Type-specific persistence of high-risk human papillomavirus infections in the New Independent States of the former Soviet Union Cohort Study.

BACKGROUND: Prospective follow-up studies have recently suggested that persistent high-risk human papillomavirus (HPV) infections play a key role in the progression of CIN lesions and in the development of cervical cancer. However, data on type-specific persistence, viral integration, and the role of multiple infections are scanty. MATERIALS AND METHODS: A cross-sectional/cohort study was conducted between 1998 and 2002 in three New Independent States of the former Soviet Union comprising a cohort of 3,187 women, of whom 854 women were followed up for a mean of 17 months (SD, 11.6). HPV genotyping was done with real-time PCR, detecting HPV types 16, 18/45, 31, 33/52/58, 35, and 39. The integration status of HPV16 was examined by using a novel Taqman-based PCR method. RESULTS: The mean clearance time for the individual high- risk-type infection was 16.5 months (range = 0.9-34.9 months). HPV16 and HPV31 were the most persistent infections (clearance times = 18.1 and 16.2 months, respectively), whereas HPV39 infections cleared most rapidly. The mean copies per cell in HPV18/45, HPV31, HPV33/52/58, and HPV39 infections were higher in persisting HPV infections than in HPV infections that cleared, but the difference was not significant. Integration of HPV16 was not found to correlate with HPV persistence. CONCLUSIONS: A large proportion of women remained high-risk HPV positive after 18 months. Coinfection with multiple HPV types, viral load, or integration status did not correlate with persistence of high-risk HPV infections.

Prevalence of the most common high-risk HPV genotypes among women in three new independent states of the former Soviet Union.

Type distribution of HPV has been studied in different geographic regions, but the data are scanty from the new independent states of the former Soviet Union. Here the HPV prevalence and distribution of the most frequent high-risk HPV types among 3,187 women at different risk for HPV and cervical intraepithelial neoplasia in Russia, Belarus, and Latvia is reported. HPV detection, type distribution and viral load analysis in DNA samples from cervical scrapes were done with real-time PCR-based assay detecting HPV types 16, 18, 31, 33, 35, 39, 45, 52, and 58. The overall HPV prevalence was 31.2%, HPV16 was the most prevalent type followed by HPV31 and HPV33 group. The overall HPV prevalences in Russia, Belarus and Latvia were 33.4%, 27.5%, and 26.2%. The type distributions were similar in these countries, except for Latvia where HPV39 was the third prevalent genotype. HPV prevalence was highest (40.8%) among women from sexually transmitted disease clinic, followed by 30.9% among gynecological outpatients and 27.2% in screening patients. HPV detection increased with cytological abnormality (P = 0.0001) and lesion grade in the biopsy (P = 0.0001), from 27% to 72% in normal samples to cancer, and from 64% to 77% in cervical intraepithelial neoplasia 1 to cancer. The normalized viral loads varied greatly between and among different HPV-types. The mean log HPV33 group copies/cell increased from negative for intraepithelial lesions to cancer (P = 0.049). Distribution of the most common high-risk HPV-types seems to be similar in these countries as reported in other major geographical regions.

Human papillomavirus testing and conventional pap smear cytology as optional screening tools of women at different risks for cervical cancer in the countries of the former soviet union.

OBJECTIVES: 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. MATERIALS AND METHODS: 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). RESULTS: 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. CONCLUSIONS: 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.