Clinical Utility of Reflex Testing with Cancer Biomarkers to Improve Diagnostic Accuracy of Primary Human Papillomavirus Screening.

BACKGROUND: Human papillomavirus (HPV) testing is the cornerstone of cervical cancer screening, with outstanding sensitivity but only moderate specificity. We evaluated whether reflex testing for cancer biomarkers improves the sensitivity/specificity balance of screening. METHODS: Cervical samples from women in Cape Town, South Africa, ages 30-65 years, were collected and tested with Xpert HPV and with real-time PCR to detect mRNA for cyclin-dependent kinase inhibitor 2A (CDKN2A), topoisomerase 2 alpha (TOP2A), and Ki67 (MKi67). Women with histologically confirmed cervical intraepithelial neoplasia grade 2 or worse (CIN2+; 85 women without and 166 with HIV) and women with no cervical disease (331 without and 257 with HIV) were included. RESULTS: When used as reflex tests after a positive HPV result, biomarkers discriminated well between women with and without CIN2+. The inclusion of both CDKN2A and MKi67 had the best performance, with area under the curve (AUC) of 0.9171 and 0.8734 in women without and with HIV, respectively. Although excellent, these performance parameters did not improve on an approach utilizing only HPV testing with more stringent cycle threshold cutoffs and HPV genotype selection, which achieved AUC of 0.9059 and 0.8705 in women without and with HIV, respectively. CONCLUSIONS: Biomarkers can be used as triage after positive HPV results but do not outperform an approach utilizing higher viral load cutoffs on selected high-risk genotypes. IMPACT: A screening approach using HPV testing alone can be more easily implemented at the point of care.

Performance of Xpert HPV on Self-collected Vaginal Samples for Cervical Cancer Screening Among Women in South Africa.

OBJECTIVES: Self-sampling may increase access to cervical cancer screening in low-resource settings. Using Xpert HPV, we compared test performance of self- and clinician-collected samples in HIV-positive and HIV-negative women in South Africa. MATERIALS AND METHODS: Three hundred thirty HIV-positive and 375 HIV-negative women in the screening group and 202 HIV-negative and 200 HIV-positive women in the referral group, aged 30-65 years, participated in the study. All women self-collected a vaginal sample, and then, a cervical sample was collected by a clinician (both tested using Xpert HPV), followed by colposcopic examination and collection of histologic specimens. RESULTS: There was good agreement between self- and clinician-collected samples for detection of any high-risk human papillomavirus (HPV, κ = 0.72 [95% CI = 0.669-0.771]). Prevalence of HPV and sensitivity of the test to detect cervical intraepithelial neoplasia 2+ was similar in self- and clinician-collected samples. Specificity was lower in self-collected than in clinician-collected samples in both HIV-negative (self: 77.5% [95% CI = 72.8-81.8] vs clinician: 86.9% [95% CI = 82.9-90.2]) and HIV-positive (self: 44.0% [95% CI = 38.0-50.1] vs clinician: 59.7% [95% CI = 53.6-65.6]) women. Restricting the definition of screen-positive to 3 of 5 channels on HPV Xpert improved specificity in both HIV-negative (self: 83.2% [95% CI = 78.8-87.0] vs clinician: 89.7% [95% CI = 86.1-92.7]) and HIV-positive (self: 54.2% [95% CI = 48.1-60.2] vs clinician: 67.4% [95% CI = 61.5-72.9]) women. CONCLUSIONS: The self-collected sample had good agreement with the clinician-collected sample for the detection of HPV, and restricting the HPV types may improve the specificity in HIV-positive women.

mRNA Detection in Anal Cytology: A Feasible Approach for Anal Cancer Screening in Men Who Have Sex with Men Living With HIV.

There is growing interest in anal cancer screening strategies. However, cytological/molecular evaluation of anal samples is challenging. We aimed to determine the feasibility of detecting, in anal liquid-based cytologies, the expression of biomarkers involved in the cell cycle disturbance elicited by human papillomavirus (HPV). The accuracy of this approach in the identification of high-grade squamous intraepithelial lesions/anal intraepithelial neoplasia grade2-3 (HSIL/AIN2-3) was also evaluated. 215 anal cytologies from men having sex with men living with human immunodeficiency virus were evaluated. Patients showing concordant cytological and anoscopy-directed biopsy diagnosis were selected: 70 with negative cytology and HPV test, 70 with low-grade SIL (LSIL/AIN1) cytology and biopsy, and 75 with cytology and biopsy of HSIL/AIN2-3. CDKN2A/p16, MKI67 and TOP2A mRNA expression was analyzed. HPV detection was performed with Xpert HPV Assay (Cepheid, Sunnyvale, CA, USA). HSIL/AIN2-3 showed higher expression for the biomarkers than LSIL/AIN1 or negative samples. The specificity for HSIL/AIN2-3 detection for a sensitivity established at 70% was 44.7% (95%confidence interval [CI] 36.5-53.2) for TOP2A and MKI67 and 54.5% (95%CI 46.0-62.8%) for CDKN2A/p16. mRNA detection of cell biomarkers in anal liquid-based cytology is feasible. Further studies are warranted to confirm if strategies based on mRNA detection have any role in anal cancer screening.

mRNA biomarker detection in liquid-based cytology: a new approach in the prevention of cervical cancer.

Several high-risk human papillomavirus (HPV)-induced cell biomarkers have been proposed as possible candidates to identify patients harboring high-grade squamous intraepithelial lesions (HSILs) of the uterine cervix. We aimed to determine the feasibility of the detection of the mRNA of six biomarkers in cervical smear specimens obtained by liquid-based cytology and to evaluate whether this approach might be useful in the identification of patients with HSIL. One-hundred and twenty three women referred to colposcopy in the Hospital Clinic of Barcelona were included in the study. After a thorough study, including Pap test, high-risk HPV testing (Hybrid Capture 2 test), and colposcopy with directed biopsy and/or endocervical curettage, 48 patients were diagnosed with HSIL, whereas 75 were classified as negative (n=28), or harboring low-grade SIL (n=47). CDKN2A/p16, BIRC5, MMP9, TOP2A, MCM5, and MKI67 mRNA expression was analyzed by reverse transcription quantitative polymerase chain reaction in liquid-based cytology after the Pap test and Hybrid Capture 2 performance. The tissue expression of these biomarkers was analyzed by immunohistochemistry in the biopsy material. One-hundred and thirteen out of 123 (92%) liquid-based cytology yielded adequate material for mRNA analysis. TOP2A was the most sensitive (97%) biomarker for the detection of HSIL and CDKN2A/p16 the most specific (78%). The combination of TOP2A and CDKN2A/p16 showed a sensitivity of 96% (95% confidence interval (CI): 88-99) and a specificity of 71% (95% CI: 55-82). In the immunohistochemistry analysis, all biomarkers showed a high sensitivity but low specificity for HSIL, except CDKN2A/p16 which had a sensitivity of 100% and a specificity of 63%. The combination of TOP2A and CDKN2A/p16 showed a sensitivity of 100% (95% CI: 91-100) and a specificity of 43% (95% CI: 32-55). The detection of mRNA of cell biomarkers in liquid-based cytology material is feasible. The combination TOP2A and CDKN2A/p16 has a good balance between sensitivity and specificity for the detection of women with HSIL.