Valerija Grunberga

Turku University Hospital, Turku, Province of Western Finland, Finland

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Publications (11)24.85 Total impact

  • Acta Cytologica - ACTA CYTOL. 01/2009; 53:548-557.
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    ABSTRACT: Data are controversial as to the role of menarche age as a risk factor of high-risk human papillomavirus (HR-HPV) infections. The objective of this study was to analyse the risk estimates for age at menarche as determinant of cervical intraepithelial neoplasia (CIN) and HR-HPV infections. A cohort of 3187 women were stratified into three groups according to their age at menarche: (i) women <13 years of age; (ii) those between 13 and 14 years and (iii) women >15 years of age. These groups were analysed for predictors of (a) HR-HPV, (b) high-grade CIN and (c) outcome of HR-HPV and cytological abnormalities during prospective follow-up. All the three groups had identical prevalence of HR-HPV, Papanicolaou smear abnormalities and CIN grades. In contrast to menarche age itself, the time from menarche to the first intercourse (TMI), to the first pregnancy (TMP) and to the first delivery (TMD) were all significant (P = 0.0001) predictors of HR-HPV (but not CIN2) in univariate analysis, but lost their significance in a multivariate model. Outcome of cervical disease and HR-HPV infection was unrelated to menarche age, the latter and the three intervals being not predictors of CIN2 in a multivariate model. In conclusion, age at menarche and the intervals between menarche and (i) onset of sexual activity, (ii) first pregnancy and iii) first delivery, are not independent predictors of HR-HPV infections and CIN2 in multivariate analysis.
    International Journal of STD & AIDS 01/2008; 19(1):16-25. · 1.00 Impact Factor
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    ABSTRACT: Recent evidence implicates smoking as a risk factor for cervical cancer (CC), but the confounding from high-risk human papillomavirus (HPV) infections is not clear. To analyse the role of smoking as an independent predictor of CIN2+ and HR-HPV infections in a population-based prospective (NIS, New Independent States of former Soviet Union) cohort study. A cohort of 3,187 women was stratified into three groups according to their smoking status: (i) women who never smoked; (ii) those smoking in the past; and (iii) women who are current smokers. These groups were analysed for predictors of (a) HR-HPV; (b) high-grade CIN, and (c) outcome of HR-HPV infections and cytological abnormalities during prospective follow-up (n = 854). The three groups were significantly different in all major indicators or risk sexual behaviour (or history) implicating strong confounding. There was no increase in HSIL/LSIL/ASC-US cytology or CIN1+/CIN2+/CIN3+ among current smokers. Only few predictors of HR-HPV and CIN2+ were common to all three groups, indicating strong interference of the smoking status. There was no difference in outcomes of cervical disease or HR-HPV infections between the three groups. In multivariate model, being current smoker was one of the five independent predictors of HR-HPV (P = 0.014), with adjusted OR = 1.52 (95%CI 1.09-2.14). In addition to age, HR-HPV was the only independent predictor of CIN2+ in multivariate model (OR = 14.8; 95%CI 1.72-127.31). These data indicate that cigarette smoking is not an independent risk factor of CIN2+, but the increased risk ascribed to smoking is mediated by acquisition of HR-HPV, of which current smoking was an independent predictor in multivariate model.
    European Journal of Epidemiology 02/2007; 22(10):723-35. · 5.12 Impact Factor
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    ABSTRACT: The growth-controlling functions of the high-risk human papillomaviruses (HPV) depend on their ability to interact with several cellular proteins, including the key regulatory proteins of the cell cycle. We have examined the value of cell cycle regulatory proteins as predictors of the intermediate end point markers in cervical carcinogenesis: (a) grade of cervical intraepithelial neoplasia (CIN), (b) high-risk HPV type, (c) clearance/persistence of high-risk HPV, and (d) disease outcome in women participating in a multicenter follow-up study in three New Independent States countries. Totally, 232 biopsy samples tested high-risk HPV-positive and/or Papanicolaou smear-positive women were immunohistochemically stained for the following cell cycle markers: p105, p107, p130, E2F4, p21(CIP1/WAF1/SDI1), cyclin A, and Ki-67. In addition, apoptotic index (AI) and mitotic index (MI) were determined in H&E-stained sections. Prospective follow-up data were available to disclose the clinical and virological outcome of the lesions. The expression of Ki-67, p21(CIP1/WAF1/SDI1), and cyclin A and AI and MI values were markedly increased in high-grade lesions, but only MI was an independent predictor of CIN3 in multivariate analysis. Cyclin A was the only independent predictor of high-risk HPV (odds ratio, 1.09; 95% confidence interval, 1.01-1.18; P = 0.021), exceeding the predictive power of CIN grade and high-grade squamous intraepithelial lesion Papanicolaou smears. None of these markers provided any useful predictive information as to the clinical and virological outcomes during the follow-up. Highly significant correlations (P = 0.0001) were found between AI and MI as well as between MI and cyclin A, Ki-67 and p21(CIP1/WAF1/SDI1), Ki-67 and cyclin A, and p21(CIP1/WAF1/SDI1) and cyclin A followed by that between p105 and cyclin A (P = 0.001) and p105 and p130 (P = 0.002). All tested factors related to cell cycle were increased, but only MI and cyclin A was an independent predictor of CIN3 and high-risk HPV carriage, respectively.
    Cancer Epidemiology Biomarkers &amp Prevention 07/2006; 15(7):1250-6. · 4.56 Impact Factor
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    ABSTRACT: Oral contraception (OC) has been proclaimed by the IARC as a risk factor of cervical cancer (CC), on prolonged use by high-risk human papillomavirus (HPV) positive women. However, the available data are far from complete, and more evidence is necessary on the potential confounding effects of sexual behavior and HPV infection. The aim of the present was study to analyse the risk estimates for OC users in order to develop several intermediate end-point markers in cervical carcinogenesis. A cohort of 3,187 women, enrolled in a multi-center screening trial in three New Independent States (NIS) of the former Soviet Union (the NIS Cohort Study), was stratified into three groups according to their contraception modes: i) non-users of contraception, ii) non-OC users and iii) OC users. These groups were analysed forpredictors of three outcome measures: a) exposure to HR-HPV; b) progression to high-grade cervical intraepithelial neoplasia (CIN2/3 and HSIL); and c) persistence/clearance of HR-HPV and cytological abnormalities during a prospective follow-up. All three groups had an identical prevalence of HR-HPV (HCII and PCR), Pap smear abnormalities and CIN histology, but differed significantly (p=0.0001) with regard to all key variables of sexual behaviour, known as risk factors for CC. Predictors of HR-HPV, CIN2/3 and HSIL were different in the three groups, reflecting these different sexual preferences. Use of OC was not a significant predictor of CIN2/3 or HSIL in HPV-positive or HPV-negative women. Outcomes of cervical disease and HR-HPV infection were unrelated to contraception. In a multivariate regression model mode of contraception was of no predictive value for either HR-HPV or high-grade CIN. Sexual behaviour is different among OC users, non-OC users and in nonusers of contraception; these risk factors predispose women to HR-HPV, high-grade CIN, and determine the outcome of their cervical disease/HR-HPV infection. The use of OC is not an independent risk factor for any of these intermediate end-point markers of cervical carcinogenesis. Failure to record these epidemiological data inevitably leads to erroneous conclusions about the role of OC as an independent risk factor of cervical cancer.
    Anticancer research 01/2006; 26(6C):4729-40. · 1.71 Impact Factor
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    ABSTRACT: We analysed the temporal relationships of the clearance of human papillomavirus (HPV) DNA and cytological abnormalities in women participating in a screening study in three NIS countries. The 274 patients included in this analysis were prospectively followed-up for 21.6 months (range: 0.5-42.9). All 274 women had abnormal PAP test (ASC-US or higher) and high-risk HPV-positive test (HCII) at baseline. Two groups were compared: 132 women who cleared both tests (Group 1), and 142 women who cleared either HPV or abnormal PAP test (Group 2). The first clearance during the follow-up, and the last visit clearance were modeled using life-table techniques, and the predictive factors were analysed using univariate (Kaplan-Meier) and multivariate (Cox) survival analysis. There was no difference in the mean clearance time for the abnormal PAP test (14.4 months; 0.7-40.5 and 12.6 months; 0.5-35.0) and high-risk HPV DNA (12.67 months; 0.6-33.5 and 10.8 months; 0.7-33.4) in Group 1 and Group 2 (Mann-Whitney: P = 0.107 and P = 0.082, respectively). Clearance times for HPV DNA and abnormal PAP test did not deviate from each other in either groups (Wilcoxon: P = 0.063 and P = 0.088). The monthly clearance rates for the abnormal PAP test are 1.32 and 1.38%, and those for the HPV DNA 1.62 and 1.61%, in Groups 1 and 2, respectively. Of the factors predicting the last visit clearance, the issues related to smoking are of particular interest. The clearance of high-risk HPV type and abnormal PAP test shows a close temporal relationship, the former preceding the latter, however, by an interval of 1.0-2.0 months.
    European Journal of Obstetrics & Gynecology and Reproductive Biology 05/2005; 119(2):219-27. · 1.84 Impact Factor
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    ABSTRACT: We completed an analysis of the factors predicting the persistence of high risk (HR) HPV infections in women participating in a multicenter screening trial in three NIS countries. The 543 baseline HR HPV-positive women included in this analysis are derived from a sub-cohort of 887 women who were prospectively followed-up for a mean of 21.6 months (range: 0.5-42.9) as a part of a multi-center screening study in three NIS countries (the NIS cohort study; n = 3,187 women). Of these 543 women, 273 showed persistent HR-HPV in serial Hybrid Capture II (HCII) testing during the follow-up (Group 1), whereas 270 women cleared their infection (Group 2). These two groups were compared with their epidemiological, clinical, and virological data (HCII, PCR) to disclose the factors predicting persistent HR-HPV infection. Women with persistent HR-HPV infections were significantly younger (27.3 yrs) than those who cleared their infection (29.1 yrs) (p = 0.006), and their follow-up time was shorter; 14.1 and 21 months, respectively (p = 0.0001). Both variables were treated as confounders in the multivariate analyses. Of the 66 recorded epidemiological variables, only being a current smoker proved to be an independent predictor (OR 1.693; 95% CI 1.114-2.573; p=0.014). Baseline colposcopy, biopsy or Pap smear did not predict HPV persistence, whereas an incident or persistent abnormal Pap during the follow-up were independent predictors in a multivariate model (p = 0.005), together with the high viral load (HCII RLU/CO at 100 pg/ml cut-off), and HR HPV positive PCR test (p = 0.0001). When all significant variables were entered in the regression model, only the follow-up time (OR 0.950, 95% CI 0.924-0.976; p = 0.0001) and HR-HPV positive PCR (OR 4.169, 95% CI 1.741-9.987; p = 0.001), remained independent predictors. While several factors were related to HR-HPV persistence in univariate analysis and when adjusted for age and follow-up time as confounders, the only independent predictors in the multivariate regression model were follow-up time and HR-HPV positive PCR. Clearly more data are needed on type-specific persistence and HPV integration as its predictors.
    European journal of gynaecological oncology 02/2005; 26(5):491-8. · 0.58 Impact Factor
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    ABSTRACT: The recognition of high-risk human papillomaviruses (HPVs) as etiological agents of cervical cancer has increased the demands to use testing for HPV for the detection of abnormal cervical smears and for cervical cancer screening. The present study compared the performance of the Hybrid Capture 2 (HC2) assay with that of PCR for the detection of significant cervical lesions in 1,511 women with different risks for HPV infections in three New Independent States of the former Soviet Union. The results showed that the level of agreement between the HC2 assay and PCR was substantial, with a kappa (Cohen) value of 0.669 (95% confidence interval [CI], 0.629 to 0.709). Of the 228 samples with discrepant results, 92 were positive by the HC2 assay but negative by PCR, whereas 136 samples were PCR positive but HC2 assay negative. The positive predictive values (PPVs) of the HC2 assay and PCR in detecting high-grade intraepithelial lesions (HSILs) were 4.5% (95% CI, 3.5 to 5.5%) and 3.6% (95% CI, 2.7 to 4.5%), respectively, and the negative predictive values (NPVs) were 99.6% (95% CI, 99.3 to 99.9%) and 99.3% (95% CI, 98.9 to 99.7%), respectively. The sensitivities of the HC2 assay and PCR for the detection of HSILs were 85.2 and 74.0%, respectively, and the specificities were 67.2 and 64.1%, respectively. In receiver operating characteristic (ROC) analysis, the performance of the HC2 assay for the detection of HSILs was excellent (P = 0.0001); the area under the ROC analysis curve was 0.858 (95% CI, 0.811 to 0.905), and the optimal balance between sensitivity (86.5%) and specificity (80%) was obtained with an HC2 assay cutoff level of 15.6 relative light units/positive control. Use of this cutoff would increase the specificity of the HC2 assay to 80.0% without compromising sensitivity. In conclusion, the results of PCR and the HC2 assay were concordant for 85% of samples, resulting in substantial reproducibility. Both tests had low PPVs, equal specificities, and equal (almost 100%) NPVs for the detection of HSILs; but the sensitivity of the HC2 assay was slightly better.
    Journal of Clinical Microbiology 07/2004; 42(6):2470-5. · 4.07 Impact Factor
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    ABSTRACT: The rates of acquisition and the times of incident high-risk (HR) human papillomavirus (HPV) infections and Pap smear abnormalities and their predictive factors were analyzed in women participating in a multicenter screening study in three countries of the New Independent States of the former Soviet Union. The 423 patients were prospectively monitored for a mean of 21.6 months. At the baseline, 118 women were HR HPV DNA negative (Hybrid Capture II assay) and Pap smear negative (group 1), 184 were HPV DNA positive and Pap smear negative (group 2), and 121 were HPV DNA negative and Pap smear positive (group 3). The time to the acquisition of an incident abnormal Pap smear (19.4 months) was significantly longer in group 1 than in group 2 (9.2 months) (P = 0.0001). The times of acquisition of incident HR HPV infection were 16.6 and 11.0 months in group 1 and group 3, respectively (P = 0.006). The monthly rates of acquisition of incident HR HPV infections were very similar in group 1 (1.0%) and group 3 (0.8%), whereas the rate of acquisition of an abnormal Pap smear was significantly higher in group 2 (3.1%) than in group 1 (1.5%) (P = 0.0001). The acquisition of HR HPV infection (but not a positive Pap smear result) was significantly (P = 0.0001) age dependent. The only significant independent (P = 0.001) predictor of the incidence of an abnormal Pap smear result was a high HR HPV load of >20 relative light units/control value (CO) (rate ratio, 2.050; 95% confidence interval, 1.343 to 3.129). Independent predictors of incident HR HPV infection were patient category (a sexually transmitted disease) and ever having been pregnant. The time of acquisition of HR HPV infection was 3 months shorter than that of an abnormal Pap smear. At the baseline the high load of a particular HR HPV type is the single most important predictor of an incident Pap smear abnormality, whereas young age and having a sexually transmitted disease predict incident HR HPV infections.
    Journal of Clinical Microbiology 03/2004; 42(2):505-11. · 4.07 Impact Factor
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    ABSTRACT: Human papillomavirus (HPV) infection is a sexually transmitted disease (STD) and the single most important etiological agent of cervical cancer. In parallel with the increase of STDs and because of the lack of any organized cancer screening in the new independent states of the former Soviet Union, the incidence and mortality rates of cervical cancer are rapidly rising. This is the first report from an ongoing European Commission-funded (INCO-Copernicus Program) cross-sectional and cohort study (focused on the key issues of this major health problem in the new independent states) analyzing the performance of the HPV DNA (Hybrid Capture II) test as a potential screening tool for cervical cancer in these countries. A series of 3,175 women (screening, gynecological, or STD patients) from six clinics in Russia, Belarus, and Latvia received routine cytology and HPV testing with Hybrid Capture II (HCII). All women with HPV-positive results or abnormalities in cytology were subjected to colposcopy and biopsy. The sensitivity, specificity, receiver operating characteristics, as well as positive (PPV) and negative predicting values (NPV), were determined for HCII and quality-controlled cytology in detecting significant pathology (cervical intraepithelial neoplasia [CIN] 3 and cancer). Significant pathology was strongly associated with high-grade cytology (odds ratio [OR] = 8.5; 95% confidence interval [CI] = 4.1-17.8; chi-square, p < .0001). Pap smear cytology detected high-grade lesions with a sensitivity of 64.0% (44.8-83.2), specificity of 89.1% (84.5-93.7), PPV of 44.4% (28.8-61.0), and NPV of 94.8% (91.2-98.4). Of the 3,086 samples analyzed by HCII, 33.0% were positive for oncogenic HPV types, with a wide variation (from 23% to 45%) between the three patient groups (p < .0001). The presence of high-grade cytology was significantly associated with HCII positivity at all cutoff levels (OR = 14.4; 95% CI = 8.4-24.5; chi-square, p < .0001; 1 pg/mL threshold). In the receiver operating characteristics curve, the HCII cutoff point most closely balancing sensitivity (83.1%) and specificity (75.6%) was 2 pg/mL. The presence of high-grade histology was associated with HCII positivity (cutoff 1 pg/mL; OR = 4.8; 95% CI = 0.7-34.2;p = .047). At the cutoff (1 pg/mL), sensitivity of the HCII test was 96.6% (90.0-100), specificity was 15.9% (10.6-21.2), PPV was 15.1% (9.9-20.3), and NPV was 96.8% (90.3-100). Changing the cutoff significantly affected sensitivity at 20 pg/mL and NPV at 500 pg/mL. HCII assay is a sensitive tool in detecting significant pathology, but less specific than the Pap test. A negative HCII test practically precludes high-grade CIN (NPV, >95%). Because the performance characteristics of the HCII test depend on the prevalence of HPV and CIN in the study population, the cost-benefit issues in different settings will be the limiting factor for the application of this test as a screening tool.
    Journal of Lower Genital Tract Disease 05/2002; 6(2):97-110. · 1.21 Impact Factor
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    ABSTRACT: To assess impact on interlaboratory agreement of 2 optional modes to convert Papanicolaou classification to Bethesda System (TBS) and demonstrate effect of verification bias correction on test performance in the New Independent States of the former Soviet Union (NIS) cohort study. Conventional Pap smears were classified in NIS laboratories and rescreened in a reference center (RC) using modified Papanicolaou classification. Two optional methods (TBS1, TBS2) were used to convert original classification to TBS. All classifications were tested for interlaboratory agreement and performance indicators with and without verification bias correction. Interlaboratory agreement of original classification was fair with regular kappa, but substantial with weighted kappa. TBS1 option (Class 2 in atypical squamous cells of undetermined significance [ASCUS]) did not remedy this limited reproducibility. When Class 2+ (borderline dyskaryosis) was used as cutoff for ASCUS (TBS2), interlaboratory agreement was upgraded to moderate and almost perfect. Test performance was significantly different between NIS and RC only for TBS1 option with ASCUS cutoff RC showing better sensitivity/specificity balance by area under receiver operating characteristic curve test. In converting traditional classification to TBS, selection of appropriate equivalents to TBS categories has a major impact on interlaboratory agreement and performance indicators.
    Acta cytologica 53(5):548-57. · 0.69 Impact Factor