Whole, Turret and step methods of rapid rescreening: is there any difference in performance?

We compared the performance of the Whole, Turret and Step techniques of 100% rapid rescreening (RR) in detection of false-negatives in cervical cytology. We tested RR performance with cytologists trained and among those without training. We revised 1,000 consecutive slides from women participating in an ongoing international screening trial. Two teams of experienced cytologists performed the RR techniques: one trained in RR procedures and the other not trained. The sensitivities in the trained group were Whole 46.6%, Turret 47.4% and Step 50.9%; and in the non-trained group were 38.6, 31.6 and 47.4%, respectively. The kappa coefficient showed a weak agreement between the two groups of cytologists and between the three RR techniques. The RR techniques are more valuable if used by trained cytologists. In the trained group, we did not observe significant differences between the RR techniques used, whereas in the non-trained group, the Step technique had the best sensitivity.

Pero Vaz de Caminha: an-interchange program for quality control between Brazil and Portugal

OBJECTIVE

To start an interexchange program for quality control in cervical cytology and discuss conceptual criteria for diagnosis.

STUDY DESIGN

Slides were selected in the archives of the 2 institutes and included cases with unsatisfactory, negative and positive results. Sets of slides were changed between the partners every 3 months. At the end of each year a senior cytopathologist was invited to discuss the major discrepancies found in the study.

RESULTS

A total of 1,041 cases were analyzed. Full concordance was obtained in 74.4% (774) of cases and discrepancies in 25.6% (267 cases). Full agreement was achieved in 276 (39%) of 707 cases categorized as negative. In 421 negative cases from laboratory A, this concordance represents 65.5% and 96.5% for laboratory B, which submitted 286 negative cases. The main discordance was the high number of atypical squamous cells of undetermined significance cases: 3.1% for A and 128 (33.2%) for B. Samples with discrepancies related to the quality of the material was another controversial issue: of 16 cases from laboratory A, 6 (37.5%) unsatisfactory cases were the same and 10 (62.5%) different. Laboratory B presented 20 unsatisfactory cases, and 14 (70.0%) had other diagnoses. Low grade squamous intraepithelial lesion and high grade squamous intraepithelial lesion concordance ranged from 75% to 80%, and invasive carcinoma has 4 discordances (28.5%), 3 previously screened as high grade squamous intraepithelial lesion and 1 as atypical squamous cells of undetermined significance. The kappa value obtained was 0.65, indicating substantial agreement.

CONCLUSION

Our results indicated that atypical squamous cells of undetermined significance diagnoses are the crucial point of controversies and concern the quality of routine diagnosis in cytopathology.

Screening for Cervical Cancer in High-Risk Populations: DNA Pap Test or Hybrid Capture II Test Alone?

This study was designed to evaluate whether Hybrid Capture II (HC2) test alone refer women to colposcopy as appropriately as DNA Papanicolaou (Pap) test, in the context of a high-risk group of women using the recently validated DNACitoliq LBC system. Women with suspected cervical disease were included in this cross-sectional study at a tertiary center in São Paulo, Brazil, for further workup. All women had cervical material collected for LBC and HC2 for high-risk human papillomavirus (hrHPV)-DNA test. Irrespective of cytology and HC2 results, colposcopy, and cervical biopsy when applicable, was systematically performed. All tests were performed blindly. Sensitivity, specificity, positive and negative predictive values, and overall accuracy of both methods were computed in relation to histology. A total of 1,080 women were included: 36.4% (393/1080) had ACUS+, 10.2% (110/1080) were high-grade squamous intraepithelial lesions (HSIL) or cancer. Mean age was 33.5 years. All women underwent colposcopy, and cervical biopsies were performed in 38.4% (415/1080): 33% (137/415) of the biopsies were negative, 14.4% (155/415) were low-grade squamous intraepithelial lesions (LSIL), 10.7% (116/415) were HSIL, and 0.6% (7/415) were cancer. HC2 sensitivity to diagnose biopsy-proven HSIL was 100%. Because all HSIL cases had a positive HC2 test, sensitivity could not be improved by adding LBC. Specificity and positive and negative predictive values of DNA Pap were not significantly different from HC2 test alone when considering LSIL+ histology as "gold standard" and HSIL+ histology. As a screening strategy for women with high-risk for cervical cancer, DNA Pap test does not seem to add substantially to HC2 alone in terms of appropriately referring to colposcopy.

100% rapid rescreening for quality assurance in a quality control program in a public health cytologic laboratory

OBJECTIVE

To verij5 the efficacy of the quality control (QC) program in a cytologic laboratwy with a rapid rescreening (RR) protocol.

STUDY DESIGN

RR, according to the Turret RR method, of all samples initially screened as negative at the Laboratory of Cytology, Adolfo Lutz Institute, was performed. The slides were reviewed for 60 seconds. Suspect smears were fully checked by 2 reviewers to determine the final diagnoses. A total of 2954 sequential cytologic results were considered in this study. Of the 2954, 2568 (86.9%) were considered initially negative according to our internal QC, and these cases underwent RR. Also, 10% were randomly selected from these negative cases for full reviewing. The internal QC in our laboratory includes review of cases selected according to clinical and cytomorphologic criteria.

RESULTS

Among the 2954 total cases, QC detected 386 (13%) atypias with final diagnoses reported according to The Bethesda System 2001 as follows: 82 (2.18%) low grade squamous intraepithelial lesions (LSILs), 35 (1.18%) high grade squamous intraepithelial lesions (HSILs), 2 (0.06%) squamous cell carcinomas, 105 (3.5%) atypical cells of undetermined significance (ASC-US), 4 (0.12%) atypical endocervical cells (AECs) and 158 (5.3%) unsatisfactory samples. RR of 2568 smears initially considered negative selected 194 (7.5%) slides. Of the 194, 146 (75.3%) were negative, 28 (14.4%) ASC-US, 5 (2.6%) AEC, 1 (0.5%) LSIL and 14 (7.2%) unsatisfactory. Full review of a 10% random fraction of the 2568 cases interpreted as negative did not detect lesions but did detect 5 (1.95%) unsatisfactory samples.

CONCLUSION

Internal QC used in our laboratory based on clinical and cytomorphologic criteria to select cases for review proved to be an efficient method of detecting HSIL and cervical cancer. The consensus basis of this program strongly limits the false positive and false negative rates and also provides subjects with continuing education. One hundred percent RR is more efficient than 10% full reviewing in detecting cervical abnormalities.

Molecular Strategies for Identifying Human Papillomavirus Infection in Routinely Processed Samples: Focus on Paraffin Sections

OBJECTIVE

To optimize the protocols of human papillomavirus (HPV) detection in clinical samples, we used polymerase chain reaction (PCR)-based techniques in paraffin-embedded tissue sections and compared the results with those obtained with PCR and Hybrid Capture II (HC2) performed in liquid-based cytology (LBC) preservation medium.

MATERIALS AND METHODS

Forty-five consecutive cervical biopsy specimens were taken from women participating in the ongoing Latin American Screening Study at Leonor Mendes de Barros Hospital, São Paulo, Brazil, during 2003 and 2004. The biopsy specimens were analyzed for HPV by a modified GP5+/GP6+ PCR protocol, and the results were compared with those obtained by PGMY PCR and HC2 in samples collected in LBC preservation medium.

RESULTS

beta-Globin was detected in 100% of the multiplex PCR system from LBC samples and 66.7% with PCO4+/PCO3+ PCR in biopsy specimens. Of the three methods, PGMY PCR system and HC2 were equally effective in detecting HPV; both detected 13 cases in 45 samples (28.9%). The GP5+/GP6+ PCR applied in biopsy specimens showed a 20% HPV detection rate (9/45).

CONCLUSIONS

Our PCR protocols worked reasonably well and allowed us to compare the three molecular methods with histological and cytological findings. The reproducibility of the results makes the technique applicable in archival materials.

Immunocytochemical expression of p16INK4A and Ki-67 in cytologically negative and equivocal pap smears positive for oncogenic human papillomavirus

This study was designed to analyze the cross-sectional comparison of the p16 and Ki-67 immunocytochemical expression in negative and equivocal (atypical squamous cells of undetermined significance (ASC-US)) liquid-based cytology (LBC) samples testing positive for high-risk human papillomavirus (HPV) types with HC2 assay or polymerase-chain reaction (PCR). A series of 199 consecutive LBC specimens derived from the same number of women participating in the ongoing Latin American Screening Study at Leonor Mendes de Barros Hospital, Sao Paulo, were analyzed using immunocytochemistry for expression of p16 and Ki-67 in negative and equivocal LBC samples testing positive for high-risk HPV types with hybrid capture II test (HC2) or PCR. All patients with at least one test positive (cytology, PCR, and/or HC2) were followed each 6 months for 3 years. The follow-up procedure consisted of visual examination, colposcopic inspection, cytology, and HC2 assay. Among the negative cytologic samples, 101 were HPV-positive and 55 HPV-negative. Of the HPV-positive group, 59 of 101 cases (58.4%) were positive for both p16 and Ki67 immunostaining, and 17 of 101 (16.8%) were negative for both. The proportion of Ki-67-positivity increased almost in parallel with the increasing grade of p16-positivity (p = 0.0001 for linear trend). In the HPV-negative group, both markers were negative in 41 of 55 cases (74.5%), and no statistical relationship was observed between the two markers (Pearson, p = 0.595). HPV-positive ASC-US samples demonstrated a simultaneous positive immunoreaction for p16 and Ki67 in 11 of 16 cases (68.7%), whereas 3 (18.7%) were concurrently negative. The relationship between the two markers was of borderline significance (Pearson, p = 0.053), but no linear relationship was found between the graded p16 and Ki-67 expression (p = 0.065 for linear trend). In the HPV-negative ASC-US group, there was no statistical association between the graded p16 and Ki-67 positivity (Pearson, p = 0.281). After 36 months of follow-up of the ASC-US patients, 6 women still displayed ASC-US smear, of which 4 of 6 were HPV-positive and expressed both p16 and Ki-67 markers. Two of 43 ASC-US smears had high-grade squamous intraepithelial lesions diagnosed (4.6%), and 1 had low-grade squamous intraepithelial lesion (2.3%). All of those were positive for HPV, p16 and Ki-67. Patients with ASC-US diagnosis and positive high-risk HPV status and positive for p16 Ki67 should be carefully observed to exclude occurrence of a squamous intraepithelial lesion. The combination of these two markers can be a useful implement for management of women with equivocal cytology.

DCS liquid-based system is more effective than conventional smears to diagnosis of cervical lesions

OBJECTIVE

To compare the performances of Papanicolaou test (PapTest) and of a new liquid-based cytology method, DNA-Citoliq System (DCS), in a high-risk population, with histology confirmation.

METHODS

Paired specimens of exfoliated cervical cells were collected under split-sample protocol. All patients were submitted to colposcopy and a biopsy taken when any atypical transformation zone was seen. Sensitivity, specificity, positive and negative predictive values, and overall accuracy of both conventional and DCS methods were computed in relation to histology.

RESULTS

A total of 1095 patients were analyzed by two cytology methods and, in 425 (38.8%), histologically. There were significantly more adequate samples with DCS (98.63%) than with conventional (89.6%) smears (P < 0.001). ASCUS was diagnosed significantly more with DCS than with conventional Pap (P < 0.001). Conventional Pap misclassified as normal 55.4% (158/285) of cases with either LSIL or HSIL or cancer at histology, whereas DCS misclassified 31.2% (89/285) of cases (P < 0.001). DCS had a significantly higher sensitivity (70% and 91.3%) than the conventional Pap (49.8% and 72.8%) to detect both LSIL+ and HSIL+ at histology, respectively. On the other hand, specificity of conventional smear (88.2% and 85.2%) was significantly higher than DCS (75.4% and 70.9%) considering both LSIL+ and HSIL+ at histology, respectively.

CONCLUSIONS

This study confirms the superiority of the liquid-based cytology system DCS to detect cervical lesions. The rate of adequate DSC slides was significantly higher than with conventional cytology.

High-risk HPV detection by Hybrid Capture and ploidy determination by a computer-assisted system in cervical biopsies

OBJECTIVE

To correlate high-risk HPV (hrHPV) detection by Hybrid Capture II (HC2) (Digene, Gaithersburg, Maryland, U.S.A.) with DNA content (ploidy) of cervical biopsies analyzed by a computer-assisted system.

STUDY DESIGN

Cervical biopsies from 54 women examined at Leonor Mendes de Barros Hospital, São Paulo, as part of the Latin American Screening study during 2002--2003, were tested for hrHPV with HC2. All patients had been referred for colposcopic examination due to an abnormal cervical cytology. The final diagnosis included 30 cervicitis, 14 cervical intraepithelial neoplasia (CIN) 1, 5 CIN 2, 4 CIN 3 and 1 squamous cell carcinoma (SCC). Five-micrometer sections of each biopsy were stained with Feulgen-tionine and evaluated with the CAS 200 System (Becton Dickinson, U.S.A.), using the 3.0 software (version 8.1) of the DNA Quantitative Measurement Program (Becton Dickinson). Ploidy was evaluated from histograms obtained by analyzing atypical nuclei.

RESULTS

Of the 30 cervicitis cases, 28 (93.3%) were diploid, and hrHPV was detected in 8 (28.5%) of the cases. Two tetraploid cervicitis lesions were observed, 1 positive and 1 negative for hrHPV. Among the CIN 1 lesions, 8 (57.1%) were diploid and 6 (42.8%) aneuploid. Of the latter, 4 (66.6%) were negative and 2 (33.3%) positive for hrHPV. Of the 5 CIN 2 lesions, 2 were diploid, 2 aneuploid and 1 tetraploid; all were positive for hrHPV. All CIN 3 lesions and the SCC proved to be aneuploid and positive for hrHPV.

CONCLUSION

The data suggest that the majority of cervicitis and CIN 1 lesions are diploid and negativef or hrHPV. This is in sharp contrast to high grade CIN 2-3 lesions, all of which were positive for hrHPV in this study and also aneuploid, consistent with their progressive potential.

Pap test in a high-risk population comparison of conventional and liquid-base cytology

Liquid-based cytology (LBC) is believed to have better sensitivity than conventional smears (CSs) and offers the possibility to perform molecular assay. The goal of this work was to study the performance of CS and LBC in a high-risk population and to compare the results with the hybrid capture (HC) II for high-risk human papillomavirus (HPV). Samples were collected from selected women with clinical suspicions of low genital tract lesion at Pérola Biygnton Hospital (São Paulo, Brazil). After CS preparation, the brush was introduced in the endocervix and a new sample was collected and rinsed in the preservative medium of the system. The residual material was used to HC2. From 925 cases, LBC was unsatisfactory in 4 (1.51%) cases and CS was unsatisfactory in 100 cases (10.81%); among theses cases HC2(+) reactions was observed in 54 (54%) CSs and 3 (21.4%) LBCs. Considering cases with atypia of undetermined significance (squamous and glandular), 85 (77.27%) cases from LBC and 44 (86.4%) from CS were positive for HC2 assay for high-risk DNA-HPV. The difference among the methods was not significant (P < 0.38). The diagnosis improvement of LBC in comparison with CS was 86% in satisfactory samples, 92.76% in undetermined atypical lesions (including glandular), 83% in positive low-grade squamous intraepithelial lesions (LSIL(+)), and 86.84% in high-grade SIL(+) (HSIL(+)). HC2(+) reactions were observed in 144 CS cases and 266 LBC cases with abnormalities. Our results have showed that LBC was superior to CS in a high-risk population to detect lesions with high concordance with HC2(+) reactions; CSs also exhibit a high concordance with HC2 assay but with inferior performance to detect lesions.

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.

Cervical intraepithelial neoplasia in adolescents: study of cytological findings between 1987 and 1995 in São Paulo State-Brazil

The purpose of the present study was to ascertain the frequency of Pap smears abnormalities (SIL/carcinoma) in two populations in the State of S. Paulo (Brazil) who were screened for cervical cancer during the last nine years: adolescents (up to the age of 21) and adults (over 21). Statistical analysis showed a tendency to linear increase in frequency of abnormal Pap smears in both groups (adolescent: slope = 0.118 +/- 0.56; adult: slope = 0.079 +/- 0.021), being greater in the adolescent group (slope 0.039 +/- 0.038) than in the adult group. Between 1987 and 1995 the prevalence of abnormal smears tripled in the adult group (from 0.37 to 1.18) and almost quadruplicated in the adolescent group (from 0.64 to 2.10). Low grade squamous intraepithelial lesions (SIL) were the most frequent findings in cervical cytology in both groups: 92.3% in the adolescent group and 69.8% in the adult group. Few cases of high grade squamous intrapeithelial lesions (HSIL) (7.7%) and no cases of carcinoma were found in adolescent population. We suggested that sexually active adolescents should be included in cervical screening programs.

[Quality assurance in cytopathology: aspects of the cytohistological correlation]

The cytohistologic diagnosis concordance of the cervix-uterine lesions was evaluated and the discordances are discussed.

PURPOSE

To evaluate the level of cytohistological diagnosis agreement in the Pathology Division of the Adolfo Lutz Institute and enhance parameters of quality assurance system developed in this institution.

METHODS

The authors retrospectively evaluated 157 pairs of cytologyhistology consecutive cases from the files the Adolfo Lutz Institute (Division of Pathology).

RESULTS

Agreement was found in 119 cases (75.8%); in the remaining cases cytologic diagnosis were higher than histology in 11 lesions (7.0%) and lower in 27 (17.2%). We also observed that in 5 cases previously diagnosed as inflammatory, 2 of them were reclassified as CIN 1; after revision, the others remained as inflammatory even though they had a histological diagnosis of CIN.

CONCLUSION

These results showed the role of cytohistological correlation to the quality assurance system of cytological diagnosis and also stressed the importance of taking the cervical scrapes with accurate care to avoid diagnostic discrepancies.

[Program of quality control in gynecologic cytology at the Adolfo Lutz Institute: strategies and critical analysis of results of its pilot implementation]

The Quality Control in the Gynecological Cytology Program, Instituto Adolfo Lutz, was designed to assure a high-standard of laboratory analysis for the Gynecological Cancer Detection and Prevention System in the São Paulo State Public Health Service. This study presents strategies for intra-laboratorial quality control as well as preliminary results on 32,018 cases. The methods applied for the selection of cases to be reviewed were based on clinical and cytological conditions that could mean higher risk of development of neoplasia and/or conditions that might induce difficulties of interpretation. The classification and analysis of the discrepancies found in this initial experience are the highlight points of this Program. Out of the 492 cases submitted to review, 45 had received underscored initial interpretation, although none of them fit international criteria for "false-negative". Overscores were found in 51 cases, with only three cases fitting the criteria for "false-positive". Based on this initial experience, the Quality Control Program will be applied to the other laboratories of the Public Health Service. This intra-laboratory model of control will be coupled with external supervision by Instituto Adolfo Lutz.