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.

Hybrid capture II and polymerase chain reaction for identifying HPV infections in samples collected in a new collection medium: a comparison.

OBJECTIVE: To compare the performance of human papillomavirus (HPV) DNA detection by polymerase chain reaction (PCR) and Hybrid Capture II (HCII) test (Digene, Gaithersburg, Maryland, U.S.A.) in residual cells left in the collection vials of the DNACitoliq system (Digene Brasil, São Paulo, Brazil). STUDY DESIGN: A series of 263 cervical samples collected for liquid-based cytology with the DNACitoliq system was tested for oncogenic HPV types first with HCII and subsequently with PCR. After DNA purification with GFX Genomic Blood DNA Purification Kit (Amersham, Piscataway, New Jersey, U.S.A.), PCR was performed using AmpliTaq Gold DNA polymerase (Applied Biosystems). PGMY09/11 L1 consensus primers and GH20/PCO4 primers for human beta-globin target were coamplified. RESULTS: Altogether, 260 samples were positive for beta-globin, and 3 negative ones were excluded from the analysis. PCR and HCII yielded concordant results in 199 cases (76.5%) (102 positive and 97 negative), with Cohen's kappa of .577 (95% CI .477-.677) and weighted kappa of .733 (95% CI .659-.791). HPV prevalence in different categories of cytologic abnormalities was practically identical with HCII and PCR assays (P=.989). Among the 61 (23.5%) discrepant cases, 28 samples were HCII+/PCR- cases. Of these, 27 of 28 samples showed a low viral load, and 1 had an intermediate viral load. CONCLUSION: The data suggest that residual material from the DNACitoliq system adequately preserves HPV DNA for detection by HCII and PCR, with performance similar to that of specimen transport medium.

Low and high-risk HPV types detected with hybrid capture II - HC2 - in liquid-based cytology - DNA Citoliq System: experience from the LAMS - Latin American Screening study

Avalia a performance do meio UCM - Universal Collecting Médium - do novo sistema DNACITOLIQ - Digene-Brasil - para citologia de base líquida e ensaios biomoleculares em uma população geral submetida a ratreio de rotina para lesões de colo uterino associadas ao HPV de baixo e alto riscos