Competing-risks regression models in analysis of biomarkers as predictors of high-risk human papillomavirus (HPV) infection outcomes and incident CIN in the LAMS cohort.

To assess the prediction potential of a 5-biomarker panel for detecting high-risk human papillomavirus (HR-HPV) infections and/or cervical intraepithelial neoplasia (CIN) progression. Five biomarkers, lipocalin, plasminogen activator inhibitor-2, p300, interleukin-10, and stratifin, were assessed in cervical biopsies from 225 women of the Latin American Screening Study. Competing-risks regression models were constructed to assess their predictive power for (i) HR-HPV outcomes (negative, transient, or persistent infection) and (ii) CIN outcomes (no progression, incident CIN1, CIN2, or CIN3). p300, LCN2, stratifin were significantly associated with prevalent HR-HPV but lost their significance in multivariate analysis. In the multivariate model, only p300 was an independent predictor of CIN3 (odds ratio=2.63; 95% confidence interval, 1.05-6.61; P=0.039). In univariate competing-risks regression, lipocalin predicted permanent HR-HPV-negative status, but in the multivariate model, IL-10 emerged as a independent predictor of HPV-negative status (subhazard ratio=4.04; 95% confidence interval, 1.81-9.01; P=0.001). The clinical value of the panel in predicting longitudinal outcomes of HR-HPV infection and/or incident CIN is limited.

Performance characteristics of Pap test, VIA, VILI, HR-HPV testing, cervicography, and colposcopy in diagnosis of significant cervical pathology.

We sought to evaluate the performance of diagnostic tools to establish an affordable setting for early detection of cervical cancer in developing countries. We compared the performance of different screening tests and their feasibility in a cohort of over 12,000 women: conventional Pap smear, liquid-based cytology, visual inspection with acetic acid (VIA), visual inspection with Iodine solution (VILI), cervicography, screening colposcopy, and high-risk human papillomavirus (HPV) testing (HR-HPV) collected by physician and by self-sampling. HR-HPV assay collected by the physician has the highest sensitivity (80 %), but high unnecessary referrals to colposcopy (15.1 %). HR-HPV test in self-sampling had a markedly lower (57.1 %) sensitivity. VIA, VILI, and cervicography had a poor sensitivity (47.4, 55, and 28.6 %, respectively). Colposcopy presented with sensitivity of 100 % in detecting CIN2+, but the lowest specificity (66.9 %). Co-testing with VIA and VILI Pap test increased the sensitivity of stand-alone Pap test from 71.6 to 87.1 % and 71.6 to 95 %, respectively, but with high number of unnecessary colposcopies. Co-testing with HR-HPV importantly increased the sensitivity of Pap test (to 86 %), but with high number of unnecessary colposcopies (17.5 %). Molecular tests adjunct to Pap test seems a realistic option to improve the detection of high-grade lesions in population-based screening programs.

Hormonal contraceptives and the length of their use are not independent risk factors for high-risk HPV infections or high-grade CIN.

AIMS: To evaluate the role of hormonal contraceptives as a risk factor of high-risk human papillomavirus (HR-HPV), cervical intraepithelial lesions (CIN) and cervical cancer in our multi-center population-based LAMS (Latin American Screening) study. METHODS: A cohort study with >12,000 women from Brazil and Argentina using logistic regression to analyze the covariates of hormonal contraception (HOC - oral, injections, patches, implants, vaginal ring and progesterone intrauterine system) use followed by multivariate modeling for predictors of HR-HPV and CIN2+. RESULTS: HR-HPV infection was a consistent risk factor of high-grade CIN in all three groups of women. The length of HOC use was not significantly related to high-grade squamous intraepithelial lesions (HSIL)+ Pap (p = 0.069), LSIL+ Pap (p = 0.781) or ASCUS+ (p = 0.231). The same was true with the length of HOC use and histology CIN3+ (p = 0.115) and CIN2+ (p = 0.515). Frequently, HOC users have previously shown more HPV-related lesions, as well as lower HPV prevalence if they were current smokers. But HOC use and time of usage were not independent risk factors of either HR-HPV infection or high-grade CIN using multiple logistic regressions. CONCLUSIONS: No evidence was found for an association between the use of HOC with an increased risk for HR-HPV infection or high-grade CIN in this cohort.

Up-regulation of lipocalin 2 is associated with high-risk human papillomavirus and grade of cervical lesion at baseline but does not predict outcomes of infections or incident cervical intraepithelial neoplasia.

Our objective was to assess whether neutrophil gelatinase-associated lipocalin (NGAL)/lipocalin 2 (LCN2) expression in cervical human papillomavirus (HPV) lesions has implications on the outcome of HPV infections or disease progression. Cervical biopsy specimens from 225 women in the Latin American Screening study were analyzed for NGAL/LCN2 expression using immunohistochemical analysis, to assess associations with cervical intraepithelial neoplasia (CIN) grade, high-risk HPV, and in predicting outcomes of high-risk (HR)-HPV infections. Expression of NGAL/LCN2 increased with lesion grade (odds ratio [OR], 3.86; 95% confidence interval [CI], 1.53-9.71; P = .001). Up-regulation was also related to HR-HPV detection (OR, 2.21; 95% CI, 1.15-4.24; P = .016) and showed a linear relationship to HR-HPV load (P = .002). NGAL/LCN2 expression was of no value in predicting the outcomes of HR-HPV infections or the surrogate end points (incident CIN 1+ and CIN 2+) of progressive disease. Because the SV40 large T antigen is a powerful up-regulator of this lipocalin, up-regulation of NGAL/LCN2 in CIN is probably induced by HR-HPV E6 oncoprotein, most likely by eliminating its normal transcription repression exerted by wild-type p53.

p300 expression is related to high-risk human papillomavirus infections and severity of cervical intraepithelial neoplasia but not to viral or disease outcomes in a longitudinal setting.

To evaluate the role of the expression of the transcription factor p300 as an independent predictor of high-risk human papillomavirus (HR-HPV) infections and outcome of the cervical disease.Cervical biopsy samples taken at enrolment from 225 women of the Latin American Screening study cohort were analyzed for p300 using immunohistochemistry to assess its value as predictor of (a) cervical intraepithelial neoplasia (CIN) grade, and (b) HR-HPV at baseline, as well as (c) outcomes of HR-HPV infections, and (d) development of incident CIN as surrogate endpoints of progressive disease.There was a significant linear trend in increasing upregulation (=pattern shift) of p300 (P=0.0001) in parallel with increasing grade of CIN. When dichotomized (normal/moderately increase vs. strong-intense), upregulated p300 expression predicted CIN3+ with odds ratio=4.16 (95% confidence interval: 1.95-8.86) (P=0.0001) and CIN2+ with odds ratio=3.48 (95% confidence interval: 1.86-6.48) (P=0.0001). p300 was upregulated more often in HR-HPV+ lesions than in those remaining negative. Semiquantitative viral loads were also directly related to upregulation of p300 (P=0.036), but p300 was not a significant predictor of disease progression to either CIN1+ or CIN2+.p300 expression was upregulated in CIN lesions and related to detection and viral load of HR-HPV but not to their outcome or to incident CIN.

Up-regulation of 14-3-3sigma (Stratifin) is associated with high-grade CIN and high-risk human papillomavirus (HPV) at baseline but does not predict outcomes of HR-HPV infections or incident CIN in the LAMS study.

To assess whether the potentially high-risk (HR) human papillomavirus (HPV)-related up-regulation of 14-3-3sigma (stratifin) has implications in the outcome of HPV infections or cervical intraepithelial neoplasia (CIN) lesions, cervical biopsy specimens from 225 women in the Latin American Screening Study were analyzed for 14-3-3sigma expression using immunohistochemical analysis. We assessed its associations with CIN grade and HR HPV at baseline and value in predicting outcomes of HR-HPV infections and the development of incident CIN 1+ and CIN 2+. Expression of 14-3-3sigma increased in parallel with the lesion grade. Up-regulation was also significantly related to HR-HPV detection (P = .004; odds ratio, 2.71; 95% confidence interval, 1.37-5.35) and showed a linear relationship to HR-HPV loads (P = .003). 14-3-3sigma expression was of no value in predicting the outcomes (incident, persistent, clearance) of HR-HPV infections or incident CIN 1+ and CIN 2+. 14-3-3sigma is not inactivated in cervical carcinoma and CIN but is up-regulated on transition from CIN 2 to CIN 3. Its normal functions in controlling G(1)/S and G(2)/M checkpoints are being bypassed by HR HPV.

Up-regulation of plasminogen activator inhibitor-2 is associated with high-risk HPV and grade of cervical lesion at baseline but does not predict outcomes of high-risk HPV infections or incident CIN.

Protease inhibitor serpin-B2 (plasminogen activator inhibitor-2 [PAI-2]) protects pRb from degradation in human papillomavirus (HPV)-18+ HeLa cells. Our objective was to assess whether the pRb-mediated HPV-suppressive effect of PAI-2 in cancer cell lines has implications in the outcome of HPV infections. Cervical biopsy specimens from 225 women were analyzed for PAI-2 expression to assess its value as a predictor of cervical intraepithelial neoplasia (CIN) grade, high-risk (HR) HPV at baseline, outcomes of HR-HPV infections, and the development of incident CIN. PAI-2 expression increased in parallel with lesion grade. Nuclear PAI-2 expression was significantly related to HR-HPV detection and had a linear relationship with HR-HPV load. PAI-2 expression was of no value in predicting the outcomes of HR-HPV infections. The same was true for PAI-2 as a predictor of surrogate end points (incident CIN 1+, CIN 2+) of progressive disease. PAI-2 expression is up-regulated on transition from CIN 2 to CIN 3. The HR-HPV suppressive effects of PAI-2 were not related to more favorable outcomes of HR-HPV infections or lower risk of disease progression to CIN.

Immunosuppressive cytokine Interleukin-10 (IL-10) is up-regulated in high-grade CIN but not associated with high-risk human papillomavirus (HPV) at baseline, outcomes of HR-HPV infections or incident CIN in the LAMS cohort.

Bypassing the local immunological defense reactions in the cervix is one of the prerequisites for human papillomaviruses (HPV) infections to progress to intraepithelial neoplasia (CIN). The role of potent immunosuppressive cytokines, e.g., interleukin-10 (IL-10), depressing these local virus-specific immunological responses is incompletely studied. To assess, whether IL-10 expression in cervical HPV lesions has any implications in the outcome of HPV infections or disease progression to CIN. Baseline cervical biopsies from 225 women of the LAMS study sub-cohort were analyzed for IL-10 expression using immunohistochemistry, to assess its associations with CIN grade, and high-risk HPV (HR-HPV) at baseline, as well as in predicting outcomes of HR-HPV infections, and development of incident CIN1+ and CIN2+ in this longitudinal setting. Expression of IL-10 in cervical lesions was up-regulated most often in high-grade CIN, and IL-10 over-expression retained its value as independent predictor of CIN2+ (odds ratio (OR) = 4.92) and CIN3+ (OR = 7.51) also in multivariate model, including HR-HPV and several known covariates of IL-10 expression. Up-regulation was not related to HR-HPV detection, and showed no relationship to HR-HPV viral loads. Using longitudinal predictive indicators (SE, SP, PPV, NPV), IL-10 expression was of no value in predicting (1) the outcomes of HR-HPV infections, or (2) the surrogate endpoints (incident CIN1+, CIN2+) of progressive disease. IL-10 over-expression (along with HR-HPV) was one of the independent covariates of CIN2/3. This immunosuppressive cytokine might play an important role in creating a microenvironment that favors progressive cervical disease and immune evasion by HR-HPV.

Persistent high-risk human papillomavirus infections and other end-point markers of progressive cervical disease among women prospectively followed up in the New Independent States of the Former Soviet Union and the Latin American Screening study cohorts.

BACKGROUND: New end points are needed in future human papillomavirus (HPV) vaccine efficacy studies that accurately predict disease progression. OBJECTIVES: Potential intermediate end points were analyzed in the combined New Independent States of the Former Soviet Union (NIS) and the Latin American Screening (LAMS) study cohorts. STUDY DESIGN AND METHODS: Data files of 2 international screening trials, the NIS (n = 3187) and the LAMS (n = 12,114) study cohorts, were combined, and a subcohort of 1865 (n = 854 and n = 1011 for the NIS and the LAMS, respectively) women prospectively followed up for 19.7 (median, 22.2) months was analyzed for different intermediate end-point markers of disease progression to squamous intraepithelial lesion (SIL), cervical intraepithelial neoplasia grade 1 and higher (CIN1+), and CIN grade 2 and higher (CIN2+) as terminal events. RESULTS: : Altogether, 131 (7.0%), 90 (4.8%), and 39 (2.1%) cases progressed to SIL, CIN1+, and CIN2+, respectively, progression times being equal in the NIS (11.9, 16.8, and 19.6 months) and LAMS (13.6, 14.1, and 15.4 months) cohorts (P = 0.931, P = 0.335, and P = 0.535). The 2 most powerful end-point markers of disease progression to CIN2+ were high-grade squamous intraepithelial lesions based on Papanicolaou test results at 6-month (odds ratio [OR] = 47.1; 95% confidence interval [CI], 17.3-128.7) and 12-month (OR = 21.5; 95% CI, 5.1-90.8) follow-up visits, with longitudinal positive and negative predictive values of 42.1% and 98.0% (6 months) and 33.3% and 97.7% (12 months). Of the virological end points, more than 6 months of persistent high-risk HPV (HR-HPV) was the most powerful predictor of progression to CIN1+ (OR = 18.6; 95% CI, 2.5-136.5), with longitudinal positive and negative predictive values of 10.3% and 99.4%, respectively. No additional benefit was obtained using more than 12 months of persistent HR-HPV end point. CONCLUSIONS: High-grade squamous intraepithelial lesion based on a Papanicolaou test results at 6- or 12-month follow-up visits was the most powerful end point, either considering cytological end points alone or in comparison to any of the virological end points. Of the virological end points, more than 6-month HR-HPV persistence criteria give the most powerful estimate of a progressive disease.

Smoking worsens the prognosis of mild abnormalities in cervical cytology.

OBJECTIVE: To examine the effect of smoking on the incidence of low- and high-grade cervical intraepithelial neoplasia (CIN) in women with a baseline Pap smear of atypical squamous cells (ASC) or a low-grade squamous intraepithelial lesion (LSIL). DESIGN: Prospective study in which a cohort of women with normal colposcopy and ASC/LSIL at baseline were followed at 6-month intervals of up to 36 months. Women were grouped in post-hoc analysis according to their smoking behavior: never (or past) smokers and current smokers. SETTING: This report was based on data from the Latin American Screening Study, conducted in Sao Paulo, Campinas, Porto Alegre (Brazil) and Buenos Aires (Argentina). POPULATION: A subset of 150 women derived from a cohort of 1,011 women. METHODS: Multivariate Cox analysis and Kaplan-Meier curves were used. MAIN OUTCOME MEASURES: Low- and high-grade CIN during follow-up. RESULTS: The only factor related to an increased risk of developing CIN was the positive high-risk (hr) HPV status (hazard ratio (HR) = 3.42; 95% CI: 1.11-9.43). A total of 21 cases of incident CIN were detected during follow-up. Of these, 11 appeared in the group of 67 smokers and 10 among the 83 non-smoker women (log-rank, p=0.33). Smoking status was not associated with the risk of developing CIN (HR = 0.73; 95% CI: 0.40-1.33). However, when restricting the analysis to high-grade CIN only (11 cases), the probability of developing the disease was significantly higher among smokers (p=0.04). CONCLUSIONS: Smoking contributes additional risk for developing high-grade CIN in women with ASC or LSIL cytology but normal colposcopy.

Increased risk of oncogenic human papillomavirus infections and incident high-grade cervical intraepithelial neoplasia among smokers: experience from the Latin American screening study.

BACKGROUND: The purpose of this study was to assess the effect of smoking on the prevalence and incidence of high-risk human papillomavirus (hr-HPV) infection and cervical intraepithelial neoplasia (CIN) in a large sample of Latin American women. METHODS: The study examines baseline data on over 12,000 women included in the Latin American Screening Study (Brazil and Argentina), and over 1000 women followed-up for a period of 36 months. Three groups were formed: never smokers, current, and past smokers. The prevalence of hr-HPV infection and CIN were compared between the study groups. In the prospective analysis, women were controlled at 6-month intervals to assess the cumulative risk of incident hr-HPV infection, smear abnormalities, and CIN. RESULTS: A higher prevalence (21.7%) of hr-HPV infection was found among current smokers as compared to never smokers (16.5%) or past smokers (13.5%). Being current smoker was significantly (P <0.01) associated with hr-HPV detection (OR = 1.6; 95% CI = 1.2-2.1). Being a current smoker was a significant predictor of incident hr-HPV during the follow-up [Hazards ratio (HR) = 1.4; 95% CI 1.0-1.9]. For incident CIN2+, being a past smoker (HR = 3.6; 95% CI 1.6-9.8) or current smoker (HR = 3.6; 95% CI 1.5-8.6) were the significant independent predictors. Current and past smokers had a significantly increased risk of incident CIN2+ (P <0.01). CONCLUSIONS: Smoking increases the risk of contracting hr-HPV infection and modifies the effect of a persistent hr-HPV infection by further increasing the risk of developing CIN2+. It seems that this effect modification persists over several years after smoking cessation.

Interlaboratory quality control in gynecologic cytopathology using the novel CONQUISTADOR software. Interobserver reproducibility in the Latin American screening study.

OBJECTIVE: The recently developed software (CONQUISTADOR), capable of computing all intralaboratory and interlaboratory quality control (QC) indicators, was used to evaluate the diagnostic agreement among 4 cytology laboratories participating in the LAMS Study. STUDY DESIGN: The study was an interlaboratory exchange of specially designed 5 slide sets, each comprising 20 (conventional cytology) slides. At the first step, 80 slides (with "clear-cut" cases) were divided into four sets (A, B, C, D) of 20 specimens, each including inadequate and negative cases as well as in different proportions of all diagnostic TBS 2001 categories. In the second round, a fifth set (E) of 20 slides ("difficult cases") was designed, with all diagnostic categories, ASC and AGC included. Common measures of reproducibility (kappa and weighted kappa), accuracy (SE, SP, PPV, NPV) and 3 indices of diagnostic variability were calculated for sets A-D and set E, separately. RESULTS: For the 5 slide sets together, the weighted kappa was 0.8 (95% CI 0.76-0.85), which is the lower limit of the "almost perfect" ranking of kappa statistics, indicating an excellent interlaboratory agreement. The interlaboratory reproducibility was lower only for the difficult set (E). Similarly, the sensitivity for set E (70.0%) was lower than that (92.1%) for sets A-D. The diagnostic variability indices were not substantially different between the difficult (set E) and clearcut (sets A-D) cases. CONCLUSION: High interlaboratory reproducibility was obtained for sets A-D ("clear-cut" cases), while more interlaboratory variation was evident in the difficult samples. The new CONQUISTADOR software is a valuable tool in calculating the indicators needed in this intralaboratory and interlaboratory.

Conventional Pap smear and liquid-based cytology as screening tools in low-resource settings in Latin America: experience of the Latin American screening study.

OBJECTIVE: To evaluate the performance of the conventional Pap test and liquid-based cytology (LBC) in an ongoing multicenter trial testing optional screening tools (cytology, screening colposcopy, visual inspection with acetic acid, visual inspection with Lugol's Iodine, cervicography and Hybrid Capture II [HCII] (Digene Brazil, São Paulo, Brazil) conventional and self-sampling), for cervical cancer in Brazil and Argentina. STUDY DESIGN: A cohort of 12,107 women attending four clinics (Campinas, São Paulo, Porto Alegre, Buenos Aires) were randomized into the 8 diagnostic arms. Women testing positive with any of the tests were referred for colposcopy, and cervical biopsies were used as the gold standard to assess performance characteristics of the diagnostic tests. Conventional Pap smears were sampled by all clinics (n = 10,240), and LBC (Autocyte PREP, [TriPath Imaging, Burlington, North Carolina, U.S.A.], n=320, and DNA-Citoliq [Digene Brazil], n =1,346) was performed by 1 of the clinics. RESULTS: Conventional Pap smears showed no squamous intraepithelial lesions (normal) in 8,946 (87.4%) and LBC in 1,373 (82.4%). Using high grade squamous intraepithelial lesions (HSIL) as the cutoff, Pap smears predicted high grade (cervical intraepithelial neoplasia [CIN] 3) with OR 63.0 (95% CI, 36.90-107.70), standard error (SE) 59%, SP 97.8%, positive predictive value (PPV) 68.1% and negative predictive value (NPV) 96.7%. The same figures for Autocyte PREP were: OR 9.0 (95% CI, 2.43-33.24), sensitivity (SE) 33.3%, specificity (SP) 100%, PPV 100% and negative PV (NPV) 88.8%. DNA-Citoliq detected CIN 3 as follows: OR 11.8 (95% CI 2.60-53.26), SE 40.0%, SP 94.6%, PPV 40.0% and NPV 94.6%. Lowering the cutoff to low grade squamous intraepithelial lesions increased SE and NPV but compromised SP and PPV. The detection rates for high grade lesions after an atypical squamous cells of undetermined significance diagnosis were similar with the 3 techniques. In our settings, the 3 methods of cervical cytology were slightly different in performance. The conventional Pap smear had the highest SE, while Autocyte PREP had 100% SP and PPV in detecting CIN3 with the HSIL cutoff. All 3 tests had lower SE but higher SP as compared to HCII.

New statistical software for intralaboratory and interlaboratory quality control in clinical cytology. Validation in a simulation study on clinical samples.

OBJECTIVE: To design a statistical software package to provide automated calculations of normal and weighted and 3 indices. STUDY DESIGN: Prompted by the lack of commonly available software to compute weighted kappa and the nonproportionate workload needed to calculate our 3 variability indices manually, the new statistical software package was designed. To demonstrate the performance of the new CONQUISTADOR software, a simulation study (both intralaboratory and interlaboratory) was designed using 5,000 clinical samples randomly selected from a data file of > or = 200,000 conventional Pap smears and programmed to become "analyzed" by 12 cytologists in 5 imaginary laboratories. RESULTS: A representative set of both complete and partial outputs provided by the software, in Excel format (Microsoft, Redmond, Washington, U.S.A.) are shown to illustrate the different functions of the program. In the interlaboratory mode, the software calculates accuracy indicators (sensitivity, specificity, positive and negative predictive value, and their 95% CI), which are not common features of regular statistical packages; kappa and weighted kappa; and their 95% CI (comparison of single laboratories to all laboratories and pairwise comparisons between single laboratories). The 3 diagnostic variability indices can be computed separately for all samples or for only the positive samples. In the intralaboratory mode, the software calculates the same indices for individual cytologists. CONCLUSION: The CONQUISTADOR statistical package has properties that are useful in monitoring cytologic laboratory quality in both intralaboratory and interlaboratory settings. The software will be distributed by the National Institute of Health, Rome, for the delivery costs only.

Evaluation of causes of increased incidence of cervical cancer in Slovenia.

OBJECTIVE: In Slovenia the opportunistic cervical cancer (CC) screening programme has been performed within the regular gynaecological practice since 1960. The incidence rate 28.8/10(5) decreased to 16.1/10(5) in 1982, and increased to 23/10(5) in 1996. To explain the increased CC incidence the patients' screening histories, occurrence of symptoms, and details of preventive measures were studied on the basis of medical records and questionnaire. Errors of cytological screening were analysed by reviewing previous smears. MATERIAL: The answers obtained from 324 women, treated for CC in the period 1995-2000, were analysed in relation to age, stage and histology. The mean women's age was 46.76 +/- 13.07 (S.D.) years (range 23-85 years). After therapy, 271 patients were followed-up by the end of January 2004, (mean follow-up time 80.3 +/- 20 S.D. months, range 29.7-110.3 months). Statistical analysis was performed using Chi-square test. RESULTS: In 208 (80%) cases, CC was detected in stage 1, in 43 (17%) in stages 2A to 3B. Squamous-cell carcinoma (192, 74.1%) was followed by adenocarcinoma (61, 23.5%) and (5, 1.9%) other malignancies. The screening interval ranged from 6 months to 4 years. Statistically significant differences existed between clinical and screening variables. CC was diagnosed in higher stages in women who were ignorant of the Pap test. Re-screened smears (n = 126) showed 27.8% of false negative results. CONCLUSIONS: The reasons for high incidence of CC are poor performance of cytological screening, failures in gynecological examinations and diagnostic procedures, and the patients' negligence of attending regular screening.