Improvement of Pap smear sensitivity using a visual adjunctive procedure: a co-operative Italian study on speculoscopy (GISPE)

Assessing colposcopic accuracy for high-grade squamous intraepithelial lesion detection: a retrospective, cohort study

Background

Inappropriate management of high-grade squamous intraepithelial lesions (HSIL) may be the result of an inaccurate colposcopic diagnosis. The aim of this study was to assess colposcopic performance in identifying HSIL+ cases and to analyze the associated clinical factors.

Methods

Records from 1130 patients admitted to Shenzhen Maternal and Child Healthcare Hospital from 12th January, 2018 up until 30th December, 2018 were retrospectively collected, and included demographics, cytological results, HPV status, transformation zone type, number of cervical biopsy sites, colposcopists’ competencies, colposcopic impressions, as well as histopathological results. Colposcopy was carried out using 2011 colposcopic terminology from the International Federation of Cervical Pathology and Colposcopy. Logistic regression modelling was implemented for uni- and multivariate analyses. A forward stepwise approach was adopted in order to identify variables associated with colposcopic accuracy. Histopathologic results were taken as the comparative gold standard.

Results

Data from 1130 patient records were collated and analyzed. Colposcopy was 69.7% accurate in identifying HSIL+ cases. Positive predictive value, negative predictive value, sensitivity and specificity of detecting HSIL or more (HSIL+) were 35.53%, 64.47%, 42.35% and 77.60%, respectively. Multivariate analysis highlighted the number of biopsies, cytology, and transformation zone type as independent factors. Age and HPV subtype did not appear to statistically correlate with high-grade lesion/carcinoma.

Conclusion

Evidence presented here suggests that colposcopy is only 69.7% accurate at diagnosing HSIL. Even though not all HSIL will progress into cancer it is considered pre-cancerous and therefore early identification will save lives. The number of biopsies, cytology and transformation zone type appear to be predictors of misdiagnosis and therefore should be considered during clinical consultations and by way of further research.

Noninvasive Point-of-Care Nanobiosensing of Cervical Cancer as an Auxiliary to Pap-Smear Test

A potential cancer antigen (Ag), protein-phosphatase-1-gamma-2 (PP1γ2), with a restricted expression in testis and sperms has been identified as a biomarker specific to cervical cancer (CaCx). Detection of this cancer biomarker antigen (NCB-Ag) in human urine opens up the possibility of noninvasive detection of CaCx to supplement the dreaded and invasive Pap-smear test. A colorimetric response of an assembly of gold nanoparticles (Au NPs) has been employed for the quantitative, noninvasive, and point-of-care-testing of CaCx in the urine. In order to fabricate the immunosensor, Au NPs of sizes ∼5-20 nm have been chemically modified with a linker, 3,3'-di-thio-di-propionic-acid-di(n-hydroxy-succinimide-ester) (DTSP) to attach the antibody (Ab) specific to the NCB-Ag. Interestingly, the addition of Ag to the composite of Ab-DTSP-Au NPs leads to a significant hypsochromic shift due to a localized surface plasmon resonance phenomenon, which originates from the specific epitope-paratope interaction between the NCB-Ag and Ab-DTSP-Au NPs. The variations in the absorbance and wavelength shift during such attachments of different concentrations of NCB-Ag on the Ab-DTSP-Au NPs composite have been employed as a calibration to identify NCB-Ag in human urine. An in-house prototype has been assembled by integrating a light-emitting diode of a narrow range wavelength in one side of a cuvette in which the reaction has been performed while a sensitive photodetector to the other side to transduce the transmitted signal associated with the loading of NCB-Ag in the Ab-DTSP-Au NPs composite. The proposed immunosensing platform has been tested against other standard proteins to ensure noninterference alongside proving the proof-for-specificity of the NCB detection.

Acetic-acid guided visual inspection vs. cytology-based screening for cervical cancer in the Philippines

OBJECTIVES

To compare the validity and acceptability of acetic-acid visualization (VIA), magnified acetic-acid visualization (VIAM), spatula+cotton swab-Papanicolaou (Pap) smear (SS), and cervical brush-Pap smear (CB) in the detection of precursor/early cervical cancer lesions.

METHODS

A total of 12992 women aged between 25 and 65 years from 14 Philippine centers were randomly allocated to the four tests. The gold standard was colposcopy with biopsy for positive/suspicious cases.

RESULTS

Sensitivity rates [95% confidence intervals (CIs)] were 37 (CI, 26.8-48.5), 34.1 (CI, 24.8-44.8), 14.3 (CI, 6.4-27.8), and 19.1 (CI, 9.2-34.6) for VIA, VIAM, SS, and CB, respectively. Specificity rates were 90.7 (CI, 89.6-91.7), 90.7 (CI, 89-91.1), 97.5 (CI, 96.8-98), and 97.9 (CI, 97.3-98.4), respectively. Kappa for the Pap smear (PS) within centers ranged from -0.154 to 0.783, and between centers from -0.028 to 0.364. Screeners preferred CB; screened-women preferred VIA.

CONCLUSIONS

The acetic-acid visualization and VIAM methods are recommended for initial cervical cancer screening in the Philippines.

Accuracy of Colposcopically Guided Diagnostic Methods for the Detection of Cervical Intraepithelial Neoplasia

Introduction: Many factors can affect the accuracy of colposcopically guided biopsy, endocervical curettage (ECC) and differential cytology, all of which are standard, minimally invasive procedures used to detect cervical intraepithelial neoplasia. Method: All conizations carried out between 2007 and 2013 in the gynecological department of Hannover Medical School were retrospectively reviewed. The agreement between colposcopic diagnosis and histology was evaluated retrospectively. The analysis included 593 complete datasets out of a total of 717 cases treated. Results: The overall agreement was 85.5 %; the accuracy was significantly higher (p = 0.029) when three biopsy specimens were taken rather than just one. The agreement between diagnosis and histological findings from conization was highest for women < 30 years (90.7 %) and lowest for women > 50 years (72.1 %; p = 0.008). The agreement between preoperative differential cytology and histology results after conization was 86.7 % and improved as patient age increased (p = 0.035). The agreement between ECC findings and the results of conization was only 49.1 % irrespective of patient age, transformation zone or the patient's menopausal status. Conclusion: The accuracy of colposcopically guided biopsy appears to increase when three biopsy specimens are taken and is particularly high for younger patients. Differential cytology was also found to be highly accurate and is particularly useful for patients aged more than 50 years. The accuracy of ECC was significantly lower; however ECC can provide important additional information in selected cases.

PAX1 methylation as a potential biomarker for cervical cancer screening

OBJECTIVES

DNA methylation is a potential biomarker for early cancer detection. Previous studies suggested that the methylations of several genes are promising markers for the detection of cervical intraepithelial neoplasia at grade III or worse (CIN3+). The purpose of the present study was to explore the feasibility of these DNA methylation testing in cervical cancer screening.

METHODS

A total of 443 women were recruited from the Yuan's General Hospital. Cervical scrapings were collected for Papanicolaou (Pap) test by using cervical brushes, and the cytological data were used for analysis. The residual cells on the brush were preserved in phosphate-buffered saline solution at 4°C until DNA extraction. Then, the extracted DNA were used for molecular tests, which included human papillomavirus typing and quantification of the methylation levels for PAX1, SOX1, and NKX6-1 genes. Subjects who had abnormal Pap test results underwent colposcopy or biopsy with subsequent conization or major surgery when biopsy results revealed CIN2+. The final diagnosis for this group was confirmed by colposcopy or pathological examination. The study was approved by the institutional review board of Yuan's General Hospital, and all the molecular tests were performed by ISO17025 certified laboratories.

RESULTS

The sensitivity of PAX1 and SOX1 was greater than 80%, and the specificity of PAX1 and NXK6-1 was greater than 80% for the detection of CIN3+ lesions. PAX1 detection alone had a sensitivity and specificity of 86% and 85%, respectively, whereas when used as a cotest with the Pap test, the sensitivity and specificity were 89% and 83%, respectively.

CONCLUSIONS

PAX1 showed great potential as a biomarker for cervical cancer screening. When incorporating PAX1 detection into current screening protocol, the efficacy of screening could be greatly improved. Moreover, unnecessary referral for colposcopy and biopsy could be reduced up to 60%. However, prospective population-based studies are necessary for further implementation of this screening program.

LUMA™ Cervical Imaging System

For approximately 30 years colposcopically directed biopsy of the uterine cervix has been the gold standard for the detection of cervical intraepithelial neoplasia (CIN) and cancer following an abnormal Papanikolaou (Pap) smear. Recent technological advancements utilizing properties of fluorescence, reflectance and spectroscopy intrinsic to in vivo tissues, have led to the development of a useful adjunct to improve colposcopic detection of high-grade CIN. The addition of the LUMA (MediSpectra, Inc., MA, USA) cervical imaging system to colposcopy has been shown in two prospective, randomized controlled trials to result in a 25% or greater increase in the true positive biopsy rate of colposcopy for patients with atypical squamous cell or low-grade squamous intraepithelial lesions on Pap smear, with only a 4% increase in the false-positive rate, versus that of colposcopy alone. The US FDA approved this device in March 2006 to be used to enhance the sensitivity of colposcopic examinations of women with abnormal cervical cytology, in an effort to further reduce the incidence of cervical cancer.

Analysis of oral lesion biopsies identified and evaluated by visual examination, chemiluminescence and toluidine blue

Conventional visual examination and palpation remains the gold-standard for the identification of oral mucosal lesions. The purpose of this study was to investigate the adjunctive value of a chemiluminescent light source (ViziLite, Zila Pharmaceuticals, Phoenix, Arizona) and application of pharmaceutical grade toluidine blue (TBlue(630), Zila Pharmaceuticals, Phoenix, Arizona) to further assess lesions identified during the conventional oral soft tissue examination. Lesions deemed clinically suspicious by visual examination under incandescent light were further assessed under chemiluminescence and then application of toluidine blue stain. Differences between the conventional visual examination and chemiluminescent examination were noted on four characteristics which may aid in lesion identification. Tissue retention of toluidine blue stain was documented. Each suspicious lesion was biopsied and diagnosed based upon routine histopathology. Both adjunctive exams were evaluated by comparing the histologic diagnosis. The additive value of toluidine blue stain retention was assessed in lesions diagnosed as "serious pathology" defined as severe dysplasia, carcinoma in situ and squamous cell carcinoma. Ninety-seven clinically suspicious lesions in 84 patients were identified. The chemiluminescent exam improved the brightness and/or sharpness of margin in 61.8% of identified lesions. Biopsied lesions with toluidine blue stain retention reduced the false positive rate by 55.26% while maintaining a 100% negative predictive value (NPV). Chemiluminescence was shown to increase the brightness and margins of mucosal lesions in a majority of cases and therefore may assist in identification of mucosal lesions not considered under traditional visual examination. Toluidine blue stain retention was associated with a large reduction in biopsies showing benign histology (false positive biopsy results), while maintaining a 100% NPV for the presence of severe dysplasia or cancer. Practitioners may consider use of these adjuncts in practice, however the results presented are based upon experienced providers in referral centers for mucosal disease or cancer centers and therefore positive findings may be an indication for referral to experienced providers.

The efficacy of oral lumenoscopy (ViziLite) in visualizing oral mucosal lesions

Early diagnosis of oral mucosal lesions has been advocated as a means of improving outcomes of cancer therapy. Improved visualization of mucosal lesions may aid in diagnosis by guiding tissue sampling or referral. This multicenter study reports the effect of chemiluminescent light (ViziLite) upon visualization of mucosal lesions. The chemiluminescent light did not appear to improve visualization of red lesions, but white lesions and lesions that were both red and white showed enhanced brightness and sharpness.

Improved cervical cancer screening in premenopausal women by combination of Pap smear and speculoscopy

OBJECTIVE

This study was done to evaluate the efficacy of the Pap smear, speculoscopy, and a combination of Pap smear and speculoscopy (PapSure examination) in pre- and postmenopausal women.

STUDY DESIGN

All women were screened using the Pap smear and speculoscopy and combination of both (PapSure examination) in the multicenter trial. Final diagnosis of each patient was based on a histological evaluation of the colposcopic target biopsy. Results were analyzed using a proportional comparison test, sensitivity, specificity, and predictive value with significance determined at p<0.05.

RESULTS

Of 1813 women screened, 1701 were eligible for analysis. Two hundred and fourteen women (12.6%) received at least one positive screening test result. Of the 1084 colposcopic biopsy specimens obtained, 24 showed low-grade squamous intraepithelial lesion (LSIL) and 19 high-grade SIL (HSIL). HSIL were considered test-positive. Rate of colposcopy was 21.5% (125/582) in the premenopausal group and 63.9% (321/502) in the postmenopausal group (p<0.001). For premenopausal women, speculoscopy (75.0%) or PapSure (91.7%) provided higher sensitivity than Pap smear (50%) (p<0.05). In postmenopausal women, no statistical significance in sensitivity existed between PapSure (85.7%) and Pap smear (57.1%). Speculoscopy (96.8%) or PapSure (96.5%) had lower specificity than Pap smear (99.6%) (p<0.001).

CONCLUSION

PapSure was an accurate alternative screening method to Pap smear or speculoscopy for cervical intraepithelial lesions because of a significantly higher sensitivity along with adequate specificity for premenopausal women; however, PapSure was not a more effective cervical screening method for postmenopausal women.

Cervical Cancer Screening

Cervical cytology has proved to be one of the most successful examples of cancer screening and has resulted in significant decreases in incidence and mortality from invasive cervical cancer in regions in which comprehensive programs have been instituted. A standardized system of reporting abnormal cervical cytology, the Bethesda System has been developed and revised to reflect our current understanding of HPV-related precancers. The Pap smear has been the backbone of cervical cancer screening programs in North America over the past five decades; however, recent advances, including liquid-based cytology, HPV typing, and direct visualization techniques, are proposed to address the inherent weaknesses of cytologic screening in women who are screened. The problem of unscreened and underscreened women exists and accounts for most cases of invasive cancer. Widespread screening hopefully one day will lead to a significant decrease in the mortality of cervical cancer, the second most common female malignancy worldwide. Another means of preventing this disease involves HPV vaccines, which are in development but are not ready for use outside of a clinical trial.

Knowledge of oral cancer risk factors and diagnostic concepts among North Carolina dentists

BACKGROUND

Dentists play a critical role in the early detection of oral and pharyngeal cancer (OPC). The authors administered a survey that assessed the level of knowledge among dentists regarding risk factors and diagnostic concepts.

METHODS

In 2002, the authors mailed a 38-item, pretested survey to a random sample of 1,115 licensed dentists practicing in North Carolina. Three-level (low, medium, high) composite index scores for knowledge of risk factors and diagnostic concepts were created using previously developed scales. The authors formulated multivariable models for risk factor and diagnostic knowledge indexes.

RESULTS

Of the 584 respondents, only 181 (31 percent) had consistent medium-to-high levels of knowledge on both highly correlated indexes. Dentists who had higher risk factor and diagnostic knowledge scores were significantly (P < .05) more likely to have heard of one or more diagnostic aids (odds ratio [OR], 2.7), to have graduated from dental school within the previous 20 years (OR, 1.8) and to have performed biopsies or referred five or more patients with suspicious lesions per year (OR, 1.7 and 1.5, respectively) than were less-knowledgeable respondents.

CONCLUSIONS

More education is needed in dental schools, postgraduate programs and continuing education programs to enhance dental professionals' knowledge of OPC risk factors and diagnostic concepts. Such programs should include information about adjunctive diagnostic aids.

PRACTICE IMPLICATIONS

Greater knowledge of risk factors and diagnostic concepts may result in more frequent patient referrals, biopsy procedures or both, thus aiding in the early diagnosis and treatment of patients with OPC.

False-Negative Hybrid Capture II Results Related to Altered Adhesion Molecule Distribution in Women with Atypical Squamous Cells Pap Smear Results and Tissue-Based Human Papillomavirus-Positive High-Grade Cervical Intraepithelial Neoplasia

OBJECTIVE

We investigated the detection of high-risk human papillomavirus DNA with the Hybrid Capture II test (HCII; Digene Corporation, Beltsville, MD) and the presence and pattern of distribution of adhesion molecules in biopsy-proven high-grade neoplastic lesions containing high-risk HPV-DNA from women with ASC cytology results.

MATERIALS AND METHODS

We screened 4,600 women and performed colposcopy in 278 women with atypical squamous cells cytologic results. All women underwent HCII and tissue-based polymerase chain reaction analysis for high-risk HPV subtypes. Of 33 women with cervical intraepithelial neoplasia (CIN) 2 or worse biopsy results, 27 biopsy specimens contained sufficient tissue to perform immunohistochemical testing (pathologist blinded as to cytologic and HCII results) for adhesion molecules beta-catenin and 21 cases for E-cadherin.

RESULTS

Five of 27 specimens with CIN 2 or worse biopsy results (18.5%) had negative HCII results. All five specimens showed evidence of high-risk human papillomavirus by polymerase chain reaction analysis. All five showed full-thickness distribution via immunohistochemical staining for beta-catenin. There was sufficient tissue to examine four of five specimens for E-cadherin, and a full-thickness distribution also was documented.

CONCLUSIONS

Previous research linked false-negative cytologic results in women with high-grade CIN to altered adhesion molecule distribution and impaired exfoliation, and a similar phenomenon may be responsible for false-negative HCII results in women with atypical squamous cells cytologic results and high-grade CIN.

Comparison of cell collection and direct visualization cervical cancer screening adjuncts

Worldwide, invasive cancer of the cervix is the second most common malignancy in women. Each year, approximately 400,000 women are diagnosed with invasive cancer of the cervix, whereas 200,000 women die from the disease. In the United States, in 2002, there were 12,900 newly diagnosed cases of invasive cervical cancer and 4,400 cervical cancer-related deaths. Data from a recent meta-analysis found that the mean sensitivity of the conventional Papanicolaou (Pap) smear in screening populations was only 47%. These data, and others, underscore the need for more reliable and sensitive methods to screen for cervical cancer precursors. One example is the PapSure screening examination, at this point the only in-office direct visual cervical screening examination cleared by the US Food and Drug Administration. This cervical screening examination combines the traditional Pap smear with a direct visual screening test, speculoscopy (ie, visual inspection of the cervix with a chemiluminescent light, the Speculite).

Use of visual screening methods for cervical cancer screening

This article has considered recent advances in visual screening methods. Devices that use electro-optical sensors offer great potential in various clinical roles, but considerable additional work is required to develop these devices and it is unlikely that they will come into widespread clinical use in the next 5 years. In contrast numerous studies, demonstrate that simple visual screening methods, such as DVI, have a sensitivity for the detection of women with biopsy-confirmed high-grade SIL (CIN 2,3) and cancer that is equivalent to that of conventional cervical cytology. The primary disadvantage of the simple visual screening methods is poor specificity. These methods classify up to 30% of all women screened as being test positive and as a result new strategies toward managing DVI positive women must be developed before simple visual screening methods can be adopted for routine screening. Enhanced visual methods that use cervicography and speculoscopy may be more specific and improve detection of biopsy-confirmed SIL, but the added time and expense to perform either of these methodologies must be considered and justified. Currently numerous studies are evaluating the best strategies for incorporating visual screening methods into cervical cancer screening programs. In the near future we should be able to determine whether these approaches should be incorporated into routine clinical care.

Aberrant expression of E-cadherin in cervical intraepithelial neoplasia correlates with a false-negative Papanicolaou smear

OBJECTIVES

E-cadherin is responsible for cell adhesion in normal cervical epithelium. It is normally absent in the superficial epithelial layers, allowing for exfoliation. We investigated the correlation between E-cadherin distribution and Papanicolaou smear in subjects with cervical dysplasia.

STUDY DESIGN

Tissue samples from 25 women with cervical dysplasia were tested for E-cadherin, beta-catenin, and alpha-catenin expression by immunohistochemistry. The expression pattern of these proteins, whether full thickness or restricted to the basal layers, was correlated with the Papanicolaou smear result.

RESULTS

Of 12 women with normal Papanicolaou smears, 10 of 11 informative cases demonstrated E-cadherin expression throughout all epithelial layers. Eight of 10 informative cases with an abnormal Papanicolaou smear showed E-cadherin only at the basal layers. Alpha-catenin was distributed throughout the entire epithelium in samples of all 25 women.

CONCLUSIONS

Expression of E-cadherin throughout all epithelial layers was correlated with a false-negative Papanicolaou smear. It is likely that aberrant persistence of E-cadherin in these lesions interferes with the exfoliation of abnormal cells.

Speculoscopy for Triage of Patients with an Abnormal Pap Smear: Data from the GISPE Study

OBJECTIVE

This study evaluates the performance of Papanicolaou smear combined with speculoscopy in improving the predictive value of minor grade cervical cytological abnormalities.

MATERIALS AND METHODS

A total of 3,300 asymptomatic women who had routine cervical smears were studied in 32 Italian centers. All these women underwent Pap smear and speculoscopy. The women positive at Pap smear or speculoscopy (n = 908) were referred for colposcopy and directed punch biopsy/endocervical curettage was performed when appropriate.

RESULTS

Of the 908 patients referred for colposcopy, 538 underwent biopsy; 92 of these had a cervical lesion (cervical intraepithelial neoplasia [CIN]) confirmed on histology (67 CIN1 and 25 CIN2-3). Speculoscopy pointed out an area to biopsy in 84% of the CIN1 and in 75% of the CIN2-3 cases among women who showed minor (low-grade squamous intraepithelial lesion or less) cytological abnormalities.

CONCLUSIONS

The potential combination of cytology and speculoscopy as an intermediate test in patients with minor grade cytologic (atypical squamous cells of undetermined significance or low-grade squamous intraepithelial lesion) cervical changes may decrease the number of recalls and directed biopsies in a cost-effective manner.

Accuracy of the Papanicolaou test in screening for and follow-up of cervical cytologic abnormalities: a systematic review

PURPOSE

To evaluate the accuracy of conventional and new methods of Papanicolaou (Pap) testing when used to detect cervical cancer and its precursors.

DATA SOURCES

Systematic search of English-language literature through October 1999 using MEDLINE, EMBASE, other computerized databases, and hand searching.

STUDY SELECTION

All studies that compared Pap testing (conventional methods, computer screening or rescreening, or monolayer cytology) with a concurrent reference standard (histologic examination, colposcopy, or cytology).

DATA EXTRACTION

Two reviewers independently reviewed selection criteria and completed 2 x 2 tables for each study.

DATA SYNTHESIS

94 studies of the conventional Pap test and three studies of monolayer cytology met inclusion criteria. No studies of computerized screening were included. Data were organized by cytologic and histologic thresholds used to define disease. For conventional Pap tests, estimates of sensitivity and specificity varied greatly in individual studies. Methodologic quality and frequency of histologic abnormalities also varied greatly between studies. In the 12 studies with the least biased estimates, sensitivity ranged from 30% to 87% and specificity ranged from 86% to 100%.

CONCLUSIONS

Insufficient high-quality data exist to estimate test operating characteristics of new cytologic methods for cervical screening. Future studies of these technologies should apply adequate reference standards. Most studies of the conventional Pap test are severely biased: The best estimates suggest that it is only moderately accurate and does not achieve concurrently high sensitivity and specificity. Cost-effectiveness models of cervical cancer screening should use more conservative estimates of Pap test sensitivity.

Advances in cervical screening technology

The Pap smear unquestionably is a successful screening test for cervical cancer. However, recent advances in technology have raised questions regarding whether the conventional Pap smear is still the standard of care. This article relates issues of screening and cost-effectiveness to the state of the art in thin layer preparations, cytology automation, human papillomavirus screening, human papillomavirus vaccines, and other cervical screening adjuncts. Perhaps nowhere in medicine is clinical decision making being more strongly influenced by market and other external forces than in cervical cytopathology.