The LAST Project and the diagnostic bottom line

Meeting report: Considerations for trial design and endpoints in licensing therapeutic HPV16/18 vaccines to prevent cervical cancer

Cervical cancer is a major cause of morbidity and mortality globally with a disproportionate impact on women in low- and middle-income countries. In 2021, the World Health Organization (WHO) called for increased vaccination, screening, and treatment to eliminate cervical cancer. However, even with widespread rollout of human papillomavirus (HPV) prophylactic vaccines, millions of women who previously acquired HPV infections will remain at risk for progression to cancer for decades to come. The development and licensing of an affordable, accessible therapeutic HPV vaccine, designed to clear or control carcinogenic HPV and/or to induce regression precancer could significantly contribute to the elimination efforts, particularly benefiting those who missed out on the prophylactic vaccine. One barrier to development of such vaccines is clarity around the regulatory pathway for licensure. In Washington, D.C. on September 12-13, 2023, a meeting was convened to provide input and guidance on trial design with associated ethical and regulatory considerations. This report summarizes the discussion and conclusions from the meeting. Expert presentation topics included the current state of research, potential regulatory challenges, WHO preferred product characteristics, modeling results of impact of vaccine implementation, epidemiology and natural history of HPV infection, immune responses related to viral clearance and/or precancer regression including potential biomarkers, and ethical considerations. Panel discussions were held to explore specific trial design recommendations to support the licensure process for two vaccine indications: (1) treatment of prevalent HPV infection or (2) treatment of cervical precancers. Discussion covered inclusion/exclusion criteria, study endpoints, sample size and power, safety, study length, and additional data needed, which are reported here. Further research of HPV natural history is needed to address identified gaps in regulatory guidance, especially for therapeutic vaccines intended to treat existing HPV infections.

Evaluation of CD4+ cells infiltration as a prognostic factor in cervical intraepithelial neoplasia 2

OBJECTIVE

To identify candidate predictors for the prognosis of cervical intraepithelial neoplasia 2 (CIN2) lesions and evaluate the prognostic value of the local immune response.

METHODS

One hundred fifteen CIN2 patients were enrolled. The percentage of p16-, minichromosome maintenance complex component 2- or apolipoprotein B mRNA editing enzyme catalytic subunit 3G (APOBEC3G)-positive cells was determined immunohistochemically. Tumor-infiltrating lymphocytes (TILs) in intertumoral lesions were scored using an automated system. CIN3 disease progression and regression rates were estimated by the Kaplan-Meier method. A case-control study was conducted to screen CIN2 prognostic factors in 10 regression and 10 progression patients. Selected factors were examined in a cohort study to determine their prognostic value for CIN2.

RESULTS

Among all participants, the cumulative progression and regression rates at 60 months were 0.477 and 0.510, respectively. In the case-control study, p16- and APOBEC3G-positive cells were higher in the progression group (p=0.043, p=0.023). Additionally, CD4⁺ cell infiltration was enhanced in the regression group (p=0.023). The cohort study revealed a significantly increased progression rate in patients with elevated p16-positive cells (p<0.001), and increased CD4⁺ TIL infiltration was associated with better regression (p=0.011). Kaplan-Meier analysis according to human papillomavirus (HPV) positivity revealed a greater CIN3 development risk in HPV16-positive patients than in HPV16-negative cases. Finally, multivariate analysis identified HPV16 infection and CD4⁺ TIL infiltration as independent prognostic factors in CIN2 regression.

CONCLUSION

CD4⁺ TIL infiltration in intertumoral lesions was related with CIN2 regression. Our findings suggest CD4⁺ TIL infiltration may be useful for the triage of CIN2 patients.

Comparison of two sample collection devices for anal cytology in HIV-positive men who have sex with men: Cytology brush and Dacron swab

OBJECTIVE

HIV-positive men who have sex with men (MSM) are a vulnerable group for anal cancer (AC), a cancer with a well-described precursor lesion, which can be detected early in screening programs using anal liquid-based cytology (aLBC). We aim to compare two aLBC sample collection devices: cytology brush (CB) and Dacron swab (DS).

METHODS

Retrospective analysis of two consecutive study periods, the first using CB and the second DS. Participants underwent an aLBC, a human papillomavirus (HPV) DNA test and a high-resolution anoscopy (HRA), and a biopsy was performed for suspicious lesions. The sensitivity and specificity of aLBC, area under the receiver operating characteristic (ROC) curve (AUC), and concordance between cytology and HRA were assessed using Cohen's kappa coefficient.

RESULTS

A total of 239 participants were enrolled (CB group, 120; DS group, 119). aLBC was benign in 46% of samples, and high-grade squamous intraepithelial lesion (HSIL) was detected in 11.7%. Prevalence of biopsy-proven HSIL was 15.3%. No differences in cytological and histological results were observed between the groups. aLBC-HRA concordance was weak for benign results (CB group, k = 0.309; DS group, k = 0.350) as well as for HSIL (k = 0.321 and 0.387, respectively). Sensitivity and specificity were 100% and 51.4%, respectively, in the CB group and 88% and 54.3% in the DS group (AUC = 0.711 and 0.759, respectively, P-value = .514). Representation of the transformation zone (TZ) was adequate in 83.3% of samples in the CB group and 50.4% in the DS group (P-value <.001).

CONCLUSION

Our data suggest that both devices had similar accuracy to detect anal HSIL, although samples collected with CB are more likely to have an adequate TZ representation, the presence of which could be an indicator of sample quality.

Screening Women for Anal Cancers: Guidance for Health Care Professionals

Anal cancer is rare in the general population but is steadily increasing in incidence over the past decade especially in women. Identification and screening of women with high risk facilitates detection of anal precancer and early-stage cancer, improves survival, and potentially uses less invasive therapies compared with the conventional chemoradiation treatments used for advanced cancers. No recently published guidelines currently describe details about screening women for anal squamous cell cancer (ASCC). The available evidence supports the existence of groups of women with higher prevalence of ASCC (e.g., women with human immunodeficiency virus, immune suppression, or previous lower-genital high-grade lesion or cancer) who would likely benefit from screening with some combination of anal cytology and human papillomavirus testing. Additional research is needed to establish the cost-effectiveness and the influence of screening on ASCC mortality rates.

High-risk Human Papilloma Virus Testing Improves Diagnostic Performance to Predict Moderate- to High-grade Anal Intraepithelial Neoplasia in Human Immunodeficiency Virus-infected Men Who Have Sex With Men in Low-to-Absent Cytological Abnormalities

BACKGROUND

Screening methods for anal squamous intraepithelial lesions (SILs) are suboptimal. We aimed to determine the diagnostic performance of a composite endpoint comprising anal liquid-based cytology (aLBC) and high-risk human papillomavirus (HR-HPV) testing to predict histological high-grade SILs (hHSILs).

METHODS

From the SeVIHanal cohort, human immunodeficiency virus (HIV)-infected men who have sex with men (MSM) who had an aLBC with concomitant HR-HPV testing were included. hHSILs were determined by high-resolution anoscopy (HRA)-guided biopsy.

RESULTS

A total of 705 visits obtained from 426 patients were included. The prevalence of HR-HPV among aLBC results were 51.9% (133/215) normal, 87.9% (20/232) low-grade SILs (LSILs), and 90.9% (149/164) high-grade SILs; P (linear association) < .001. Low prevalence of hHSILs was only observed for the composite aLBC/HR-HPV testing endpoint "normal/noHR-HPV" (10%) and "LSIL/noHR-HPV" (4%). The prognostic values (95% confidence interval) for HR-HPV to predict hHSILs in normal cytology were positive predictive value (PPV), 29.3% (25.6%-33.3%); negative predictive value (NPV), 90.2% (82.8%-94.7%); sensitivity, 83% (69.2%-92.4%); and specificity, 44.1% (36.4%-51.9%). Corresponding figures for cytologic LSILs were PPV, 39.2% (37.4%-41.1%); NPV, 96.4% (78.9%-99.5%); sensitivity, 98.8% (93.3%-99.9%); and specificity, 17.9% (12.1%-24.9%). A positive interaction and a synergistic effect for the composite endpoint were observed (relative excess risk = 1.50, attributable proportion of histological results to interaction = 0.17, synergy index = 1.24).

CONCLUSIONS

HRA should not be indicated in the setting of LSILs/noHR-HPV following aLBC-based screening. In contrast, HIV-infected MSM with normal aLBC/HR-HPV infection should be considered for HRA.

CLINICAL TRIALS REGISTRATION

NCT03713229.

High-resolution anoscopy in HIV-infected men: Assessment of the learning curve and factors that improve the performance

Objective

To determine the required learning time for high-resolution anoscopy (HRA)-guided biopsy to detect histological high-risk squamous intraepithelial lesions (hHSIL) and to identify factors that impact on the training process.

Methods

All HIV-infected, screening-naïve men-who-have-sex-with-men who underwent HRA conducted by one single observer from 2010 to 2017 in a Spanish HIV-outpatient clinic were analysed.

Results

Eighty-five (14.7%) of the 581 patients included presented hHSIL. The factors associated with the capacity to detect hHSIL [adjusted odds ratio (aOR), 95% confidence interval (95%CI)] were the presence of cytological HSIL (3.04, 1.78–5.21; p < 0.001), infection with high-risk human papilloma virus (HR-HPV) (2.89, 1.38–6.05; p = 0.005), the number of biopsies taken/HRA (aOR: 1.28, 1.07–1.52; p = 0.006) and tobacco smoking (1.75; 1.12–2.73; p = 0.014). Two events independently augmented the detection rate of hHSIL: one single experienced pathologist interpreted biopsies after 409 HRA (2.80, 1.74–4.48; p = 0.035) and the anoscopist underwent an additional training after 536 HRA (2.57, 1.07–6.16; p = 0.035). A learning process could be observed throughout the whole study with stable HR-HPV prevalence.

Conclusion

The data support the growing evidence that the proposed training volume of 50–200 performances is underestimated. Extensive training of both anoscopist and pathologist is warranted and the development of tools to support the diagnostic performance may be considered.

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HRA-guided biopsy to detect histological HSIL requires a long learning period.

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581 HIV-infected men who have sex with men underwent HRA conducted by one observer.

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Throughout the whole study period, a learning process was noted with stable HR-HPV.

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The widely proposed training volume of 50–200 performances is probably underestimated.

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Extensive training of anoscopist/pathologist, and possibly AI tools, are warranted.

HPV-Associated Anal Cancer in the HIV/AIDS Patient

The prevalence of anal human papillomavirus (HPV) infection and anal high-grade squamous intraepithelial lesion (HSIL) remain high among HIV-infected individuals on effective antiretroviral therapy (ART). The incidence of HPV-related anal cancers has continued to increase since the introduction of ART. Therefore, ART may confer only limited benefit with respect to reducing the risk of anal HSIL and cancer. Efforts are in progress to define the efficacy of secondary prevention programs for prevention of anal cancer. In the modern ART era, anal cancer recurrence and survival outcomes are similar in HIV-infected and HIV-uninfected patients, but HIV-infected patients may experience more toxicities. This article reviews the current literature on HPV-associated anal cancer in the HIV-infected population, including epidemiology, screening, clinical characteristics, and treatment outcomes.

Self-sampling with HPV mRNA analyses from vagina and urine compared with cervical samples

BACKGROUND

In order to increase coverage in the organized cervical screening program, self-sampling with HPV analyses has been suggested.

OBJECTIVES

The aim was to compare human papillomavirus (HPV) mRNA detection in vaginal and urine self-collected samples with clinician-taken cervical samples and the corresponding clinician-taken histological specimens.

STUDY DESIGN

Self-collected vaginal, urine and clinician-taken cervical samples were analyzed from 209 women with the Aptima mRNA assay (Hologic Inc, MA, USA). Cervical cytology, colposcopy, biopsy and/or the loop electrosurgical excision procedure (LEEP) were performed in every examination.

RESULTS

The sensitivity of the HPV mRNA test in detecting high-grade squamous intraepithelial lesions (HSIL)/adenocarcinoma in situ (AIS)/cancer cases was as follows: for the vaginal self-samples 85.5% (95% CI; 75.0-92.8), the urinary samples 44.8% (95% CI; 32.6-57.4), and for routine cytology 81.7% (95% CI; 70.7-89.9). For the clinician-taken cervical HPV samples the sensitivity of the HPV mRNA test in detecting HSIL/AIS/cancer was 100.0% (95% CI; 94.9-100.0). The specificity of the HPV mRNA was similar for the clinician-taken cervical HPV samples and the self-samples: 49.0% vs. 48.1%. The urinary HPV samples had a specificity of 61.9% and cytology had a specificity of 93.3%.

CONCLUSION

The sensitivity of the Aptima HPV mRNA test in detecting HSIL/AIS/cancer from vaginal self-samples was similar to that of routine cytology. The Aptima HPV mRNA vaginal self-sampling analysis may serve as a complement in screening programs.