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Evaluation of visual inspection with acetic acid (VIA), Lugol's iodine (VILI), cervical cytology and HPV testing as cervical screening tools in Latin America: This report refers to partial results from the LAMS (Latin AMerican Screening) study

Objectives: To assess the performance indicators of visual inspection with acetic acid (VIA) and visual inspection with Lugols iodine (VILI) in four Latin American centres participating in the ongoing Latin AMerican Screening (LAMS) study, in settings with moderate incidence of cervical disease and with poorly to moderately well-organized cervical cancer screening. Setting: Three Brazilian centres (São Paulo, Campinas and Porto Alegre) and one Argentine centre (Buenos Aires) recruited a total of 11,834 healthy women to undergo VIA, VILI, conventional Pap smear and Hybrid Capture II (HCII). Methods: Women who had a positive result from any of these tests were subjected to colposcopy and biopsies (if necessary), and women with high-grade cervical intraepithelial neoplasia (CIN) were properly treated. To control for verification bias, 5% of women with normal tests were referred for colposcopy, as were 20% of HCII-negative women. Results: Data on VIA (n=11,834), VILI (n=2994), conventional Pap smear (n=10,138) and HCII (n=4195) were available for test comparisons, calculating sensitivity, specificity, and positive and negative predictive values. Overall test positivity was 11.6% for VIA, 23.0% for VILI, 2.2% for Pap smear (LSIL threshold), 1.1% for Pap smear (HSIL threshold) and 17.1% for HCII. VIA was positive in 61.8% of the women with CIN 1, 57.0% of those with CIN 2, 35.0% of women with CIN 3 and in 21 of 28 (75%) of women with cancer. Approximately 10% of women with no detectable disease had an abnormal VIA. Regarding VILI, 83.3% of women diagnosed with CIN 1 and 62.5% of those with CIN 3 had an abnormal test. VILI failed to detect one of three cases of cancer. Both the sensitivity, specificity and positive predictive value of VIA and VILI in detecting CIN 2 or CIN 3 could be significantly improved depending on the combination with Pap smear or HCII (sensitivity up to 100.0% and specificity up to 99.8%). Conclusions: The LAMS study failed to reproduce the performance figures obtained with VIA and VILI (as stand-alone tests) in some other settings, where the prevalence of cervical disease was higher. However, a combined use of VIA or VILI with the Pap test or HCII allowed specific detection of cervical abnormalities.

Rastreamento anterior para câncer de colo uterino em mulheres com alterações citológicas ou histológicas

OBJETIVO: Analisar a historia de rastreamento citologico anterior em mulheres que apresentaram alteracoes citologicas e confirmacao histologica para câncer cervical. METODOS: Estudo transversal com 5.485 mulheres (15-65 anos) que se submeteram a rastreamento para o câncer cervical entre fevereiro de 2002 a marco de 2003, em Sao Paulo e Campinas, SP. Aplicou-se questionario comportamental e foi feita a coleta da citologia oncologica convencional ou em base liquida. Para as participantes com alteracoes citologicas indicou-se colposcopia e, nos casos anormais, procedeu-se a biopsia cervical. Para investigar a associacao entre as variaveis qualitativas e o resultado da citologia, utilizou-se o teste de qui-quadrado de Pearson com nivel de significância de 5%. RESULTADOS: Dentre os resultados citologicos, 354 (6,4%) foram anormais, detectando-se 41 lesoes intra-epitelial escamosa de alto grau e tres carcinomas; em 92,6% revelaram-se normais. De 289 colposcopias realizadas, 145 (50,2%) apresentaram alteracoes. Dentre as biopsias cervicais foram encontrados 14 casos de neoplasia intra-epitelial cervical grau 3 e quatro carcinomas. Referiram ter realizado exame citologico previo: 100% das mulheres com citologia compativel com carcinoma, 97,6% das que apresentaram lesoes intra-epiteliais de alto grau, 100% daquelas com confirmacao histologica de carcinoma cervical, e 92,9% das mulheres com neoplasia intra-epitelial cervical grau 3. A realizacao de citologia anterior em periodo inferior a tres anos foi referida, respectivamente, por 86,5% e 92,8% dessas participantes com alteracoes citologicas e histologicas. CONCLUSOES: Entre as mulheres que apresentaram confirmacao histologica de neoplasia intra-epitelial cervical grau 3 ou carcinoma e aquelas que nao apresentaram alteracoes histologicas nao houve diferenca estatisticamente significante do numero de exames citologicos realizados, bem como o tempo do ultimo exame citologico anterior.

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.

Drug addiction is not an independent risk factor for oncogenic human papillomavirus infections or high-grade cervical intraepithelial neoplasia: case-control study nested within the Latin American Screening study cohort

Drug abuse (addiction) has been listed among the risk factors for human papillomavirus (HPV) infections, but no case-control studies exist to rule out sexual behaviour and other potential confounders. The aim of this study is to evaluate the role of drug addiction as an independent predictor of HR-HPV infections and (cervical intraepithelial neoplasia) CIN2+ in an age-matched case-control (1:4) study nested within the prospective Latin American Screening (LAMS) study cohort. All 109 women in the LAMS cohort (n = 12,114) reporting drug abuse/addiction were matched with four controls (n = 436) of non-abusers strictly by age. Conditional logistic regression analysis was used to estimate the co-variates of drug abuse, and the whole series (n = 545) was analysed for predictors of HR-HPV and CIN2+ using univariate and multivariate regression models. Oncogenic HPV infections were significantly (P = 0.019) more prevalent among abusers (37.7%) than in controls (21.9%), but there was no difference in high-grade squamous intraepithelial lesions (P = 0.180) or CIN2+ lesions (P = 0.201). In multivariate conditional logistic regression, number of lifetime sexual partners (P = 0.0001), ever smokers (P = 0.0001), non-use of OCs (P = 0.013), ever having sexually transmitted diseases (STD) (P = 0.041) and no previous Pap smear (P = 0.027) were independent co-variates of drug addiction. Drug abuse was not an independent risk factor of high-risk (HR)-HPV infection, which was significantly predicted by (1) age below 30 years (P = 0.045), (2) more than five lifetime sexual partners (P = 0.046) and (3) being current smoker (P = 0.0001). In multivariate model, only HR-HPV infection was an independent risk factor of CIN2+ (P = 0.031), with adjusted OR = 11.33 (95% CI 1.25–102.50). These data indicate that drug addiction is not an independent risk factor of either HR-HPV infections or CIN2+, but the increased prevalence of HR-HPV infections is explained by the high-risk sexual behaviour and smoking habits of these women.

Safety of screening with Human papillomavirus testing for cervical cancer at three-year intervals in a high-risk population: experience from the LAMS study*

Objectives To assess whether human papillomavirus (HPV) testing is a safe enough approach to warrant extension of the screening intervals of baseline Papanicolaou (Pap)−/HPV− women in low-income settings. Methods Of the >1000 women prospectively followed up as part of the Latin American Screening (LAMS) Study in São Paulo, Campinas, Porto Alegre) and Buenos Aires, 470 women with both baseline cytology and Hybrid Capture 2 (HC2) results available were included in this analysis. These baseline Pap-negative and HC2− or HC2+ women were controlled at six-month intervals with colposcopy, HC2 and Pap to assess the cumulative risk of incident Pap smear abnormalities and their predictive factors. Results Of the 470 women, 324 (68.9%) were high-risk HPV (hrHPV) positive and 146 (31.1%) were negative. Having two or more lifetime sex partners (odds ratio [OR] = 2.63; 95% CI 1.70–3.51) and women using hormonal contraception (OR = 2.21; 95% CI 1.40–3.51) were at increased risk for baseline hrHPV infection. Baseline hrHPV+ women had a significantly increased risk of incident abnormal Pap smears during the follow-up. Survival curves deviate from each other starting at month 24 onwards, when hrHPV+ women start rapidly accumulating incident Pap smear abnormalities, including atypical squamous cells (ASC) or worse (log-rank; P < 0.001), low-grade squamous intraepithelial lesions (LSIL) or worse (P < 0.001) and high-grade squamous intraepithelial lesions (HSIL) (P = 0.03). Among the baseline hrHPV− women, the acquisition of incident hrHPV during the follow-up period significantly increased the risk of incident cytological abnormalities (hazard ratio = 3.5; 95% CI 1.1–11.7). Conclusion These data implicate that HPV testing for hrHPV types might be a safe enough approach to warrant extension of the screening interval of hrHPV−/Pap−women even in low-resource settings. Although some women will inevitably contract hrHPV, the process to develop HSIL will be long enough to enable their detection at the next screening round (e.g. after three years).

Expression of p16INK4a and cervical infection with high-risk human papillomavirus are not related to p53 activity in cervical intraepithelial neoplasia

The objective of the study was to investigate the expression of p53 and p16INK4a in cervical intraepithelial neoplasia (CIN) and their relation with disease severity and high-risk human papillomavirus (HR-HPV) status. A series of 125 women with previous positive Pap smear were selected for this cross-sectional study. All patients underwent gynecological examination, including colposcopy. Specimens for Pap smears, Hybrid Capture 2 (HC2) test, and pathologic analysis were obtained. After evaluation of CIN grade, immunohistochemical detection of proteins p53 and p16INK4a was performed on paraffin-embedded sections. The extent of immunoexpression of both proteins was analyzed in relation to CIN grade and HR-HPV status. CIN was graded as 1 in 21, 2 in 17, and 3 in 87 specimens. p16INK4a positivity (at least 5% of epithelial cells stained) was found in 99 of 125 cases (79.2%) and was significantly higher in high-grade lesions as compared to low-grade CIN (P< 0.001). The expression of p53 did not differ across histologic strata. Protein expression neither of p16INK4a nor of p53 correlated with HR-HPV status. Expression of p16INK4a was not related with that of p53. Our study gives further support to previous findings of strong association of p16INK4a immunostaining with severity of epithelial atypia, but this protein may not be considered a predictor of HR-HPV status determined with HC2. By contrast, immunoexpression of p53 was related neither to CIN grade nor to HR-HPV status.

Co-factors of high-risk human papillomavirus infections display unique profiles in incident CIN1, CIN2 and CIN3

In addition to oncogenic ‘high-risk’ human papillomaviruses (HR-HPV), several co-factors are needed in cervical carcinogenesis, but it is poorly understood whether these HPV co-factors associated with incident cervical intraepithelial neoplasia (CIN) grade 1 are different from those required for progression to CIN2 and CIN3. To gain further insights into the true biological differences between CIN1, CIN2 and CIN3, we assessed HPV co-factors increasing the risk of incident CIN1, CIN2 and CIN3. Data from the New Independent States of the Former Soviet Union (NIS) Cohort (n = 3187) and the Latin American Screening (LAMS) Study (n = 12,114) were combined, and co-factors associated with progression to CIN1, CIN2 and CIN3 were analysed using multinomial logistic regression models with all covariates recorded at baseline. HR-HPV-positive women (n = 1105) represented a subcohort of all 1865 women prospectively followed up in both studies. Altogether, 90 (4.8%), 39 (2.1%) and 14 (1.4%) cases progressed to CIN1, CIN2 and CIN3, respectively. Baseline HR-HPV was the single most powerful predictor of incident CIN1, CIN2 and CIN3. When controlled for residual HPV confounding by analysing HR-HPV-positive women only, the risk profiles of incident CIN1, CIN2 and CIN3 were unique. Completely different HPV co-factors were associated with progression to CIN1, CIN2 and CIN3 in univariate and multivariate analyses, irrespective of whether non-progression, CIN1 or CIN2 was used as the reference outcome. HPV co-factors associated with progression to CIN1, CIN2 and CIN3 display unique profiles, implicating genuine biological differences between the three CIN grades, which prompts us to re-visit the concept of combining CIN2 with CIN3 or CIN1.

Aided visual inspection with acetic acid (VIA) and hpv detection as optional screening tools for cervical cancer and its precursor lesions

PURPOSE OF INVESTIGATION To assess the contribution of visual inspection with acetic acid (VIA) and Hybrid Capture II (HCII) as adjunct methods to the Pap test in detecting cervical neoplasia. SUBJECTS AND METHODS This was a cross-sectional study with 809 women who consecutively attended gynecological consultations at Campinas University, Brazil, from January 2002 to July 2003. Pap test, HCII, VIA, and colposcopy were offered to all patients. Performance of tests (alone or in combination) in detecting histologically confirmed lesions was evaluated. RESULTS Of the 40 patients with CIN, 69% had CIN1, 26% CIN2 or CIN3 and one patient had invasive carcinoma. VIA had the best performance in detecting CIN, yielding 72% sensitivity and 91% specificity. Considering only CIN2 or worse as significant lesions, HCII had the best sensitivity (73%), while the Pap test was the most specific (93%). Combining the three exams, 92% of the CIN1 or worse were detected. When CIN1 was excluded from the analysis, Pap smear plus HCII delivered 82% sensitivity and 79% specificity. However, this combination yielded a very low (5%) PPV. CONCLUSION VIA and HCII contributed to the screening of cervical neoplasia in a group of Brazilian women, but the cost-effectiveness of conjoint screening modalities is still debatable.