George Valasoulis

Human papillomavirus DNA and mRNA positivity of the anal canal in women with lower genital tract HPV lesions: Predictors and clinical implications

OBJECTIVE Women with HPV related pathology of the lower genital tract are at higher risk for AIN and anal cancer than the general population. A strategy to identify anal disease in these women has not been formulated. The aim of this study is to examine the feasibility of HPV related biomarker testing on anal smears, to identify the risk factors for anal HPV positivity and to provide information of the clinical implications of anal HPV infection in this population. METHODS In women referred for colposcopy because of HPV related pathology of the lower genital tract (cervical cancer, CIN, VIN, warts) a detailed questionnaire, an anal smear and a cervical smear were taken. On each sample morphological cytology, flow cytometric evaluation of E6&7 mRNA, and HPV DNA detection and typing were performed. Women with a positive anal result were referred for high resolution anoscopy. RESULTS So far 235 women have been included (mean age 34.3). HPV DNA, high-risk HPV DNA, high-risk mRNA was detected in 45%, 31% and 8% of the anal smears and in 56%, 39% and 25% of the cervical smears respectively. Absolute or partial concordance of the types between the cervix and the anus was seen in 74%. Positivity for mRNA was significantly lower in the anus than the cervix (8% vs 25%). Logistic regression analysis revealed risk factors for the presence of anal HPV DNA (>3 lifetime sexual partners and presence of cervical HPV DNA), hr HPV DNA (presence of cervical hr HPV DNA), and hr mRNA (presence of cervical hr mRNA). Twelve months after LLETZ 53% of women were cervical HPV negative, but 25% of those were still HPV positive in the anus. CONCLUSIONS HPV infection of the anus is common in this group and is interlinked with the cervical infection. Anal HPV E6&7 mRNA expression is less common than in the cervix. Possible clinical implications of anal infection could be the development of AIN and recurrence of CIN after treatment due to cervical reinfection from the anal reservoir. The use of HPV biomarkers is feasible in anal smears, although especially DNA testing as triage method for referral to anoscopy is probably inappropriate due to high positivity rate.

The evaluation of p16INK4a immunoexpression/immunostaining and human papillomavirus DNA test in cervical liquid-based cytological samples.

Aim: To evaluate the role of p16INK4a immunoexpression and human papillomavirus (HPV) DNA test for the detection of dyskaryotic cells in high-risk women. Materials and Methods: This work was a retrospective diagnostic study conducted in the University Hospital of Thessaloniki from January to December 2008. The subjects were women with current or previous HPV infection and current or previous cervical intraepithelial lesion (with or without treatment) or clinical warts. All liquid-based cytological samples were tested for P16INKa and HPV DNA test. The accuracy parameters used for the outcome included sensitivity, specificity, and positive predictive value. Results: A total of 226 women were included; the mean age was 29 years. Expression of p16INK4a was detected in the cytological samples of 13% of the negative cases, 44% of the cases of atypical squamous cells of undetermined significance, 46% of the cases of low-grade squamous intraepithelial lesion, and 78% of the cases of high-grade squamous intraepithelial lesion. A total of 91 women tested positive for high-risk HPV infection, and 54 of those had p16INK4a-positive staining reaction cells. The concordance between the 2 tests, HPV DNA and p16, was 59% regarding infection-positive cases. Diffuse strong parabasal p16INK4a immunostaining (nuclear score >2) was observed in 17 cases of the abnormal cytological findings (atypical squamous cells of undetermined significance, 2 cases; low-grade squamous intraepithelial lesion, 8 cases; high-grade squamous intraepithelial lesion, 7 cases). Colposcopy-directed biopsies were used as the criterion standard for the detection of cervical intraepithelial neoplasia in 91 women. The sensitivity of p16INK4a was 95% and the specificity was 92%, whereas the sensitivity of high-risk HPV was 100% and the specificity was 78%. The positive predictive value of p16INK4a was 71%, whereas that of HPV DNA was 44%. Conclusion: The findings suggest that p16INK4a immunostaining can improve the accuracy of cytological examination and HPV DNA test and may be particularly useful in the triage of low-grade lesions.

Proportion of cervical excision for cervical intraepithelial neoplasia as a predictor of pregnancy outcomes

To assess how the proportion of the cervical volume/length removed during treatment for cervical intraepithelial neoplasia (CIN) varies and whether this correlates to the pregnancy duration at delivery.

Histology Verification Demonstrates That Biospectroscopy Analysis of Cervical Cytology Identifies Underlying Disease More Accurately than Conventional Screening: Removing the Confounder of Discordance

Background Subjective visual assessment of cervical cytology is flawed, and this can manifest itself by inter- and intra-observer variability resulting ultimately in the degree of discordance in the grading categorisation of samples in screening vs. representative histology. Biospectroscopy methods have been suggested as sensor-based tools that can deliver objective assessments of cytology. However, studies to date have been apparently flawed by a corresponding lack of diagnostic efficiency when samples have previously been classed using cytology screening. This raises the question as to whether categorisation of cervical cytology based on imperfect conventional screening reduces the diagnostic accuracy of biospectroscopy approaches; are these latter methods more accurate and diagnose underlying disease? The purpose of this study was to compare the objective accuracy of infrared (IR) spectroscopy of cervical cytology samples using conventional cytology vs. histology-based categorisation. Methods Within a typical clinical setting, a total of n = 322 liquid-based cytology samples were collected immediately before biopsy. Of these, it was possible to acquire subsequent histology for n = 154. Cytology samples were categorised according to conventional screening methods and subsequently interrogated employing attenuated total reflection Fourier-transform IR (ATR-FTIR) spectroscopy. IR spectra were pre-processed and analysed using linear discriminant analysis. Dunn’s test was applied to identify the differences in spectra. Within the diagnostic categories, histology allowed us to determine the comparative efficiency of conventional screening vs. biospectroscopy to correctly identify either true atypia or underlying disease. Results Conventional cytology-based screening results in poor sensitivity and specificity. IR spectra derived from cervical cytology do not appear to discriminate in a diagnostic fashion when categories were based on conventional screening. Scores plots of IR spectra exhibit marked crossover of spectral points between different cytological categories. Although, significant differences between spectral bands in different categories are noted, crossover samples point to the potential for poor specificity and hampers the development of biospectroscopy as a diagnostic tool. However, when histology-based categories are used to conduct analyses, the scores plot of IR spectra exhibit markedly better segregation. Conclusions Histology demonstrates that ATR-FTIR spectroscopy of liquid-based cytology identifies the presence of underlying atypia or disease missed in conventional cytology screening. This study points to an urgent need for a future biospectroscopy study where categories are based on such histology. It will allow for the validation of this approach as a screening tool.

Identification of Women for Referral to Colposcopy by Neural Networks: A Preliminary Study Based on LBC and Molecular Biomarkers

Objective of this study is to investigate the potential of the learning vector quantizer neural network (LVQ-NN) classifier on various diagnostic variables used in the modern cytopathology laboratory and to build an algorithm that may facilitate the classification of individual cases. From all women included in the study, a liquid-based cytology sample was obtained; this was tested via HPV DNA test, E6/E7 HPV mRNA test, and p16 immunostaining. The data were classified by the LVQ-NN into two groups: CIN-2 or worse and CIN-1 or less. Half of the cases were used to train the LVQ-NN; the remaining cases (test set) were used for validation. Out of the 1258 cases, cytology identified correctly 72.90% of the CIN-2 or worst cases and 97.37% of the CIN-1 or less cases, with overall accuracy 94.36%. The application of the LVQ-NN on the test set allowed correct classification for 84.62% of the cases with CIN-2 or worse and 97.64% of the cases with CIN-1 or less, with overall accuracy of 96.03%. The use of the LVQ-NN with cytology and the proposed biomarkers improves significantly the correct classification of cervical precancerous lesions and/or cancer and may facilitate diagnosis and patient management.

Classification of cervical cytology for human papilloma virus (HPV) infection using biospectroscopy and variable selection techniques

Cervical cancer is the second most common cancer in women worldwide. We set out to determine whether attenuated total reflection Fourier-transform infrared (ATR-FTIR) spectroscopy combined with principal component analysis–linear discriminant analysis (PCA–LDA) or, variable selection techniques employing successive projection algorithm or genetic algorithm (GA) could classify cervical cytology according to human papilloma virus (HPV) infection [high-risk (hr) vs. low-risk (lr)]. Histopathological categories for squamous intraepithelial lesion (SIL) were segregated into grades (low-grade vs. high-grade) of cervical intraepithelial neoplasia (CIN) expressing different HPV infection (16/18, 31/35 or HPV Others). Risk assessment for HPV infection was investigated using age (≤29 years vs. >30 years) as the distinguishing factor. Liquid-based cytology (LBC) samples (n = 350) were collected and interrogated employing ATR-FTIR spectroscopy. Accuracy test results including sensitivity and specificity were determined. Sensitivity in hrHPV category was high (≈87%) using a GA–LDA model with 28 wavenumbers. Sensitivity and specificity results for >30 years for HPV, using 28 wavenumbers by GA–LDA, were 70% and 67%, respectively. For normal cervical cytology, accuracy results for ≤29 years and >30 years were high (up to 81%) using a GA–LDA model with 27 variables. For the low-grade cervical cytology dataset, 83% specificity for ≤29 years was achieved using a GA–LDA model with 33 wavenumbers. HPV16/18 vs. HPV31/35 vs. HPV Others were segregated with 85% sensitivity employing a GA–LDA model with 33 wavenumbers. We show that ATR-FTIR spectroscopy of cervical cytology combined with variable selection techniques is a powerful tool for HPV classification, which would have important implications for the triaging of patients.

The Application of Classification and Regression Trees for the Triage of Women for Referral to Colposcopy and the Estimation of Risk for Cervical Intraepithelial Neoplasia: A Study Based on 1625 Cases with Incomplete Data from Molecular Tests

Objective. Nowadays numerous ancillary techniques detecting HPV DNA and mRNA compete with cytology; however no perfect test exists; in this study we evaluated classification and regression trees (CARTs) for the production of triage rules and estimate the risk for cervical intraepithelial neoplasia (CIN) in cases with ASCUS+ in cytology. Study Design. We used 1625 cases. In contrast to other approaches we used missing data to increase the data volume, obtain more accurate results, and simulate real conditions in the everyday practice of gynecologic clinics and laboratories. The proposed CART was based on the cytological result, HPV DNA typing, HPV mRNA detection based on NASBA and flow cytometry, p16 immunocytochemical expression, and finally age and parous status. Results. Algorithms useful for the triage of women were produced; gynecologists could apply these in conjunction with available examination results and conclude to an estimation of the risk for a woman to harbor CIN expressed as a probability. Conclusions. The most important test was the cytological examination; however the CART handled cases with inadequate cytological outcome and increased the diagnostic accuracy by exploiting the results of ancillary techniques even if there were inadequate missing data. The CART performance was better than any other single test involved in this study.

Expression of HPV-related biomarkers and grade of cervical intraepithelial lesion at treatment.

New human papillomavirus (HPV)‐related biomarkers may allow better identification of clinically significant lesions that warrant excision and, conversely, identification of the false positive cases that have been overreported by traditional techniques. The aim of this study was to investigate how the expression of several HPV‐related biomarkers correlates to the severity of the lesion at treatment.