Immediate referral to colposcopy versus cytological surveillance for low-grade cervical cytological abnormalities in the absence of HPV test: A systematic review and a meta-analysis of the literature

Comparative study of treatment efficacy in severe intraepithelial squamous cell lesions and preinvasive cervical cancer by conization and chlorin e6-mediated fluorescence-assisted systemic photodynamic therapy

BACKGROUND

Cervical cancer (CC) occupies a leading position in incidence among young women of reproductive age. In this connection, it is urgent to search for the most effective approaches to the diagnosis and treatment of this pathology. The purpose of the study was to evaluate the effectiveness of the PDT method using Cе6 with the control of the photobleaching using video and spectral fluorescence diagnostic methods, to develop the method of fluorescence-assisted systemic photodynamic therapy mediated with chlorin e6 for treatment CIN 3 and CIS.

MATERIALS AND METHODS

A randomized comparative clinical study was conducted involving 94 women aged 18 to 49 years with histologically verified severe intraepithelial squamous cell lesions of the cervix or preinvasive cervical cancer. The patients were included in 2 groups: in the first group conization of the cervix was performed with curettage of the remaining part of the cervical canal; patients in the second group underwent the chlorin e6-mediated fluorescence-assisted systemic photodynamic therapy.

RESULTS

The absolute majority of patients in the main group after the first course of chlorin e6-mediated fluorescence-assisted systemic photodynamic therapy showed normalization of cytological parameters and colposcopic picture, while women from the comparison group showed signs of cervical lesions statistically significantly more often. These changes corresponded to the dynamics of the proliferation markers expression in the cells of intraepithelial squamous cell lesions. Also, patients of the second group who were planning a pregnancy had better reproductive outcomes after treatment compared to those of the first group.

CONCLUSION

In general, higher clinical efficacy and safety of the use of the chlorin e6-mediated fluorescence-assisted systemic photodynamic therapy in the treatment of intraepithelial squamous cell lesions and preinvasive cervical cancer have been established compared to the use of standard treatment methods.

Colposcopy referral rates post-introduction of primary screening with human papillomavirus testing: evidence from a large British Columbia cohort study

Background

Shifting from cytology to human papillomavirus (HPV)-based cervical cancer screening will initially increase colposcopy referrals. The anticipated impact on health systems has been raised as a concern for implementation. It is unclear if the higher rate of colposcopy referrals is sustained after initial HPV-based screens or reverts to new lower baselines due to earlier detection and treatment of precancer. This study aimed to investigate long-term rates of colposcopy referrals after participation in HPV-based screening.

Methods

Participants of HPV for Cervical Cancer Screening trial (HPV FOCAL) received one (HPV1, N = 6204) or two (HPV2, N = 9540) HPV-based screens. After exit, they returned to British Columbia's (BC) cytology screening program. A comparison cohort from the BC screening population (BCS, N = 1,140,745) was identified, mirroring trial inclusion criteria. All participants were followed for 10-14 years through the provincial screening registry. Colposcopy referral rates per 1000 screens were calculated for each group. Trial colposcopy referrals for HPV1 and HPV2 were calculated under two referral scenarios: (1) all HPV positive referred to colposcopy; (2) cytology triage with ASCUS or greater referred to colposcopy. Colposcopy referrals from post-trial screens in HPV1 an HPV2 and all screens in BCS were based on actual recommendations from the screening program. A multivariable flexible survival regression model compared hazard ratios (HR) throughout follow-up.

Findings

Scenario 2 referral rates were higher during initial HPV screen(s) vs cytology screen (HPV1: 28 per 1000 screens (95% CI: 24, 33), HPV2: 32 per 1000 screens (95% CI: 29, 36), BCS: 8 per 1000 screens (95% CI: 8.9)). However, post-trial rates in HPV1 and HPV2 were significantly lower than in BCS. Cumulative rates in HPV1 and HPV2 approached the cumulative rate in BCS 11-12 years after HPV-based screening (HPV1: 11 per 1000 screens (95% CI: 10, 12), HPV2: 16 per 1000 screens (95% CI: 15-17), BCS: 11 per 1000 screens (95% CI: 10, 11)). Adjusted models demonstrated reductions in referral rates in HPV1 (HR = 0.6, 95% CI: 0.5, 0.7) and HPV2 (HR = 0.7, 95% CI: 0.6, 0.8) relative to BCS by 54 and 72 months post-final HPV screen respectively.

Interpretation

Reduced colposcopy referral rates were observed after initial rounds of HPV-based screening. After initial HPV screening, referral rates to colposcopy after cytology triage were below the current rates seen in a centralized cytology program after approximately four years. Any expected increase in referrals at initiation of HPV-based screening could be countered by staged program implementation.

Funding

This work was supported by the National Institutes of Health (R01 CA221918), Michael Smith Health Research BC (RT-2021-1595), and the Canadian Institutes of Health Research (MCT82072).

The significance of nonsurgical therapies for cervical infection of high-risk human papilloma virus: A systematic review and meta-analysis

OBJECTIVE

To assess whether nonsurgical therapies were related with clearance of cervical infection of high-risk human papilloma virus (hr-HPV) or regression of mild abnormal cytology related with hr-HPV.

METHODS

Until March 2023, we identified a total of 10 424 women with cervical infection of hr-HPV and 1966 women with mild abnormal cytology related with hr-HPV from 44 studies that met the inclusion criteria.

RESULTS

After systematically retrieving literature, we identified 2317 citations and 44 randomized controlled studies (RCT) were enrolled. Cumulative results suggested women with cervical infection of hr-HPV might benefit from nonsurgical therapies. Both the clearance of hr-HPV (OR: 3.83, I2  = 99%, p < 0.00001) and regression of mild abnormal cytology related with hr-HPV (OR: 3.12, I2  = 63%, p < 0.00001) were significantly higher than control group. Subgroup analysis stratified by systematic therapy, topical therapy, traditional Chinese medicines (TCMs), and presistent hr-HPV got consistent results. There was substantial heterogeneity between trials (I2  = 87% for clearance of hr-HPV and 63% for regression of cytology), sensitivity analysis was performed by excluding single study one by one, and found the cumulative results were stable and dependable. Both the funnel plots for clearance of hr-HPV and regression of abnormal cytology were asymmetrical, significant publication bias might exist.

CONCLUSION

Nonsurgical therapies might benefit women who had a cervical infection of hr-HPV with/without mild abnormal cytology related with hr-HPV. Both the clearance of hr-HPV and regression of abnormal cytology were significantly higher than control group. More studies with less heterogeneity were needed urgently to draw concrete conclusion.

Role of colposcopy in the management of women with abnormal cytology

Cytology identifies the women who are at higher risk of harboring high-grade cervical premalignant lesions or invasive cancer. However, a diagnostic test such as colposcopy is crucial for women with abnormal cytology for localization of the abnormality, confirmation of diagnosis, and appropriate management. To standardize this subjective technique and to minimize the interobserver variations, Swede scoring system was introduced. The revised colposcopic nomenclature of the International Federation of Cervical Pathology and Colposcopy in 2011 included various normal and abnormal colposcopic findings and gives a description of colposcopic features which improves its accuracy over the colposcopic indices. There is consensus agreement that cytology indicative of high-grade lesions (ASC-H and HSIL in the Bethesda system) should engender immediate referral for colposcopy and biopsy. The management of women who have equivocal or borderline cytology of low-grade abnormalities (ASCUS/LSIL) is still under deliberation. It is generally agreed to have an HPV triage for women with equivocal cytology. Based on the latest recommendations, the current chapter provides an extensive overview of the role of colposcopy in the management of women with various abnormalities reported on Pap smear.

Comparative performance of the human papillomavirus test and cytology for primary screening for high-grade cervical intraepithelial neoplasia at the population level

The World Health Organization recommends high-risk human papillomavirus (hrHPV)-based screening for women 39 to 49 years, based on the greater accuracy of hrHPV-based screening for cervical cancer detection. Many cervical cancer screening programs have incorporated hrHPV testing and multiple early cervical cancer detection strategies have been evaluated, mostly under controlled conditions. However, there are few evaluations of combined hrHPV and cytology strategies post-implementation at the population level. Our study sought to estimate the relative yield of hrHPV testing compared to cervical cytology, as a primary screening test for cervical intraepithelial neoplasia grade 2+ (CIN2+), used at the population level. We analyzed screening data from Mexico's public cervical cancer prevention program from 2010 to 2015 in women 35 to 64 years. The study population consisted of two cohorts: one from a total of 2 881 962 cytology-based screening tests and another from a total of 2 004 497 hrHPV-based screening tests, which are concurrent in time. We performed a relative yield analysis using Poisson regression models to compare the effectiveness of hrHPV testing for CIN2+ with cervical cytology. A total of 4 886 459 records were analyzed, including 23 999 biopsies; 0.12% (n = 6166) had a CIN2+ histologic diagnosis. hrHPV testing with cytological triage detects twice as many CIN2+ cases as screening using cytology alone.

Comparison between Urine and Cervical High-Risk HPV Tests for Japanese Women with ASC-US

Most uterine cervical cancers are caused by the persistent infection of the high-risk human papillomavirus (hrHPV). Thus, the hrHPV-DNA test, which examines specimens from the cervix, is the standard screening method as well as cytology in western countries. Urine sampling for the hrHPV-DNA test would be easier and help improving screening rates. This study prospectively investigated the concordance between urine and cervical hrHPV tests for patients with atypical squamous cells of undetermined significance (ASC-US) in cervical cytology. We recruited 338 women with the cytologic diagnosis of ASC-US and performed hrHPV-DNA tests to both samples from the uterine cervix and first void urine, using the Cobas 4800 system. In all hrHPV genotypes, the simple concordance rate was 90.8% (307/338) and the Kappa statistic value was 0.765, which shows substantial concordance. The positive concordance rate was 70.5% (74/105), which was the rate excluding women who had negative results in both tests. When limited to types 16 and 18, the simple concordance rate was 98.8% (334/338), and the Kappa statistical value was calculated to be 0.840, which showed almost perfect concordance. The positive concordance rate resulted in 81.8% (18/22). We conclude that the urine hrHPV-DNA test could substitute the cervical test in women with ASC-US.

Reliability and diagnostic performance of smartphone colposcopy

OBJECTIVE

To evaluate the interobserver and intraobserver reliability of smartphone colposcopy (SPC) versus conventional colposcopy and to determine diagnostic performance.

METHODS

A smartphone back camera was used to capture cervical images before and after application of acetic acid, and after application of lugol solution. Captured images were reviewed independently by two experienced colposcopists and findings were noted as per colposcopy. Smartphone-based diagnostic performance was calculated, and kappa statistics were used for measurement of agreement between SPC and conventional colposcopy findings.

RESULTS

A total of 114 women were included in the study. The kappa statistic for intraobserver reliability was 0.77 for both normal colposcopic findings and the transformation zone, indicating substantial agreement. Kappa values were 0.54 for acetowhite epithelium, 0.51 for lugol staining, and 0.51-0.60 for atypical vascularization. Kappa values for interobserver reliability were 0.76 for normal colposcopic findings, 0.56 for acetowhite epithelium, and 0.60 for lugol staining. The sensitivity, specificity, PPV, and NPV of SPC for CIN2+ were 88.2 (95% CI, 72.5-96.7), 48.7 (95% CI, 37.4-60.2), 0.42 (95% CI, 0.36-0.48), and 0.91 (95% CI, 0.79-0.96), respectively.

CONCLUSION

SPC showed substantial agreement between the histologic diagnoses based on the captured images and conventional colposcopic findings.

The early detection of cervical cancer. The current and changing landscape of cervical disease detection

Cervical cancer prevention has undergone dramatic changes over the past decade. With the introduction of human papillomavirus (HPV) vaccination, some countries have seen a dramatic decline in HPV-mediated cervical disease. However, widespread implementation has been limited by economic considerations and the varying healthcare priorities of different countries, as well as by vaccine availability and, in some instances, vaccine hesitancy amongst the population/government. In this environment, it is clear that cervical screening will retain a critical role in the prevention of cervical cancer and will in due course need to adapt to the changing incidence of HPV-associated neoplasia. Cervical screening has, for many years, been performed using Papanicolaou staining of cytology samples. As our understanding of the role of HPV in cervical cancer progression has advanced, and with the availability of sensitive detection systems, cervical screening now incorporates HPV testing. Although such tests improve disease detection, they are not specific, and cannot discriminate high-grade from low-grade disease. This has necessitated the development of effective triage approaches to stratify HPV-positive women according to their risk of cancer progression. Although cytology triage remains the mainstay of screening, novel strategies under evaluation include DNA methylation, biomarker detection and the incorporation of artificial intelligence systems to detect cervical abnormalities. These tests, which can be partially anchored in a molecular understanding of HPV pathogenesis, will enhance the sensitivity of disease detection and improve patient outcomes. This review will provide insight on these innovative methodologies while explaining their scientific basis drawing from our understanding of HPV tumour biology.

High-risk Human Papillomavirus Testing for Triage of Women with Previous Cytological Abnormalities from the Vale do Ribeira Region

OBJECTIVE

 To evaluate the performance of the hybrid capture 2 (HC2) high-risk papillomavirus (hrHPV) assay and cytological test in women with previous abnormalities, to detect cervical intraepithelial neoplasia grade 2 or worse (≥ CIN 2).

METHODS

 A cytological test and HC2 (Qiagen, Gaithersburg, Maryland, EUA) for hrHPV were conducted in 359 liquid-based (Sure Path, Becton Dickinson, TriPath Imaging, Burlington, NC, USA) samples collected from women from the Vale do Ribeira Region, during July 2013 and September 2015 with previous cytology classified as atypical squamous cells of undetermined significance (ASC-US), low-grade squamous intraepithelial lesion (LSIL), atypical squamous cells, cannot exclude high-grade squamous intraepithelial lesions (ASC-H), and atypical glandular cells (AGC). The histopathological examination was conducted in 179 women. The performance evaluations were calculated using the "exact" Clopper-Pearson 95% confidence interval (CI) test by MEDCALC (Medcalc Software Ltd, Ostend, Belgium).

RESULTS

 The ≥ CIN 2 frequency was 11.7% (21/179). The HC2 for hrHPV and repeat cytology to detect ≥ CIN 2 obtained, respectively, a sensitivity of 90.5% (95%CI = 69.6-98.8) and 90.5%, (95%CI = 69.6-98.8), a specificity of 65.8% (95% CI = 57.9-73.2) and 43.7% (95%CI = 35.8-51.8), a positive predictive value of 26.0% (95% CI = 21.4-31.3) and 17.6%, (95%CI = 14.9-20.6), and a negative predictive value of 98.1% (95%CI = 93.3-99.5) and 97.2% (95% CI = 90.1-99.2).

CONCLUSION

 Hybrid capture 2 for hrHPV improves the performance of the detection of ≥ CIN 2, without compromising sensitivity, and provides a greater safety margin to return to the triennial screening of women undergoing follow-up due to previous abnormalities, without underlying ≥ CIN 2.

Real-Time Targeted Genome Profile Analysis of Pancreatic Ductal Adenocarcinomas Identifies Genetic Alterations That Might Be Targeted With Existing Drugs or Used as Biomarkers

BACKGROUND & AIMS

It has been a challenge to select treatment for patients with pancreatic ductal adenocarcinomas (PDACs) based on genome alterations. We performed targeted genomic profile analyses of a large number of PDACs to assess the full spectrum of actionable genomic alterations.

METHODS

We performed targeted genomic profile analyses of 3594 PDAC samples from an international cohort, including capture-based targeted genomic profiling of as many as 315 cancer-associated genes and intron regions of 28 genes that are rearranged in cancer cells. Tumor mutation burden (TMB) and microsatellite instability (MSI) status were also assessed. TMB was calculated across a 1.14-megabase region; TMB-high was defined as ≥20 mutations/megabase. MSI-high status was assigned based on analysis of 114 intron homopolymer loci.

RESULTS

KRAS, TP53, CDKN2A, and SMAD4 were the most frequently altered genes in PDAC. We found KRAS mutations in 88% of samples. Among PDACs without mutations in KRAS, we found alterations in genes whose products are in the mitogen-activated protein kinase signaling pathway and are candidate drug targets (actionable targets, n = 132; 4%), as well as gene fusions (n = 51), gene amplifications (n = 35), genes with missense mutations (n = 30), and genes that contain deletions (n = 16). Many of these encode proteins in receptor tyrosine kinase, RAS, or mitogen-activated protein kinase signaling pathways. Aside from TP53, alterations in genes encoding DNA damage repair proteins (BRCA and FANC) were detected in 14% of PDACs. Among PDACs evaluated for MSI (n = 2563) and TMB (n = 1021), MSI-high and/or TMB-high phenotypes were detected in 0.5% of samples. Alterations in FGF23, CCND2, PIK3CA, and FGF6 were more commonly detected in intraductal papillary mucinous neoplasm-associated PDACs.

CONCLUSIONS

In targeted genomic profile analyses of 3594 PDACs, we found 17% to contain genomic alterations that might make the tumor cells susceptible to currently used anticancer agents. We identified mutations in genes that could contribute to progression of intraductal papillary mucinous neoplasms into malignancies. These alterations might be used as biomarkers for early detection.

Over Expressed TKTL1, CIP-2A, and B-MYB Proteins in Uterine Cervix Epithelium Scrapings as Potential Risk Predictive Biomarkers in HR-HPV-Infected LSIL/ASCUS Patients

High oncogenic risk human papillomaviruses (HR-HPVs) promote cervical carcinoma development, the fourth most common feminine cancer. A slow oncodevelopmental phase—defined histopathologically as Cervical Intraepithelial Neoplasia (CIN) grades 1–3, or cytologically as Low- or High-grade Squamous Intraepithelial Lesions (LSIL or HSIL)—precedes the malignancy. Cervical carcinoma screenings through HR-HPV genotyping and Pap smears are regularly performed in Western countries. Faulty cytology screening or genotyping or patients' non-compliance with follow-ups can let slip an oncoprogression diagnosis. Novel biomarker tests flanking HR-HPV genotyping and cytology could objectively predict the risk of disease progression thus helping triage LSIL/ASCUS patients. Here, anonymized leftovers of fresh cervical epithelium scrapings from twice (LSIL/ASCUS and HR-HPV DNA)-positive and twice (Pap smear- and HR-HPV DNA)-negative (control) patients in a proteome-preserving solution served to assess the biomarker worth of three cervical carcinoma-related proteins, i.e., B-MYB (or MYBL2), Cancerous Inhibitor of PP2A (CIP-2a), and transketolase-like1 (TKTL1). Leftovers anonymity was strictly kept and storage at −80°C, protein extraction, immunoblotting, and band densitometry were blindly performed. Only after tests completion, the anonymous yet code-corresponding HR-HPV-genotyping and cytology data allowed to assign each sample to the twice-positive or twice-negative group. Descriptive statistics showed that the three proteins levels significantly increased in the twice-positive vs. twice-negative scrapings. Diagnostic ROC curve analysis identified each protein's Optimal Decision Threshold (OTD) showing that TKTL1 and CIP-2a are stronger risk predictive biomarkers (Sensitivity, 0.91–0.93; Specificity, 0.77–0.83) than B-MYB. Logistic Regression coupled with Likelihood-Ratio Tests confirmed that a highly significant relation links increasing TKTL1/CIP-2a/B-MYB protein levels in twice-positive cervical scrapings to the risk of HR-HPV-driven oncoprogression. Finally, a 3 year clinical follow-up showed that 13 patients (50% of total) of the twice-positive group with biomarker values over OTDs compliantly underwent scheduled colposcopy and biopsy. Of these, 11 (i.e., 84.7%) received a positive histological diagnosis, i.e., CIN1 (n = 5; 38.5%) or CIN2/CIN2+ (n = 6; 46,2%). Therefore, TKTL1/CIP-2a/B-MYB protein levels could objectively predict oncoprogression risk in twice (HR-HPV- and Pap smear)-positive women. Further studies will assess the translatability of these findings into clinical settings.

Atypical squamous cells of undetermined significance and low-grade squamous intraepithelial lesion triage in Korean women: Revisiting the 2012 American Society of Colposcopy and Cervical Pathology screening guidelines

Objective

To determine whether triage for atypical squamous cells of undetermined significance (ASC-US) and low-grade squamous intraepithelial lesion (LSIL) from the updated American Society for Colposcopy and Cervical Pathology cervical cancer screening guidelines is applicable in Korean women.

Methods

We investigated women with ASC-US or LSIL including referred from local hospitals visited for cervical cancer screening at Korea University Guro Hospital from February 2004 to December 2014. Detailed information on the results of Papanicolaou (Pap) smears, human papillomavirus (HPV) DNA tests, and cervical biopsies were collected through chart review. Cervical biopsy results were compared in eligible women according to individual Pap smear findings and HPV DNA status.

Results

Of 216,723 possible cases, 3,196 were included. There were 212 (6.6%) women with ASC-US and 500 (15.6%) with LSIL. The risk of ≥cervical intraepithelial neoplasia (CIN) 2 was significantly higher in women who were ASC-US/HPV+ than ASC-US/HPV- and LSIL/HPV+ than LSIL/HPV- (93.3% vs. 6.7% and 96.7% vs. 3.3%, P<0.001 and P<0.001, respectively). The risk of ≥CIN 3 was also significantly higher in women who were ASC-US/HPV+ than ASC-US/HPV- and LSIL/HPV+ than LSIL/HPV- (97.0% vs. 3.0% and 93.0% vs. 7.0%, P<0.001 and P<0.001, respectively). Age-stratified analysis revealed that more CIN 2 or CIN 3 was diagnosed in women aged 30 to 70 with ASC-US or LSIL when HPV DNA was present.

Conclusion

Observation with Pap and HPV DNA tests rather than immediate colposcopy is a reasonable strategy for ASC-US or LSIL when the HPV DNA test is negative, especially in women aged 30 to 70. Reflection of these results should be considered in future Korean screening guidelines.

Immediate referral to colposcopy versus cytological surveillance for minor cervical cytological abnormalities in the absence of HPV test

BACKGROUND

A significant number of women are diagnosed with minor cytological abnormalities on cervical screening. Many authorities recommend surveillance as spontaneous regression might occur. However, attendance for cytological follow-up decreases with time and might put some women at risk of developing invasive disease.

OBJECTIVES

To assess the optimum management strategy for women with minor cervical cytological abnormalities (atypical squamous cells of undetermined significance - ASCUS or low-grade squamous intra-epithelial lesions - LSIL) at primary screening in the absence of HPV (human papillomavirus) DNA test.

SEARCH METHODS

We searched the following electronic databases: Cochrane Central Register of Controlled Trials (CENTRAL Issue 4, 2016), MEDLINE (1946 to April week 2 2016) and Embase (1980 to 2016 week 16).

SELECTION CRITERIA

We included randomised controlled trials (RCTs) comparing immediate colposcopy to cytological surveillance in women with atypical squamous cells of undetermined significance (ASCUS/borderline) or low-grade squamous intra-epithelial lesions (LSIL/mild dyskaryosis).

DATA COLLECTION AND ANALYSIS

The primary outcome measure studied was the occurrence of cervical intra-epithelial neoplasia (CIN). The secondary outcome measures studied included default rate, clinically significant anxiety and depression, and other self-reported adverse effects.We classified studies according to period of surveillance, at 6, 12, 24 or 36 months, as well as at 18 months, excluding a possible exit-examination. We calculated pooled risk ratios (RR) and 95% confidence intervals (CI) using a random-effects model with inverse variance weighting. Inter-study heterogeneity was assessed with I² statistics.

MAIN RESULTS

We identified five RCTs with 11,466 participants that fulfilled the inclusion criteria. There were 18 cases of invasive cervical cancer, seven in the immediate colposcopy and 11 in the cytological surveillance groups, respectively. Although immediate colposcopy detects CIN2+ and CIN3+ earlier than cytology, the differences were no longer observed at 24 months (CIN2+: 3 studies, 4331 women; 17.9% versus 18.3%, RR 1.14, CI 0.66 to 1.97; CIN3+: 3 studies, 4331 women; 10.3% versus 11.9%, RR 1.02, CI 0.53 to 1.97). The inter-study heterogeneity was considerable (I² greater than 90%). Furthermore, the inclusion of the results of the exit examinations at 24 months, which could inflate the CIN detection rate of cytological surveillance, may have led to study design-derived bias; we therefore considered the evidence to be of low quality.When we excluded the exit examination, the detection rate of high-grade lesions at the 18-month follow-up was higher after immediate colposcopy (CIN2+: 2 studies, 4028 women; 14.3% versus 10.1%, RR 1.50, CI 1.12 to 2.01; CIN3+: 2 studies, 4028 women, 7.8% versus 6.9%, RR 1.24, CI 0.77 to 1.98) both had substantial inter-study heterogeneity (I² greater than 60%) and we considered the evidence to be of moderate quality).The meta-analysis revealed that immediate referral to colposcopy significantly increased the detection of clinically insignificant cervical abnormalities, as opposed to repeat cytology after 24 months of surveillance (occurrence of koilocytosis: 2 studies, 656 women; 32% versus 21%, RR 1.49, 95% CI 1.17 to 1.90; moderate-quality evidence) incidence of any CIN: 2 studies, 656 women; 64% versus 32%, RR 2.02, 95% CI 1.33 to 3.08, low-quality evidence; incidence of CIN1: 2 studies, 656 women; 21% versus 8%, RR 2.58, 95% CI 1.69 to 3.94, moderate-quality evidence).Due to differences in trial designs and settings, there was large variation in default rates between the included studies. The risk for default was higher for the repeat cytology group, with a four-fold increase at 6 months, a six-fold at 12 and a 19-fold at 24 months (6 months: 3 studies, 5117 women; 6.3% versus 13.3%, RR 3.85, 95% CI 1.27 to 11.63, moderate-quality evidence; 12 months: 3 studies, 5115 women; 6.3% versus 14.8%, RR 6.39, 95% CI 1.49 to 29.29, moderate-quality evidence; 24 months: 3 studies, 4331 women; 0.9% versus 16.1%, RR 19.1, 95% CI 9.02 to 40.43, moderate-quality evidence).

AUTHORS' CONCLUSIONS

Based on low- or moderate-quality evidence using the GRADE approach and generally low risk of bias, the detection rate of CIN2+ or CIN3+ after two years does not appear to differ between immediate colposcopy and cytological surveillance in the absence of HPV testing, although women may default from follow-up. Immediate colposcopy probably leads to earlier detection of high-grade lesions, but also detects more clinically insignificant low-grade lesions. Colposcopy may therefore be the first choice when good compliance is not assured. These results emphasize the need for an accurate reflex HPV triage test to distinguish women who need diagnostic follow-up from those who can return safely to routine recall.