The added value of digital imaging to reflex cytology for triage of high-risk human papillomavirus positive self-sampled material in cervical cancer screening: A prospective cohort study.

OBJECTIVE: Cytology performed directly on hrHPV-positive self-samples (reflex cytology) is feasible and for women with abnormal cytology, an additional cytology test at the general practitioner could be omitted. The aim of this study is to assess the added value of digital imaging (ThinPrep® Imaging System) on the clinical utility of reflex cytology by reducing screening error. DESIGN: A secondary analysis of a prospective cohort study. SETTING: One of five Dutch screening laboratories. POPULATION: Women tested hrHPV-positive on self-samples between December 2018 and August 2019. METHODS: Self-samples were used for reflex cytology with and without digital imaging. The follow-up data (cytological and histological results within 1 year of follow-up) were obtained through the Dutch Pathology Registry (PALGA). MAIN OUTCOME MEASURES: Test performance of the reflex cytology was determined by comparing it with physician-collected follow-up results. RESULTS: The sensitivity for detecting abnormal cells by reflex cytology on self-samples increased significantly from 26.3% (42/160; 95% confidence interval [CI] 19.6-33.8) without digital imaging to 35.4% (56/158; 95% CI 28-43.4) with digital imaging (P < 0.05) without compromising specificity. Importantly, 41.7% of women with ≥CIN2 (35/84) and 45.6% with ≥CIN3 (26/57) were detected by reflex cytology with digital imaging on hrHPV-positive self-samples. CONCLUSION: Digital imaging is of added value to reflex cytology on hrHPV-positive self-samples with a 9% increase in sensitivity. If reflex cytology on self-samples analysed with digital imaging had been implemented in the screening programme, 35.4% of the hrHPV-positive women with abnormal cytology on additional physician-collected samples could have been referred directly for colposcopy.

Targeted RNA next generation sequencing analysis of cervical smears can predict the presence of hrHPV-induced cervical lesions.

BACKGROUND: Because most cervical cancers are caused by high-risk human papillomaviruses (hrHPVs), cervical cancer prevention programs increasingly employ hrHPV testing as a primary test. The high sensitivity of HPV tests is accompanied by low specificity, resulting in high rates of overdiagnosis and overtreatment. Targeted circular probe-based RNA next generation sequencing (ciRNAseq) allows for the quantitative detection of RNAs of interest with high sequencing depth. Here, we examined the potential of ciRNAseq-testing on cervical scrapes to identify hrHPV-positive women at risk of having or developing high-grade cervical intraepithelial neoplasia (CIN). METHODS: We performed ciRNAseq on 610 cervical scrapes from the Dutch cervical cancer screening program to detect gene expression from 15 hrHPV genotypes and from 429 human genes. Differentially expressed hrHPV- and host genes in scrapes from women with outcome "no CIN" or "CIN2+" were identified and a model was built to distinguish these groups. RESULTS: Apart from increasing percentages of hrHPV oncogene expression from "no CIN" to high-grade cytology/histology, we identified genes involved in cell cycle regulation, tyrosine kinase signaling pathways, immune suppression, and DNA repair being expressed at significantly higher levels in scrapes with high-grade cytology and histology. Machine learning using random forest on all the expression data resulted in a model that detected 'no CIN' versus CIN2+ in an independent data set with sensitivity and specificity of respectively 85 ± 8% and 72 ± 13%. CONCLUSIONS: CiRNAseq on exfoliated cells in cervical scrapes measures hrHPV-(onco)gene expression and host gene expression in one single assay and in the process identifies HPV genotype. By combining these data and applying machine learning protocols, the risk of CIN can be calculated. Because ciRNAseq can be performed in high-throughput, making it cost-effective, it can be a promising screening technology to stratify women at risk of CIN2+. Further increasing specificity by model improvement in larger cohorts is warranted.

Novel high-resolution targeted sequencing of the cervicovaginal microbiome.

BACKGROUND: The cervicovaginal microbiome (CVM) plays a significant role in women's cervical health and disease. Microbial alterations at the species level and characteristic community state types (CST) have been associated with acquisition and persistence of high-risk human papillomavirus (hrHPV) infections that may result in progression of cervical lesions to malignancy. Current sequencing methods, especially most commonly used multiplex 16S rRNA gene sequencing, struggle to fully clarify these changes because they generally fail to provide sufficient taxonomic resolution to adequately perform species-level associative studies. To improve CVM species designation, we designed a novel sequencing tool targeting microbes at the species taxonomic rank and examined its potential for profiling the CVM. RESULTS: We introduce an accessible and practical circular probe-based RNA sequencing (CiRNAseq) technology with the potential to profile and quantify the CVM. In vitro and in silico validations demonstrate that CiRNAseq can distinctively detect species in a mock mixed microbial environment, with the output data reflecting its ability to estimate microbes' abundance. Moreover, compared to 16S rRNA gene sequencing, CiRNAseq provides equivalent results but with improved sequencing sensitivity. Analyses of a cohort of cervical smears from hrHPV-negative women versus hrHPV-positive women with high-grade cervical intraepithelial neoplasia confirmed known differences in CST occurring in the CVM of women with hrHPV-induced lesions. The technique also revealed variations in microbial diversity and abundance in the CVM of hrHPV-positive women when compared to hrHPV-negative women. CONCLUSIONS: CiRNAseq is a promising tool for studying the interplay between the CVM and hrHPV in cervical carcinogenesis. This technology could provide a better understanding of cervicovaginal CST and microbial species during health and disease, prompting the discovery of biomarkers, additional to hrHPV, that can help detect high-grade cervical lesions.

Cervical intraepithelial neoplasia and the risk of spontaneous preterm birth: A Dutch population-based cohort study with 45,259 pregnancy outcomes.

BACKGROUND: Excisional procedures of cervical intraepithelial neoplasia (CIN) may increase the risk of preterm birth. It is unknown whether this increased risk is due to the excision procedure itself, to the underlying CIN, or to secondary risk factors that are associated with both preterm birth and CIN. The aim of this study is to assess the risk of spontaneous preterm birth in women with treated and untreated CIN and examine possible associations by making a distinction between the excised volume of cervical tissue and having cervical disease. METHODS AND FINDINGS: This Dutch population-based observational cohort study identified women aged 29 to 41 years with CIN between 2005 and 2015 from the Dutch pathology registry (PALGA) and frequency matched them with a control group without any cervical abnormality based on age at and year of pathology outcome (i.e., CIN or normal cytology) and urbanization (<100,000 inhabitants or ≥100,000 inhabitants). All their 45,259 subsequent singleton pregnancies with a gestational age ≥16 weeks between 2010 and 2017 were identified from the Dutch perinatal database (Perined). Nineteen potential confounders for preterm birth were identified. Adjusted odds ratios (ORs) were calculated for preterm birth comparing the 3 different groups of women: (1) women without CIN diagnosis; (2) women with untreated CIN; and (3) women with treated CIN prior to each childbirth. In total, 29,907, 5,940, and 9,412 pregnancies were included in the control, untreated CIN, and treated CIN group, respectively. The control group showed a 4.8% (1,002/20,969) proportion of spontaneous preterm birth, which increased to 6.9% (271/3,940) in the untreated CIN group, 9.5% (600/6,315) in the treated CIN group, and 15.6% (50/321) in the group with multiple treatments. Women with untreated CIN had a 1.38 times greater odds of preterm birth compared to women without CIN (95% confidence interval (CI) 1.19 to 1.60; P < 0.001). For women with treated CIN, these odds 2.07 times increased compared to the control group (95% CI 1.85 to 2.33; P < 0.001). Treated women had a 1.51 times increased odds of preterm birth compared to women with untreated CIN (95% CI 1.29 to 1.76; P < 0.001). Independent from cervical disease, a volume excised from the cervix of 0.5 to 0.9 cc increased the odds of preterm birth 2.20 times (37/379 versus 1,002/20,969; 95% CI 1.52 to 3.20; P < 0.001). These odds further increased 3.13 times and 5.93 times for women with an excised volume of 4 to 8.9 cc (90/724 versus 1,002/20,969; 95% CI 2.44 to 4.01; P < 0.001) and ≥9 cc (30/139 versus 1,002/20,969; 95% CI 3.86 to 9.13; P < 0.001), respectively. Limitations of the study include the retrospective nature, lack of sufficient information to calculate odds of preterm birth <24 weeks, and that the excised volume could only be calculated for a select group of women. CONCLUSIONS: In this study, we observed a strong correlation between preterm birth and a volume of ≥0.5 cc excised cervical tissue, regardless of the severity of CIN. Caution should be taken when performing excisional treatment in women of reproductive age as well as prudence in case of multiple biopsies. Fertile women with a history of performing multiple biopsies or excisional treatment for CIN may benefit from close surveillance during pregnancy.

The Natural History of Cervical Intraepithelial Neoplasia Grades 1, 2, and 3: A Systematic Review and Meta-analysis.

OBJECTIVE: The aim of the study was to obtain an updated overview of regression, persistence, and progression rates of conservatively managed cervical intraepithelial neoplasia grade 1 (CIN 1)/CIN 2/CIN 3. METHODS: Data sources were MEDLINE, Embase, and Cochrane (January 1, 1973-April 14, 2020). Two reviewers extracted data and assessed risk of bias. To estimate outcome rates, we pooled proportions of the individual study results using random-effects meta-analysis, resulting in point estimates and corresponding 95% CIs. Heterogeneity was quantified by the I2 and τ2 measures. RESULTS: Eighty-nine studies were included, 63 studies on CIN 1 (n = 6,080-8,767), 42 on CIN 2 (n = 2,909-3,830), and 7 on CIN 3 (n = 245-351). The overall regression, persistence, and progression to CIN 2 or worse and CIN 3 or worse rates for women with conservatively managed CIN 1 were 60% (95% CI = 55-65, I2 = 92%), 25% (95% CI = 20-30, I2 = 94%), 11% (95% CI = 8-13, I2 = 89%), and 2% (95% CI = 1-3, I2 = 82%), respectively. The overall regression, persistence, and progression rates for CIN 2 were 55% (95% CI = 50-60, I2 = 85%), 23% (95% CI = 19-28, I2 = 83%), and 19% (95% CI = 15-23, I2 = 88%), respectively. Finally, for CIN 3, these were 28% (95% CI = 17-41, I2 = 68%), 67% (95% CI = 36-91, I2 = 84%), and 2% (95% CI = 0-25, I2 = 95%), respectively. Cervical intraepithelial neoplasia grade 2 regression was significantly higher in women 30 years or younger and high-risk human papillomavirus-negative women (66%, 95% CI = 62-70, I2 = 76%; 94%, 95% CI = 84-99, I2 = 60%). Only 2/7,180 (0.03%) and 10/3,037 (0.3%) of the CIN 1 and CIN 2 cases progressed to cervical cancer. CONCLUSIONS: Most CIN 1/CIN 2 will regress spontaneously in less than 24 months, with the highest rates in high-risk human papillomavirus-negative and young women, whereas progression to cancer is less than 0.5%. Conservative management should be considered, especially in fertile women and with expected high compliance. Given the heterogeneity in regression rates of high-grade histology, this should be classified as CIN 2 or CIN 3 to guide management.

Benefit and burden in the Dutch cytology-based vs high-risk human papillomavirus-based cervical cancer screening program.

BACKGROUND: In 2017, the Dutch cervical cancer screening program had replaced the primary cytology-based screening with primary high-risk human papillomavirus-based screening, including the opportunity to participate through self-sampling. Evaluation and balancing benefit (detection of high-grade cervical intraepithelial neoplasia) and burden of screening (unnecessary referrals, invasive diagnostics, and overtreatment) is needed. OBJECTIVE: This study aimed to compare the referral rates, detection of high-grade cervical intraepithelial neoplasia, overdiagnosis, and overtreatment in the new high-risk human papillomavirus-based screening program, including physician-sampled and self-sampled material, with the previous cytology-based screening program in the Netherlands. STUDY DESIGN: A retrospective cohort study was conducted within the Dutch population-based cervical cancer screening program. Screenees with referrals for colposcopy between 2014 and 2015 (cytology-based screening) and 2017 and 2018 (high-risk human papillomavirus-based screening) were included. Data were retrieved from the Dutch Pathology Registry (PALGA) and compared between the 2 screening programs. The main outcome measures were referral rate, detection of high-grade cervical intraepithelial neoplasia or worse, overdiagnosis (cervical intraepithelial neoplasia grade 1 or less in the histologic specimen), and overtreatment (cervical intraepithelial neoplasia grade 1 or less in the treatment specimen). RESULTS: Of the women included in the study, 19,109 received cytology-based screening, and 26,171 received high-risk human papillomavirus-based screening. Referral rates increased from 2.5% in cytology-based screening to 4.2% in high-risk human papillomavirus-based screening (+70.2%). Detection rates increased to 46.2% for cervical intraepithelial neoplasia grade 2 or worse, 32.2% for cervical intraepithelial neoplasia grade 3 or worse, and 31.0% for cervical cancer, and overdiagnosis increased to 143.4% with high-risk human papillomavirus-based screening. Overtreatment rates were similar in both screening periods. The positive predictive value of referral for detection of cervical intraepithelial neoplasia grade 2 or worse in high-risk human papillomavirus-based screening was 34.6% compared with 40.2% in cytology-based screening. Women screened through self-sampling were at higher risk of cervical intraepithelial neoplasia grade 2 or worse detection (odds ratio, 1.38; 95% confidence interval, 1.20-1.59) and receiving treatment (odds ratio, 1.31; 95% confidence interval, 1.16-1.48) than those screened through physician-sampling. CONCLUSION: Compared with cytology-based screening, high-risk human papillomavirus-based screening increases detection of high-grade cervical intraepithelial neoplasia, with 462 more cervical intraepithelial neoplasia grade 2 or worse cases per 100,000 women but at the expense of 850 more cases per 100,000 women with invasive diagnostics indicating cervical intraepithelial neoplasia grade 1 or less.

The risk of cervical cancer after cervical intraepithelial neoplasia grade 3: A population-based cohort study with 80,442 women.

OBJECTIVE: To estimate the risk of cervical cancer in women with a history of cervical intraepithelial neoplasia (CIN) grade 3 and to review the compliance with post-treatment follow-up. METHODS: A population-based retrospective cohort study including 80,442 women with a median follow-up of 15.8 years, and 1,278,297 person years. Women with CIN3 between 1990 and 2010 were identified from the Dutch Pathology Registry (PALGA) and linked to the general female population from the Netherlands Cancer Registry. Cases of recurrent CIN3 and cervical cancer, defined as occurrence minimally two years post-treatment, were identified until 2016. Standardized incidence ratios (SIRs) were calculated for the risk of cervical cancer. RESULTS: 1554 women (1.9%) developed recurrent CIN3 and 397 women (0.5%) cervical cancer. Women with CIN3 were associated with a twofold increased risk of cervical cancer (SIR 2.29; 95%CI 2.07-2.52) compared with the general female population. Women aged ≥50 years during CIN3 diagnosis had a sevenfold and women with recurrent CIN3 a ninefold increased risk of developing cervical cancer. The increased risk up to 20 years of follow-up seems to be mostly attributable to ageing. 37.0% of women who developed cervical cancer after CIN3 did not complete the advised post-treatment follow-up. CONCLUSIONS: Women with CIN3 have a long-lasting twofold increased risk of developing cervical cancer, even when they complete the post-treatment follow-up and adhere to the regular screening program. This risk increases with CIN3 diagnosis at older age, further ageing during follow-up and in women with recurrent CIN3. Studies on optimizing follow-up strategies are warranted.

RNA-based high-risk HPV genotyping and identification of high-risk HPV transcriptional activity in cervical tissues.

Nearly all cervical cancers are initiated by a persistent infection with one of the high-risk human papillomaviruses (high-risk HPV). High-risk HPV DNA testing is highly sensitive but cannot distinguish between active, productive infections and dormant infections or merely deposited virus. A solution for this shortcoming may be the detection of transcriptional activity of viral oncogenes instead of mere presence of high-risk HPVs. In this study, fresh-frozen cervical tissues (n = 22) were subjected to high-risk HPV DNA detection using the line probe assay and to targeted RNA next-generation sequencing using single-molecule molecular inversion probes. Targeted RNA sequencing was applied for (1) RNA-based genotyping of high-risk HPV, giving information on specific HPV-subtype (2) discrimination of E2, E6, and E7 transcripts and (3) discovery of possible non-HPV cancer biomarkers. Data were analyzed using computational biology. Targeted RNA sequencing enabled reliable genotyping of high-risk HPV subtypes and allowed quantitative detection of E2, E6, and E7 viral gene expression, thereby discriminating cervical lesions from normal cervical tissues. Moreover, targeted RNA sequencing identified possible cervical cancer biomarkers other than high-risk HPV. Interestingly, targeted RNA sequencing also provided high-quality transcription profiles from cervical scrape samples, even after 1 week of dry storage or storage in Preservcyt fixative. This proof of concept study shows that targeted RNA sequencing can be used for high-risk HPV genotyping and simultaneous detection of high-risk HPV gene activity. Future studies are warranted to investigate the potential of targeted RNA sequencing for risk assessment for the development of cervical lesions, based on molecular analysis of cervical scrapes.

Oral contraceptive and intrauterine device use and the risk of cervical intraepithelial neoplasia grade III or worse: a population-based study.

OBJECTIVE: Hormonal contraceptive use has been associated with the development of cervical cancer, although inconsistent results are reported on the association with intrauterine device (IUD) use. The aim of this study was to evaluate the association between the type of contraceptive use and the development of cervical intraepithelial neoplasia grade III or worse (CIN3+). METHODS: A retrospective population-based cohort study including women aged 29-44 years attending the cervical cancer screening program with normal cytology between 2005 and 2009 identified from the Dutch Pathology Registry. Subgroups with at least 5 years registered use of an oral contraceptive (OC) or IUD were compared with non-users. Risk ratios of CIN3+ were estimated per contraceptive type. RESULTS: 702,037 women were included with a median follow-up of 9.7 years, of which 6705 (0.96%) and 559 (0.08%) women developed CIN3 and cervical cancer, respectively. IUD use was associated with an increased risk of developing CIN3+ (risk ratio (RR) 1.51, 95% confidence interval (CI) 1.32-1.74), and OC use was associated with an increased risk of developing CIN3+ (RR 2.77, 95%CI 2.65-3.00) and cervical cancer (RR 2.06, 95%CI 1.52-2.79). The risk of developing CIN3+ and cervical cancer was higher for OC users compared with IUD users (RR 1.83, 95%CI 1.60-2.09 and RR 1.70, 95%CI 1.00-2.90, respectively). CONCLUSIONS: Both OC use and IUD use were associated with an increased risk of developing CIN3+. However, for women with a contraceptive wish, an IUD seems safer than an OC as the risk of developing CIN3+ and cervical cancer was higher for OC users.

Clinical practice variation and overtreatment risk in women with abnormal cervical cytology in the Netherlands: two-step versus see-and-treat approach.

BACKGROUND: Only a few small studies have compared the 2-step method (biopsy followed by treatment) with a see-and-treat (immediate treatment) approach in women both low-grade or high-grade referral cytology. The clinical practice variation in the Netherlands has not been reviewed before. OBJECTIVES: To determine overtreatment rates in the 2-step versus see-and-treat approach in women referred for colposcopy because of abnormal cytology results, and to evaluate clinical practice variation in the Netherlands. MATERIALS AND METHODS: This was a population-based retrospective cohort study including 36,581 women with a histologic result of the cervix identified from the Dutch Pathology Registry (PALGA) between 2016 and 2017. Odds ratios for overtreatment, defined primarily as cervical intraepithelial neoplasia grade 1 or less, were determined for the 2-step and see-and-treat approach in relation to age, high-risk human papillomavirus status, and referral cytology. RESULTS: Of the included women 10,713 women (29.3%) received the 2-step method; 6,851 women (18.7%) underwent see-and-treat; and 19,017 women (52.0%) received conservative management after colposcopy with histologic assessment with cytologic follow-up or another type of treatment. Despite the existence of a national guideline advising see-and-treat only in case of suspected high-grade disease in women who have completed their childbearing, there is a wide practice variation between the 2 strategies in the Netherlands, with 7.0-88.3% of the women receiving see-and-treat per laboratory. The median time between cytology and treatment was 1-2 months (range, 0-12 months) in women receiving see-and-treat and the 2-step method, respectively. A total of 4119 women (23.5%) were overtreated, with older women, high-risk human papillomavirus-negative women, and women with low-grade cytology results being more likely to be overtreated. Women with low-grade cytology results and see-and-treat were associated with a higher overtreatment rate than women receiving the 2-step method (65.0% [1414 of 2174] versus 32.1% [1161 of 3613], respectively; odds ratio, 3.34; 95% confidence interval, 2.92-3.82). However, in women with high-grade cytology results, see-and-treat was inversely associated with overtreatment (11.3% [529 of 4677] versus 14.3% [1015 of 7100], respectively; odds ratio, 0.68; 95% confidence interval, 0.58-0.81). CONCLUSION: A see-and-treat approach is justified only in women with high-grade cytology results who have completed their childbearing. There is a wide practice variation between the 2 strategies in the Netherlands, and gynecologists should adhere to the guideline to prevent overtreatment.

The relative risk of noncervical high-risk human papillomavirus-related (pre)malignancies after recurrent cervical intraepithelial neoplasia grade 3: A population-based study.

Women with cervical intraepithelial neoplasia grade 3 (CIN3) have a long-lasting increased risk for noncervical high-risk human papillomavirus (hrHPV)-related (pre)malignancies. The aim of our study was to estimate this risk in women with recurrent CIN3 compared to women without a history of CIN3 and women with a single episode of CIN3. Women with a CIN3 diagnosis between 1990 and 2010 were obtained from the Dutch Pathology Registry (PALGA) and matched with a control group of women without CIN3. Analysis has been conducted in a subset of women with recurrent CIN3, defined as reoccurrence minimally 2 years post-treatment. Cases of noncervical hrHPV-related (pre)malignancies of the anus, vulva, vagina and oropharynx were identified until 2015 and incidence rate ratios (IRRs) were estimated. Then, 1,797 women with recurrent CIN3 were included with a median age of 34 years (range 18-76) and 31,594 person-years of follow-up. Women with recurrent CIN3 had an increased risk of developing noncervical hrHPV-related (pre)malignancies compared to women without CIN3 with an IRR of 25.96 (95%CI 6.32-106.58). The IRR was 2.48 (95% CI 1.87-3.30) compared to women with a single episode of CIN3. Studies on posttreatment follow-up and prophylactic hrHPV vaccination are warranted.

Post-Colposcopy Management and Progression Predictors of Biopsy-Proven CIN1 in Women Under 25 Years.

OBJECTIVE: The post-colposcopy management and outcome of cervical intraepithelial neoplasia grade 1 (CIN1) in women under 25 years of age was reviewed, and potential predictors for progression were identified. METHODS: Women under 25 with biopsy-proven CIN1 between January 1, 2010, and December 31, 2012 who were seen in the colposcopy clinic at the Queen Elizabeth II Hospital in Halifax, Nova Scotia were retrospectively reviewed. The regression, persistence, and progression rates of CIN1 were evaluated, and the relevant behavioural and biologic factors were reviewed. RESULTS: Of the 326 women with a biopsy-proven CIN1, 234 (71.8%) women returned to the regular screening program, and 92 women remained in the colposcopy clinic during follow-up, with a median follow-up time of 26 months. Sixty-two percent of the women had no cervical abnormality, 23.6% of the women had persistent CIN1, and 14.4% of the women showed progression. Eight percent showed progression to CIN2 with a median time of 13 months, whereas 6.4% showed progression to CIN3+ within a median time of 17.5 months. The extent of the lesion (hazard ratio 2.33; 95% CI 1.17-4.64, P = 0.02) and the Pap test result at the initial visit (hazard ratio 2.16; 95% CI 1.22-3.82, P = 0.008) were significantly associated with progression to CIN2+. CONCLUSION: On the basis of the 6% risk of CIN3+ and the median time to progression of 17.5 months, follow-up with cytology at 12 months seems acceptable. The extent of the lesion and the Pap test result at the initial visit were identified as risk factors for progression of CIN1.

Justifying conservative management of CIN2 in women younger than 25 years - A population-based study.

OBJECTIVE: In 2012, the joint clinical practice guideline from the Society of Obstetricians and Gynaecologists of Canada (SOGC) changed from immediate treatment to a more conservative management of Cervical Intraepithelial Neoplasia (CIN) grade 2 in young women. In this study, the outcomes before and after this management change were reviewed in Nova Scotia, Canada. METHODS: A retrospective population-based cohort study was performed among women younger than 25 years with biopsy-proven CIN2, who were diagnosed in one of the colposcopy clinics in Nova Scotia between 2010 and 2014. Regression and progression rates were compared pre- and post-guideline changes. RESULTS: Of the 636 women included in the study, 286 women were diagnosed with CIN2 before and 350 women after the management in Nova Scotia was changed. After implementation of the 2012 guidelines patients were more likely to receive conservative management (78.6% versus 44.1%; p < 0.001); which differs from the patients who underwent treatment during follow-up prior to the change in guidelines (73.4% versus 38.9%; p < 0.001). Regression occurred in 73.1% of all women, but women seen in the post-guideline change period had a higher regression rate and lower progression rate (p < 0.05). Histologic results from treatment specimen did not show a significant difference in low-grade or high-grade lesions before or after the guideline had been changed (p = 0.59). CONCLUSION: Conservative management seems a safe and justified approach for women younger than 25 years with CIN2.

Regression and Progression Predictors of CIN2 in Women Younger Than 25 Years.

OBJECTIVE: The purpose of this study was to review the management and outcome of cervical intraepithelial neoplasia 2 (CIN2) in women younger than 25 years. METHODS: A retrospective review was performed, investigating women younger than 25 years at the time of diagnosis with biopsy-proven CIN2 between January 1, 2010, and December 31, 2014, who were seen in the colposcopy clinic at the Queen Elizabeth II Hospital in Halifax, Nova Scotia, Canada. The regression, persistence, and progression rate of CIN2 in conservative managed women were evaluated, and potential risk factors were examined. Colposcopy, cytologic, and histopathologic findings were compared with women with immediate treatment (<6 months). RESULTS: Of the 319 women included in the study, 108 women received immediate treatment, and 211 women were managed conservatively; of these, 144 women remained untreated, and 67 women received treatment 6 months or greater. From the women managed conservatively, 150 women (71.1%) showed regression, 26 women (12.3%) had persistent disease, and 35 women (16.6%) progressed, with a median follow-up of 15.1 months. None of the women included in the study progressed to invasive cancer. The hazard ratio for time to progression was 2.40 for women who smoked (p = 0.006). CONCLUSIONS: A conservative approach of CIN2 is the preferred management option for women younger than 25 years. Smoking was identified as a risk factor for progression.