcopist should pay more attention to CCNA1 positive patients because of their higher chance to identify the significant lesions.

Retrospective analysis of cervical cancer and precancerous lesions in patients with atypical squamous cells of undetermined significance in China

Atypical squamous cells of undetermined significance (ASCUS) are the most common cytological abnormality of all smear test. No study has demonstrated the prevalence of cervical cancer or its precursor in Chinese patients with ASCUS. This study aims to investigate the prevalence of cervical intraepithelial neoplasia 1 or worse (CIN1+) and CIN3 or worse (CIN3+) in patients with ASCUS in China to provide insight into appropriate management for Chinese health care.In a retrospective cross-sectional study, patients who underwent liquid-based thin layer cytology and human papillomavirus (HPV) co-testing at the Peking Union Medical College Hospital between January 2014 and January 2017, and had ASCUS results on liquid-based thin layer cytology test and underwent follow-up and colposcopic biopsy were included. Age, HPV DNA test, and pathological outcomes were assessed.One hundred forty-four patients with ASCUS and positive HPV test results were included. In the 3-year follow-up, 23 (16.0%) patients had CIN1, 28 (19.4%) had CIN2, and 17 (11.8%) had CIN3 or carcinoma in situ. The risk of CIN3+ was significantly higher in those older than 60 years (42.8%, P = .005), whereas the CIN1+ prevalence displayed no significant difference between age groups. Both hybrid Capture II (HC II) value and cytopathological description of HPV infection showed no statistically significant correlation with CIN1+ or CIN3+.Patients with HPV-positive ASCUS who were older than 60 years had a significantly higher risk of CIN3+, and clinicians should pay more attention to them. Both HC II value and cytopathological description of HPV infection showed no significant correlation with CIN1+ or CIN3+.