Birgit Engesæter

The Predictive Impact of HPV Genotypes, Tumor Suppressors and Local Immune Response in the Regression of Cervical Intraepithelial Neoplasia 2-3: A Prospective Population-Based Cohort Study

Cervical intraepithelial neoplasia (CIN) is caused by human papillomavirus (HPV); however, factors such as HPV genotype and individual immune response may also contribute to its development. The loop electrosurgical excision procedure (LEEP) is a treatment for high-grade cervical intraepithelial neoplasia (CIN), as approximately 30% of these cases may progress to cancer. However, 20–40% of cases will regress spontaneously. HPV16 infection constitutes the highest risk for progression to cervical cancer and a lower probability of regression. Knowledge regarding the regression of lesions caused by other high-risk genotypes alone or in association with biomarker expression and lesion length has been limited. In the present study, the regression rates of high-grade squamous intraepithelial lesions were calculated. Twenty-one percent of the 161 women diagnosed with CIN2-3 on colposcopy-directed biopsies exhibited regression (defined as CIN1 or less) in the subsequent cone excisions. The mean interval between biopsy and treatment was 113 days (range of 71–171). High-grade lesions of the squamous epithelium caused by HPV16, together with lesions caused by HPV31, 52 and 58, showed significantly lower regression rates (HR 0.54, 0.22–0.75; low-regression group) than lesions caused by HPV18, 33, 35, 39, and 45 (HR 2.85, 1.54–5.28; high-regression group). A multivariate analysis of HPV genotypes, epithelial expressions of pRb and p53, immune cell proportions in the stroma (CD4/CD25 and CD4/CD8), and lesion lengths correctly predicted regression in 78% (Harrell’s C). A Harrell’s C value of 82% for the low-regression group indicates that different HPV genotypes or groups, together with divergent patterns of tumor suppressors, immune cells, and lesion size, can give prognostic information regarding the outcome of CIN2-3.

Randomized Implementation of a Primary Human Papillomavirus Testing–based Cervical Cancer Screening Protocol for Women 34 to 69 Years in Norway

Abstract Background: Cervical cancer screening programs are facing a programmatic shift where screening protocol based on human papillomavirus testing (HPV-Screening protocol) is replacing the liquid-based cytology (LBC-Screening protocol). For safe technology transfer within the nationwide screening programme in Norway, HPV-Screening protocol was implemented randomized to compare the real-world effectiveness of HPV-Screening protocol and LBC-Screening protocol at the first screening round. Methods: Among 302,295 women ages 34 to 69 years scheduled to attend screening from February 2015 to June 2017, 157,447 attended. A total of 77,207 were randomly allocated to the HPV-Screening protocol and 80,240 were allocated to the LBC-Screening protocol. All women were followed up for 18 months. Results: The HPV-Screening protocol resulted in a relative increase of 60% in the detection of cervical intraepithelial neoplasia (CIN) grade 2 or worse [risk ratio (RR) = 1.6, 95% confidence interval (CI) = 1.5–1.7], 40% in CIN grade 3 or worse (RR = 1.4, 95% CI = 1.3–1.6), 40% in cancer (RR = 1.4, 95% CI = 1.0–2.1), and 60% in colposcopy referrals (RR = 1.6, 95% CI = 1.5–1.6) compared with LBC-Screening. The performance of both protocols was age dependent, being more effective in women ages under 50 years. Conclusions: The HPV-Screening protocol was well accepted by women in Norway and detected more CIN2, CIN3, and cancers compared with the LBC-Screening protocol. Impact: A randomized implementation of the HPV-Screening protocol with real-world assessment enabled a gradual, quality assured, and safe technology transition. HPV-based screening protocol may further be improved by using HPV genotyping and age-specific referral algorithms.

Cost‐effectiveness of primary human papillomavirus triage approaches among vaccinated women in Norway: A model‐based analysis

AbstractAs Norway considers revising triage approaches following their first adolescent cohort with human papillomavirus (HPV) vaccination entering the cervical cancer screening program, we analyzed the health impact and cost‐effectiveness of alternative primary HPV triage approaches for women initiating cervical cancer screening in 2023. We used a multimodeling approach that captured HPV transmission and cervical carcinogenesis to evaluate the health benefits, harms and cost‐effectiveness of alternative extended genotyping and age‐based triage strategies under five‐yearly primary HPV testing (including the status‐quo screening strategy in Norway) for women born in 1998 (ie, age 25 in 2023). We examined 35 strategies that varied alternative groupings of high‐risk HPV genotypes (“high‐risk” genotypes; “medium‐risk” genotypes or “intermediate‐risk” genotypes), number and types of HPV included in each group, management of HPV‐positive women to direct colposcopy or active surveillance, wait time for re‐testing and age at which the HPV triage algorithm switched from less to more intensive strategies. Given the range of benchmarks for severity‐specific cost‐effectiveness thresholds in Norway, we found that the preferred strategy for vaccinated women aged 25 years in 2023 involved an age‐based switch from a less to more intensive follow‐up algorithm at age 30 or 35 years with HPV‐16/18 genotypes in the “high‐risk” group. The two potentially cost‐effective strategies could reduce the number of colposcopies compared to current guidelines and simultaneously improve health benefits. Using age to guide primary HPV triage, paired with selective HPV genotype and follow‐up time for re‐testing, could improve both the cervical cancer program effectiveness and efficiency.