Liquid-based cytology and conventional cervical smears

Factores que afectan la suficiencia e interpretación de la citología de cuello uterino

Objetivo: evaluar los factores que afectan la suficiencia e interpretación de la citología de cuello uterino. Materiales y métodos: estudio transversal y retrospectivo en el Hospital Central “Dr. Urquinaona”, Maracaibo, Venezuela con la revisión de las historias clínicas e informes de las citologías de cuello uterino de la consulta de ginecología y obstetricia de enero a diciembre 2019. Se analizan las características generales y la clasificación de los informes (satisfactorios para la evaluación, satisfactorios pero limitados por y no satisfactorios). Resultados: se seleccionaron 581 informes de los cuales 329 (56,6%) eran muestras satisfactorias, 233 (40,1%) satisfactorias pero limitadas y 19 (3,3%) insatisfactorios. El análisis univariante demostró que la muestra insatisfactoria, la presencia síntomas al momento de la toma y el tipo de método anticonceptivo fueron factores que se asociaron significativamente (p < 0,0001). Los que influyeron para un resultado anormal de la citología cervical fueron frotis satisfactorio (razón de probabilidad, 4,78; intervalo de confianza del 95%, 3,127-8,136) y presencia de síntomas (razón de probabilidad, 11,652; intervalo de confianza del 95%, 2,992-38,55). Esta asociación continuó siendo significativa luego de ajustarlos a los factores de edad, paridad, edad al momento de la toma de la primera citología y método de anticoncepción (p < 0,0001). Conclusión: la suficiencia de la muestra de citología es un factor importante para la detección de anomalías celulares de cuello uterino y evitar resultados falsos negativos, retrasando la detección del cáncer.

Impact of LBC fixative type and fixation time on molecular analysis of pancreatic cancer cells: A comparative study of cell morphology, antigenicity and nucleic acids

Introduction:

Liquid-based cytology (LBC) has been widely used since 2000. Next-Generation Sequencing (NGS) analysis of residual specimens in LBC fixative may also be performed for pancreatic cancer in the near future. We examined cell morphology, antigenicity and nucleic acids in pancreatic cancer cells at different fixation times using two types of LBC fixatives.

Methods:

PANC-1 cells were fixed in 1 ml CytoRich Red (CR), CytoRich Blue (CB), 95% ethanol (95% AL) or 10% neutral buffered formalin (10% NBF) and evaluated for cell area, antigenicity and nucleic acids with fixation times of 1 hour and 1, 3, 9, and 14 days. Antigenicity was evaluated by immunocytochemical staining for p53 and CK20, and nucleic acid fragmentation was assessed by real-time PCR.

Results:

There was no difference in total cell area between 1 hour and 14 day fixation times for the CR group, but the CB group showed cell contraction with 9 days fixation. In immunocytochemical staining, the CR group showed high p53 and CK20 positivity even after 14 days fixation. The CB group had a lower p53 positive rate than the CR group from 1 hour fixation. For nucleic acid fragmentation, Ct values for the CR group increased with fixation time. The CB group had consistently low Ct values.

Conclusion:

Different LBC fixatives and fixation time can have varying effects on cell morphology, antigenicity and nucleic acids in pancreatic cancer cells. Therefore, fixative type and fixation time should be considered for molecular testing on residual samples in LBC fixatives.

Coexisting cancers with atypical glandular abnormalities by liquid-based cytology: A retrospective study in tertiary hospital in a high cervical cancer incident country

OBJECTIVE

To determine the incidence of coexisting cancers in women with glandular cell abnormalities detected from liquid-based cytology and to compare the detection rate of premalignant and malignant lesions among various subtypes of glandular cell abnormalities.

MATERIALS AND METHODS

From January 2014 to December 2016, liquid-based cytology was performed in 85,517 women. Using the Bethesda system 2001 criteria, abnormal cervical cytology was diagnosed in 3650 women (4.3%). Glandular cell abnormalities were diagnosed in 110 women (0.13%). Ten women with pre-existing genital tract cancers and 13 women who lost to follow up were excluded. Clinical characteristic, colposcopic finding, and histopathological data were reviewed in 87 women.

RESULTS

High-grade premalignant and malignant lesions were diagnosed in 34 patients (39.1%). Co-existing cancer was diagnosed in 31 patients (35.6%); 15 cervical cancers (17.2%) and 16 endometrial cancers (18.4%). The detection rate of significant lesions (CIN2+ or malignant lesions) in patients with AGC-NOS was 14.9%, AGC-FN was 38.9% and AIS/adenocarcinoma was 90.9% (p < 0.001).

CONCLUSION

Glandular cell abnormalities associated with high incidence of coexisting endometrial and cervical cancers. Comprehensive genital tract screening to evaluate gynecologic malignancy is strongly recommended in all women with glandular cell abnormalities.

Method for preservation of DNA stability of liquid-based cytology specimens from a lung adenocarcinoma cell line

Liquid-based cytology (LBC) specimens of lung adenocarcinoma have the potential to be widely used for genetic analysis. However, formaldehyde contained in some LBC preservation solutions can cause DNA fragmentation during specimen storage, rendering the samples unsuitable for molecular analysis. To investigate a novel preservation technique for improved DNA stability, which was evaluated by mutation analysis of epidermal growth factor receptor (EGFR) gene in human lung adenocarcinoma cell lines. Cells were fixed in CytoRich Red preservation solution. After 30 min of fixation, cells were either stored using the conventional method (suspended in preservation solution) or washed in phosphate-buffered saline and stored as a cell pellet (newly proposed method). The effect of storage was evaluated after 5, 7, and 9 days of storage at ambient temperature. The cell pellet group was also tested after 14 and 28 days. Specifically, we evaluated the DNA stability, DNA yield, and sample suitability for polymerase chain reaction (PCR), and EGFR mutation detection. The DNA yields and degree of stability from the cell pellet group were higher than those from the suspension group at every time point examined. PCR amplification from the cell pellet group was successful up to day 28. Mutation detection using the Cycleave PCR method indicated that the Ct values of the cell pellet group were significantly lower than those of the suspension group. Storing LBC specimens as a cell pellet post-fixation can maintain the DNA quality for a longer period than the conventional method, making it a promising strategy for molecular analysis.

Diagnostic Accuracy of Cervical Pap Smear and Colposcopy in Detecting Premalignant and Malignant Lesions of Cervix

The objective of this study was to determine the diagnostic accuracy of pap smear and colposcopy in detecting the premalignant and malignant lesion of the cervix. In this cross-sectional study, a total number of 160 women who presented with abnormal clinical problem or routine checkup during a 6-month period were included. All the patients underwent pap smear and colposcopy by the same gynecologists team, and finally, cervical biopsy was performed in all the individuals. The demographic and clinical characteristics as well as the obstetrics history were recorded. The diagnostic accuracy of each test was calculated according to the biopsy as gold standard. The sensitivity, specificity, positive predictive value (PPV), and negative predictive values (NPV) were recorded and compared between two modalities. Overall, we included a total number of 160 patients with mean age of 37.6 ± 7.32 (ranging from 24 to 63) years. The sensitivity and specificity of pap smear were found to be 47.19% and 64.79%, respectively. The PPV and NPV of the pap smear were calculated to be 88.69% and 38.46%, respectively. The sensitivity and specificity, PPV, and NPV of the colposcopy were calculated as 64.72%, 52.74%, 76.32%, and 95.41%, respectively. The overall diagnostic accuracy of the pap smear and colposcopy was reported to be 82.2% and 96.3%, respectively. The results of this study demonstrate that colposcopy has a higher diagnostic accuracy in detecting cervical premalignant and malignant lesions compared to the pap smear.

Primary HPV testing with cytology versus cytology alone in cervical screening-A prospective randomized controlled trial with two rounds of screening in a Chinese population

We conducted a prospective randomized controlled trial with two screening rounds to evaluate the effectiveness of combining HPV testing with liquid-based cytology (LBC) as a co-test, compared to LBC only in cervical cancer screening of a Chinese population. First, 15,955 women aged 30-60 were randomized at a 1:1 ratio into an intervention group (Digene Hybrid Capture 2 HPV test with LBC) and a control group (LBC alone). Women in the intervention group would be referred for colposcopy and biopsy immediately if they were found to have high-risk HPV regardless of cytology results. The detection of cervical intraepithelial neoplasia grade 2 or above (CIN2+) lesions was significantly higher in the intervention group compared to the control (0.95% vs. 0.38%, OR 2.50, 95% CI 1.65-3.88). At the subsequent round of screening approximately 36 months later, CIN2+ detection was significantly lower in the intervention group (0.08% vs. 0.35%, OR 0.23, 95% CI 0.08-0.57). Over the two rounds of screening, the total detection of CIN2+ was higher in the intervention group (1.01% vs. 0.66%, OR 1.53, 95% CI 1.09-2.19). There was a fourfold increase (10.6% vs. 2.4%, p < 0.001) in the number of colposcopies performed in the intervention arm. Adding a high-risk HPV test to cytology for primary cervical screening led to earlier detection of clinically significant preinvasive lesions, resulting in a reduced detection of CIN2+ lesions in subsequent rounds and an increased rate of colposcopy.

Diagnostic efficacy of smear plus liquid-based cytology for EUS-FNA of solid pancreatic lesions: A propensity-matched study

Liquid-based cytology (LBC) is a thin-layer slide preparation procedure that was developed to overcome the cell crowding and contamination associated with smear cytology (SC). The present study compared diagnostic efficacy between SC alone and SC combined with LBC (SLBC) using endoscopic ultrasound-guided fine needle aspiration (EUS-FNA) samples of pancreatic lesions.We retrospectively analyzed data derived from 311 consecutive patients. Specimens obtained via EUS-FNA from 179 patients between December 2011 and May 2016 were analyzed by SC, and those obtained from 132 patients between June 2016 and October 2017 were analyzed by SLBC. The 2 groups were compared in terms of adequate sample rate, diagnostic accuracy, sensitivity, and specificity using propensity score matching.SC and SLBC were compared using propensity score-matching in 204 patients (n = 102 per group). The adequate sample rate did not differ significantly between SLBC (100%) and SC (99.0%, P = 1). Diagnostic sensitivity, negative predictive value and accuracy were better for SLBC than for SC in terms of cytological (93.2% vs 67.4%, 68.4% vs 23.1%, and 94.1% vs 69.6%, P < .01 each, respectively) and cytohistological (95.5% vs 81.5%, 76.5% vs 34.6%, and 96.1% vs 82.4%, P < .01, P = .02, and P < .01, respectively) analyses.SLBC improves the diagnostic efficacy of EUS-FNA for pancreatic lesions compared to LBC.

Comparison of conventional Pap smear and liquid-based cytology: A study of cervical cancer screening at a tertiary care center in Bihar

Background

Cervical cancer is the fourth leading cause of cancer in women in the world and it is the second most common cancer in women 15-44 years of age. Strict implementation of screening programs has led to a large decrease in cervical cancer incidence and mortality in the developed countries. In contrast, cervical cancer remains largely uncontrolled in high-risk developing countries because of ineffective or no screening programs. Conventional Pap smear method has been the mainstay of most of the screening programs for many decades. However, this technique is not without limitations, and the sensitivity and specificity of cervical cytology are relatively low. To overcome the limitations of conventional Pap smear (CPS), liquid-based cytology (LBC) was introduced in 1990s as a better tool for processing cervical samples.

Objectives

This study was undertaken to compare CPS with liquid-based methods, to assess the effectiveness and feasibility of LBC over CPS in our setting, and also to evaluate the prevalence of human papillomavirus (HPV) in our population.

Materials and Methods

This study was conducted in Gynecological Oncology Unit of Regional Cancer Center at Indira Gandhi Institute of Medical Sciences, Patna, Bihar. About 310 women were enrolled in this study and the sample was taken for both conventional cytology and LBC. The smears were studied in detail and were interpreted as per the Bethesda system of reporting Pap smears. The results were compared and analyzed statistically.

Results

Unsatisfactory smears were more commonly reported by conventional method (7.1%) than with liquid-based method (1.61%), and this difference is statistically significant. There was no difference in the detection of epithelial cell abnormalities using both the methods. HPV DNA for high-risk oncogenic strains (16 and 18) was detected in 6.45% of women in this study.

Conclusion

LBC has been found to be more superior to conventional smears only with respect to lesser number of unsatisfactory smears, but considering the economic implications of LBC, conventional Pap is more feasible in our setting.

Reducing DNA damage by formaldehyde in liquid-based cytology preservation solutions to enable the molecular testing of lung cancer specimens

BACKGROUND

Liquid-based cytology (LBC) is a useful cytopathological method, and LBC lung adenocarcinoma specimens may be used for genetic analysis in the near future. In the current study, the authors determined whether LBC specimens can be used for epidermal growth factor receptor (EGFR) mutation analysis in human lung adenocarcinoma cell lines.

METHODS

Genomic DNA was extracted from 3 lung adenocarcinoma cell lines that were fixed in LBC preservation solution using 2 protocols (one for cultured cells and one for tissues) of a DNA extraction kit. Different fixation times were tested for each protocol: 30 minutes, 1 hour, and 1 to 9 days. As controls, cells also were fixed in 10% formalin or 95% ethanol. The authors investigated the effect of fixation time on DNA fragmentation, polymerase chain reaction (PCR) amplification, and EGFR mutation detection.

RESULTS

The DNA yield of LBC specimens tended to decrease depending on fixation time. When using the DNA extraction protocol for tissues, PCR amplification was successful after 9 days of fixation, although extracted genomic DNA that was fixed for >1 hour demonstrated fragmentation. Mutation analyses using the Cycleave PCR method were successful after 7 days of fixation. The DNA extraction protocol for tissues was appropriate for lung adenocarcinoma cell lines that were stored for >1 day in a preservative solution. The results of the current study demonstrated that EGFR mutations can be detected on day 7 using lung adenocarcinoma cell lines fixed in CytoRich Red preservative.

CONCLUSIONS

When LBC specimens are used for targeted molecular genetic testing, the appropriate preservative solution and extraction protocol first should be determined.

Glandular Cell Abnormalities on SurePath Preparations: A Retrospective Review with Cytology-Histology Correlations

OBJECTIVE

Detecting glandular lesions is challenging by all Pap test methodologies. As the availability of data on identifying glandular abnormalities by SurePath is scarce, we investigated the detection rates and the correlation with histology follow-up.

STUDY DESIGN

A total of 105,927 cases (SurePath and conventional) were searched for the diagnosis of atypical glandular cells or higher glandular abnormalities (AGC+) with the corresponding histologic diagnosis. The associations between the Pap test methods and diagnostic categories were assessed by χ2 test.

RESULTS

Overall, 0.32% of SurePath (159/49,375) and 0.29% of conventional (164/56,552) cases showed AGC+ (p = 0.38). Histology confirmed significant abnormalities in 42 versus 53.5% of the cases, respectively (p = 0.064); 72.7% (SurePath) versus 65.2% (conventional) of these were glandular in nature (p = 0.37). The diagnosis of neoplasia (favored or definitive) showed malignancy on follow-up in 100% of SurePath cases (12/12). In contrast, 82.1% of these conventional cases disclosed premalignant or malignant lesions by histology (p = 0.12).

CONCLUSIONS

AGC+ cases showed higher prevalence on SurePath preparations. Conventional cases had more abnormalities on follow-up, while glandular lesions represented a higher proportion of abnormal histologies following SurePath AGC+s. The positive predictive value of favored or definite neoplasia was higher in SurePath cases. Overall, these differences were not statistically significant.

Diagnostic efficacy of liquid-based cytology for solid pancreatic lesion samples obtained with endoscopic ultrasound-guided fine-needle aspiration: Propensity score-matched analysis

BACKGROUND AND AIM

There is a paucity of data on the diagnostic efficacy of liquid-based cytology (LBC) for pancreatic samples obtained by endoscopic ultrasound-guided fine-needle aspiration (EUS-FNA). Using propensity score matching, we retrospectively analyzed the additional diagnostic value of LBC compared to a conventional Papanicolaou smear (CPS) for samples of solid pancreatic lesions obtained by EUS-FNA.

METHODS

This cohort study included 126 matched patients who underwent initial EUS-FNA for solid pancreatic lesions between January 2009 and August 2014. CPS was used for cytology of EUS-FNA samples obtained until May 2012 (63 patients). Subsequently, LBC was used for cytological analysis (63 patients). Diagnostic yields of CPS and LBC for malignancy were compared. Risk factors for cytological misdiagnosis with LBC were investigated.

RESULTS

Overall rate of malignancy was 86% after matching. LBC had higher diagnostic sensitivity and accuracy than CPS (96.6% vs 84.0%, P = 0.03; and 96.8% vs 87.3%, P = 0.05). LBC was significantly more sensitive for diagnosing pancreatic head lesions (96.4% vs 78.1%, P = 0.04). The sensitivity for pancreatic ductal adenocarcinoma (PDAC) with LBC was higher (98.1% vs 83.0%, P = 0.009). Multivariate analysis revealed that malignant tumors other than PDAC (P = 0.004) and lesion size ≤20 mm (P = 0.046) were risk factors for LBC misdiagnosis in all participants.

CONCLUSIONS

For solid pancreatic lesions, LBC of EUS-FNA samples contributes to the diagnosis of malignancy. Malignant tumors other than PDAC and small tumors are difficult to diagnose using EUS-FNA and LBC.

A comparison of liquid-based cytology with conventional Papanicolaou smears in cervical dysplasia diagnosis

Background:

Due to the high number of women affected by cervical cancer and the importance of an early diagnosis, combined with the frequent incidence of false-negative Papanicolaou (Pap) smear screening results for this disease, several studies have been conducted in recent years in order to find better tests. Liquid-based cytology (LBC) tests, including the liquid-based thin layer method, have demonstrated the highest potential for reducing false-negative cases and improved sample quality. This study aimed to compare the strength of the Pap smear test with fluid cytology and conventional tests in detecting cervical dysplasia.

Materials and Methods:

This descriptive-analytic study was conducted on 366 women who attended private laboratories for a Pap smear. The Pap smear sampling was conducted simultaneously using two methods: conventional Pap (CP) smear and LBC), from the cervix.

Results:

The mean age of the participants was 32 ± 8.8 years. Diagnostic results of endocervical cells, epithelial cells, vaginitis cells, and metaplastia were consistent with both conventional and liquid cytology smears, and the kappa coefficient was determined to be significant (P < 0.001). In total, 40.5% of diagnostic cases indicated bacterial inflammation 80.3% of the diagnoses in both methods were P1 and 3.9% of cases diagnosed were P2, the overall diagnostic consistency was 83.9% between the two sampling methods. The inflammation diagnosis was 40.5% and this was consistent in both methods of LBC and CP. There was one case of a false-negative diagnosis in the LBC method and 14 cases in the CP method.

Conclusion:

Results showed that the LBC may improve the sample's quality and reduce the number of unsatisfactory cases more than with the CP method.

A comparative analysis of conventional and SurePath liquid-based cervicovaginal cytology: A study of 140 cases

Background:

The role of Papanicolaou (Pap) test in cervical cancer screening need not be overemphasized. While most Western countries have adopted the liquid-based cytology (LBC), which is considered superior, many developing countries are still using the conventional Pap smear (CPS) technique.

Objective:

To compare the staining and cytomorphological features on conventional versus liquid-based cervicovaginal smears.

Materials and Methods:

One hundred and forty cervicovaginal smears prepared by the standard conventional and LBC techniques were interpreted as per the Bethesda system of reporting cervicovaginal smears. Twelve parameters were studied, compared, and statistically analyzed. A P value <0.05 was considered to be statistically significant.

Results:

129/140 (92%) of CPSs and 130/140 (93%) LBC smears were satisfactory. LBC had a significantly shorter screening time (2.0 ± 0.08 vs 4.0 ± 0.65) and better representative material than that of CPS (50% vs 42%). Neutrophils were significantly more in CPS than LBC (96% vs 92%) with a P value <0.05 while hemorrhagic background and red blood cells (RBCs) were more prominent in CPS. LBC showed significant artifactual changes in squamous epithelial cells. Epithelial abnormalities ranging from atypical squamous cells of undetermined significance (ASCUS) to high grade squamous intraepithelial lesion (HSIL) were seen in 3% (4) and 2% (2) of CPSs and LBCs, respectively. Organisms were better picked up in CPS (99% in CPS vs 73% LBC) with a value of P = 0.0001.

Conclusion:

Although a shorter screening time and cleaner background are the major advantages of LBC, CPS is not inferior to LBC. Considering the high cost, rather than the advantages associated with LBC, we feel that CPS is a better option for developing countries.

The advantages of incorporating liquid-based cytology (TACAS™) in mass screening for cervical cancer

We incorporated liquid-based cytology (LBC) in population-based screening for cervical cancer. The usefulness of using LBC in mass screening for cervical cancer was examined. From 2009 to 2014, 157,061 individuals underwent mass screening for cervical cancer in Aomori Prefecture. From 2009 to 2011, cells were collected from 82,218 individuals and the specimens were conventionally prepared (CP). From 2012 to 2014, cells were collected from 74,843 individuals and the specimens were prepared using LBC (TACAS™). Cytology results for the 2 sets of specimens were compared and differences in cytologic features were examined. ASC-US and more severe lesions were detected at a rate of 1.13 % by CP and 1.44 % by LBC, so LBC had a 1.3-fold higher rate of detection. LBC had a 1.6-fold higher rate of LSIL detection and a 1.2-fold higher rate of HSIL detection. CP detected cancer in 20 cases at a rate of 0.024 % while LBC detected cancer in 18 cases at a rate of 0.024 %. Cytodiagnosis of the 18 cases of SCC that LBC identified revealed that 7 were SCC, 8 were HSIL, and 3 were ASC-H. Atypical cells tended to be smaller with TACAS™. LBC reduced the time needed for microscopic examination of a single specimen by 42 % in comparison to CP. LBC using TACAS™ allowed the detection of slight lesions and slight changes in cells. LBC can lessen the burden on medical personnel and may lead to improved accuracy.

Comparing SurePath, ThinPrep, and conventional cytology as primary test method: SurePath is associated with increased CIN II+ detection rates

Purpose

Within the last decade, SurePath and ThinPrep [both liquid-based cytology (LBC) tests] have replaced conventional cytology (CC) as primary test method in cervical cancer screening programs of multiple countries. The aim of our study was to examine the effect in the Dutch screening program.

Methods

All primary smears taken within this program from 2000 to 2011 were analyzed using the nationwide registry of histo- and cytopathology (PALGA) with a follow-up until March 2013. The percentage of smears classified as borderline/mildly dyskaryotic (BMD) and >BMD as well as CIN and cervical cancer detection rates were compared between SurePath and ThinPrep versus CC by logistic regression analyses (adjusted for age, screen region, socioeconomic status, and calendar time).

Results

We included 3,118,685 CC, 1,313,731 SurePath, and 1,584,587 ThinPrep smears. Using SurePath resulted in an increased rate of primary smears classified as >BMD [odds ratio (OR) = 1.12 (95% confidence interval (CI) 1.09–1.16)]. CIN I and II⁺ detection rates increased by 14 % [OR = 1.14 (95% CI 1.08–1.20)] and 8 % [OR = 1.08 (95% CI 1.05–1.12)]. Cervical cancer detection rates were unaffected. Implementing ThinPrep did not result in major alterations of the cytological classification of smears, and it did not affect CIN detection rates. While not significant, cervical cancer detection rates were lower [OR = 0.87 (95% CI 0.75–1.01)].

Conclusions

The impact of replacing CC by LBC as primary test method depends on the type of LBC test used. Only the use of SurePath was associated with increased CIN II⁺ detection, although it simultaneously increased the detection of CIN I.

Comparison of conventional Papanicolaou cytology samples with liquid-based cervical cytology samples from women in Pernambuco, Brazil

In the present study, we compared the performance of a ThinPrep cytological method with the conventional Papanicolaou test for diagnosis of cytopathological changes, with regard to unsatisfactory results achieved at the Central Public Health Laboratory of the State of Pernambuco. A population-based, cross-sectional study was performed with women aged 18 to 65 years, who spontaneously sought gynecological services in Public Health Units in the State of Pernambuco, Northeast Brazil, between April and November 2011. All patients in the study were given a standardized questionnaire on sociodemographics, sexual characteristics, reproductive practices, and habits. A total of 525 patients were assessed by the two methods (11.05% were under the age of 25 years, 30.86% were single, 4.4% had had more than 5 sexual partners, 44% were not using contraception, 38.85% were users of alcohol, 24.38% were smokers, 3.24% had consumed drugs previously, 42.01% had gynecological complaints, and 12.19% had an early history of sexually transmitted diseases). The two methods showed poor correlation (k=0.19; 95%CI=0.11–0.26; P<0.001). The ThinPrep method reduced the rate of unsatisfactory results from 4.38% to 1.71% (χ²=5.28; P=0.02), and the number of cytopathological changes diagnosed increased from 2.47% to 3.04%. This study confirmed that adopting the ThinPrep method for diagnosis of cervical cytological samples was an improvement over the conventional method. Furthermore, this method may reduce possible losses from cytological resampling and reduce obstacles to patient follow-up, improving the quality of the public health system in the State of Pernambuco, Northeast Brazil.

A Comparison Between ThinPrep Monolayer and Cytospin Cytology for the Detection of Bladder Cancer

Purpose

The sensitivity of urine cytology is higher for carcinoma in situ and poorly differentiated tumors in bladder cancer, while being fairly low for low-grade or well-differentiated tumors. Development of a sensitive diagnostic test to detect bladder carcinoma would significantly facilitate patient management and allow earlier treatment of this disease. This study compared ThinPrep urine cytology (Cytyc Co.) and conventional Cytospin urine cytology (Shandon Scientific Ltd.) in the diagnosis of bladder cancer.

Materials and Methods

From January 2002 to December 2010, ThinPrep cytology and conventional urine Cytospin cytologic examination of bladder washings were performed in 3,085 subjects suspected of having bladder cancer and in 379 patients with follow-up after transurethral resection of bladder tumor (TUR-BT). The sensitivity and specificity of the urine ThinPrep test was compared with that of conventional Cytospin cytology according to tumor number, size, pathological stage, grade, and recurrence.

Results

Of 3,085 subjects, bladder cancer was confirmed by TUR-BT in 379 subjects. The overall sensitivity of ThinPrep and Cytospin cytology was 60.9% and 59.9% in patients suspected of having bladder cancer, respectively. The overall specificity of ThinPrep and Cytospin cytology was 94.8% and 95.3% in patients suspected of having bladder cancer, respectively. The sensitivity of ThinPrep and Cytospin cytology was increased with increasing number, size, pathological stage, and grade, but there was no significant difference between the two tests.

Conclusions

These results suggest that ThinPrep cytology has no advantage in the diagnosis of bladder cancer of a low grade or low stage.

Molecular Basis for Advances in Cervical Screening

Human papillomaviruses (HPVs) cause cervical lesions, which can, in some instances, progress to high-grade neoplasia and cancer. Around half a million cases of cervical cancer occur each year, with most occurring in developing countries where cervical cancer is a major cause of cancer-related death. The reduction in cervical cancer incidence in developed countries is largely attributed to the introduction of cervical screening. Cervical screening currently depends on the identification by cytology of abnormalities in cells taken from the surface of the cervix. The standard Pap test was developed >50 years ago, and despite modifications, still forms the basis of the test currently in use in most routine screening laboratories. Advances in our understanding of the molecular mechanisms that lead to the development of cervical cancer have been slow to impact on screening, despite the relatively high false-negative rates that can be associated with the conventional Pap smear. Improvements in screening strategies fall into a number of categories. Methods that improve cell presentation and attempt to eliminate artefacts/obscuring debris can be combined with image analysis systems in order to enhance diagnostic accuracy. Such approaches still rely on cytological evaluation and do not incorporate advances in our knowledge of how HPV causes cancer. By contrast, markers of virus infection or cell cycle entry, particularly those that offer some degree of prognostic significance, may be able to highlight abnormal cells more reliably than cytology, and could be combined with cytology to improve the detection rate. Our understanding of the molecular biology of HPV infection and the organization of the HPV life-cycle during cancer progression provides a rational basis for marker selection. The general assumption that persistent active infection by high-risk HPV types is the true precursor of cervical cancer provides the rationale for HPV DNA testing in conjunction with enhanced cytology, while the development of RNA-based approaches should allow active infections to be distinguished from those that are latent. The detection in superficial cells of marker combinations at the level of RNA or protein has the potential to predict disease status more precisely than the detection of markers in isolation. There is also a need for better prognostic markers if the predictive value of screening is to be improved. The potential to control infection by vaccination should reduce the incidence of HPV-associated neoplasia in the population, and this may cause a change in the way that screening is carried out. Nevertheless, the lack of a therapeutic vaccine, and the difficulties associated with eliminating infection by multiple high-risk HPV types, means that some form of screening will still be required as a preventive measure for the control of cervical cancer for the foreseeable future.

Gynecologic cytology on conventional and liquid-based preparations: a comprehensive review of similarities and differences

Liquid-based preparations (LBPs) have largely replaced conventional Papanicolaou smears (CPS) for cervical samples in the United States and in many other industrialized countries. The two FDA-approved LBP currently in use include ThinPrep (TP), (Hologic Inc., Bedford, MA) and SurePath (SP), (BD Diagnostic, Burlington, NC). Split-sample and direct-to-vial studies have shown that LBPs show an overall improvement in sample collection and processing, reduce artifacts that interfere in diagnosis, are more sensitive, can be utilized for ancillary tests and are a cost-effective replacement for CPS. Comparative analyses of diagnostic accuracy indicate that LBPs perform at least as well as CPS. However, the added advantages of standardized, automated preparations and screening, reduced unsatisfactory rate, improved specimen adequacy and ability to perform human papillomavirus (HPV) test, are enough to continue use of LBP. The cytologic features in LBP are similar to CPS with subtle differences, particularly in background information. There are also subtle differences between the two LBPs, SP and TP, which are reflective of different sampling devices, collection media, and processing techniques. Architecturally, LBP shows smaller cell clusters and sheets and more dyscohesion. Cytologically, enhanced nuclear features and smaller cell size are more prominent. Advances in liquid-based Papanicolaou's (Pap) test have lead to well-defined patient management guidelines by the American Society for Colposcopy and Cervical Pathology. Herein, we review these aspects of Pap test including, morphology, automation, ancillary tests (HPV and immunochemistry), pertinent QA/QC monitors, patient management guidelines, and review of pertinent literature.

Unsatisfactory rates vary between cervical cytology samples prepared using ThinPrep and SurePath platforms: a review and meta-analysis

OBJECTIVE

To compare unsatisfactory rates between the two major liquid-based cytology (LBC) platforms, namely ThinPrep (Hologic) and SurePath (Becton Dickinson).

DESIGN

The authors performed both a systematic review and a meta-analysis. Inclusion criteria were English language, data presented on unsatisfactory rates for either ThinPrep or SurePath, utilising actual patient samples (ie, not laboratory manipulated samples) and no manipulation using acetic acid to increase the satisfactory rate. The authors searched PubMed for articles using the keywords 'SurePath' or 'ThinPrep' and 'unsatisfactory'. References of retrieved studies were searched for additional articles. Key researchers in the field were also contacted.

PARTICIPANTS AND INTERVENTIONS

Eligible studies were reviewed for rates of unsatisfactory cervical cytology smears processed on either the ThinPrep or SurePath platforms (compared with a general linear model) or data on unsatisfactory rates for both platforms for the same laboratory and the same patient population (compared with a meta-analysis using a random effects model and pooled RR).

PRIMARY OUTCOME MEASURE

Unsatisfactory rate of cervical cytology smears.

RESULTS

A total of 1 120 418 cervical cytology smears were reported in 14 different studies using the SurePath platform for an overall unsatisfactory rate (weighted average) of 0.3%. 28 studies reported on 1 148 755 smears prepared using the ThinPrep platform for an overall unsatisfactory rate (weighted average) of 1.3%. The general linear model did not show a difference between LBC platforms when other variables were controlled for; however, the power to detect a difference (0.087) was very low. The meta-analysis performed on four studies where both ThinPrep and SurePath results were reported from the same laboratory showed fewer unsatisfactory tests from the SurePath platform (RR 0.44, 95% CI 0.25 to 0.77, p=0.004).

CONCLUSIONS

Multiple factors affect LBC unsatisfactory rates. In a meta-analysis, cervical cytology samples prepared on the SurePath platform show significantly fewer unsatisfactory smears than those prepared on the ThinPrep platform.

Comparison of ThinPrep and SurePath liquid-based cytology and subsequent human papillomavirus DNA testing in China

BACKGROUND

Liquid-based cytology (LBC) has been compared with conventional cytology in numerous studies. In the current study of 2 LBC systems, the accuracy, rates of unsatisfactory cytology, and sufficiency of residual LBC specimens for Hybrid Capture 2 (HC2) HPV DNA testing were compared.

METHODS

Eligible women ages 30 to 49 years were recruited for this cross-sectional population-based study in rural China. Women were assessed by visual inspection with acetic acid (VIA), LBC, and high-risk HPV HC2 DNA assay. Cervical specimens were preserved according to SurePath or ThinPrep protocols. LBC results were manually read. HC2 testing was performed on specimens with sufficient residual volume. Colposcopies and biopsies were performed on women who were VIA positive at the time of initial screening. Women with abnormal LBC or HC2 test results were called back for colposcopies and 4-quadrant cervical biopsies.

RESULTS

Of 2005 eligible women, 972 were tested by SurePath and 1033 by ThinPrep. Compared with SurePath samples, ThinPrep samples had higher rates of unsatisfactory cytology (0.2% for SurePath and 1.5% for ThinPrep) and insufficient residual volume for HC2 (0.0% for SurePath and 18.2% for ThinPrep). SurePath samples yielded higher sensitivities and similar specificities for LBC and HC2 testing of residual specimens, but these differences were not determined to be significant by area-under-the-curve analysis (LBC performance: 0.89 for SurePath and 0.85 for ThinPrep; HC2 performance: 0.91 for SurePath and 0.89 for ThinPrep).

CONCLUSIONS

Both methods yielded similar validity in detecting significant cervical lesions. However, SurePath samples yielded higher rates of satisfactory LBC slides and sufficient residual volume for HC2.

Efficacy of Abbott RealTime High Risk HPV test in evaluation of atypical squamous cells of undetermined significance from an Asian screening population

BACKGROUND

Abbott RealTime High Risk HPV test is a new qualitative real-time PCR assay for the detection of 14 high risk HPV (HR-HPV) types and specific identification of HPV16 and HPV18. For each new HPV DNA test, it is important to validate its clinical performance using established tests as benchmarks. Hybrid Capture 2 (HC2) is the first USA FDA-approved HR-HPV DNA test.

OBJECTIVES

To compare the performance of Abbott RealTime High Risk HPV test with that of Hybrid Capture 2 in detecting cytology samples with varying prognosis.

STUDY DESIGN

250 liquid-based cervical cytology samples diagnosed of Atypical Squamous cells of Undetermined Significance (ASC-US) collected from an Asian Screening Population were independently tested with both Abbott RealTime High Risk HPV test and HC2. Their utility in predicting disease progression was evaluated in 82 of the samples for which follow up cytology or colposcropic histology data was available.

RESULTS

Good to excellent agreement between the two tests was demonstrated (Kappa=0.800, 95% CI: 0.726-0.874). The sensitivity, specificity, positive (PPV) and negative predictive values (NPV) of the two tests in detecting cases with underlying HSIL/CIN2+ were evaluated (Abbott: 100%, 20.83%, 14.93% and 100% respectively; HC2: 100%, 12.50%, 13.70% and 100% respectively). HPV16/18 genotyping provided by the Abbott test enhanced specific identification of cases with LSIL/CIN1+ (specificity 91.30%, PPV 84.62%) and HSIL/CIN2+ (specificity 86.11%, PPV 23.08%) at follow-up.

CONCLUSIONS

The Abbott test performed similarly to HC2 and is unlikely to be affected by ethnicity. Abbott combined HPV detection and HPV 16/18 genotyping is found to provide enhanced sensitivity and specificity for triage of ASC-US.

Atypical glandular cells diagnosed during pregnancy and the postpartum period: a retrospective analysis

OBJECTIVES

The objective of the study was to determine the prevalence and clinical significance of atypical glandular cells (AGC) or atypical glandular cells of undetermined significance (AGUS) diagnosed in pregnant and postpartum women.

STUDY DESIGN

Smears having a diagnosis of AGC or AGUS, taken from pregnant and postpartum (within six weeks after delivery) women between 1995 and 2008 were reviewed and subclassified according to the Bethesda 2001 classification. Case records were then reviewed and a second cytology review was performed after disclosure of the follow-up data.

RESULTS

Among 91,133 smears taken from pregnant and postpartum women, 70 had AGC or AGUS (0.07%) diagnosed. Follow-up data were available in 40 cases, with mean duration of follow-up being 43 months. Among the 40 patients with follow-up data, nineteen had smears with coexisting squamous abnormalities. Thirty patients had positive pathology, including 18 (45%) cervical intraepithelial neoplasia III (CIN III), four (10%) cervical adenocarcinoma-in situ, three (7.5%) squamous cell carcinoma of cervix, four (10%) condylomas and one (2.5%) hydatidiform mole. On review, 24 out of 32 smears with AGC 'not otherwise specified' ('NOS') had significant pathology.

CONCLUSIONS

AGC found on cervical smears during pregnancy and the postpartum period is uncommon. The chance of having significant cervical pathology, however, is high and colposcopy should be performed.

P634A4 and TAp73 immunocytochemistry in liquid-based cervical cytology--potential biomarkers for diagnosis and progress prediction of cervical neoplasia

P63 and p73 are two homologues of the important tumor suppressor gene p53. In this study, we investigated p63 and p73 expression by immunocytochemistry using antibodies for TAp73 and p634A4 isoforms in 91 high-grade and 107 low-grade squamous intraepithelial lesions, 212 atypical squamous cells of undetermined significance, 9 squamous cell carcinomas and 63 normal samples from an Asian screening population together with 47 hospital samples of carcinomas. There was significant correlation between the TAp73 and p634A4 indices (P<0.0001). Significantly, higher TAp73 and p634A4 indices were found in high-grade lesions or carcinoma when compared with atypical squamous cells and low-grade lesions (P<0.0001). Among atypical squamous cells, p634A4 indices of cases that subsequently progressed to low-grade (P=0.031) or high-grade lesions (P=0.006) were significantly higher than those that did not. For atypical squamous cells positive for high-risk human papillomavirus (HPV) as detected by Digene (61%), cases with high p634A4 index were still more likely to have subsequent high-grade lesions detected (P=0.016). Among low-grade lesions, significantly higher TAp73 (P=0.038) was found in cases that subsequently progressed to high-grade lesions. There was significant correlation between presence of high-risk HPV and p634A4 index (P=0.01). In summary, p63 and p73 immunocytochemistry are potential good markers for detection of carcinoma and high-grade lesions in cervical cytology samples and for triage management of women with atypical squamous cells and low-grade lesions.

Image-guided ThinPrep Papanicolaou tests and cotesting with high-risk human papillomavirus in women aged 30 years and older in a low-risk private practice population

BACKGROUND

Screening for cervical cancer precursors has evolved considerably with the introduction of new technologies to improve the early detection of disease. The objective of this study was to analyze the accuracy and effectiveness of combined screening with cytology and high-risk human papillomavirus (HR-HPV) testing in a low-risk population of women aged >or=30 years.

METHODS

Consecutive unselected samples from a group of 1871 women aged >or=30 years were screened with image-guided ThinPrep tests and HR-HPV tests during a 6-month period. Histologic follow-up was reviewed among women with positive HR-HPV tests.

RESULTS

A total of 85 (4.5%) women had positive HR-HPV tests. In 48 HR-HPV-positive women with follow-up biopsies, 41 (85%) were found to have histologic abnormalities. Thirty-three (1.9%) women with cytologically normal Papanicolaou (Pap) tests harbored HR-HPV, and a cervical intraepithelial neoplasia (CIN) 2+ lesion was detected in 1 (16%) of 6 women with histologic follow-up. Conversely, 2 (28%) of 7 women with high-grade intraepithelial lesion on cytology tested negative for HR-HPV during the same period. A case of serous carcinoma with atypical glandular cells on cytology was also negative for HR-HPV, as expected.

CONCLUSIONS

In this low-risk population of women aged >or=30 years, histology-confirmed CIN2+ lesions were identified in women with negative cytology and positive HR-HPV tests, as well as in those with positive cytology and negative HR-HPV tests. Because both cytology and HPV testing alone missed significant lesions, cotesting with Pap and HR-HPV in women aged >or=30 years appears to be a reasonable option in a low-risk population.

Results of a cervical cancer screening programme from an area of Barcelona (Spain) with a large immigrant population

BACKGROUND

To assess the participation rate and results of cytological assessment in the context of cervical cancer screening activities in an area of Barcelona (Spain) with a large immigrant population.

METHODS

Descriptive retrospective study of cytologies performed between 2001 and 2006 in women > or =14 years of age living in 2 out of 10 districts of Barcelona (n = 129 327) and participating in cervical cancer screening activities within a sexual and reproductive health care programme.

RESULTS

Between 2001 and 2006, overall participation among women aged 20- to 64-years old was 50.7%, with higher participation among women aged 20-34 years than among those aged 50-64 years (63.8 and 36.0%, respectively; P < 0.01). The median frequency was 0.5 cytologies/year. The rate of pathological results increased from 11.4 per thousand in 2001 to 29.0 per thousand in 2006 (P < 0.001). This increase was higher among younger women and was mainly due to an increase in the rate of atypical squamous cells of undetermined significance (ASCUS) and low-grade squamous intraepithelial lesions (L-SIL).

CONCLUSIONS

These results show a low rate of participation in the public cervical cancer screening programme and an increase in the number of pathological results during the study period. These results provide useful information at a time when significant changes in the prevention of cervical cancer are being planned.

Superior performance of liquid-based versus conventional cytology in a population-based cervical cancer screening program

OBJECTIVE

Liquid-based cytology may offer improvements over conventional cytology for cervical cancer screening. The two cytology techniques were compared in a group of 86,469 women who participated in a population-based screening program. Using a nation-wide pathology database containing both cervical cytology and histology records for all patients, we compared the outcome of the two screenings methods with regard to the detection rate of histological proven abnormalities and the determination of the true false-negative rates for both methods.

METHODS

Two cohorts of women living in the same geographical region were used. Cohort 1 (n=51,154 women) was analysed using conventional cytology (conventional cohort) and cohort 2 (liquid cohort) (n=35,315 women) was analysed using liquid-based cytology (SurePath). The samples were processed in one laboratory. The results of histological follow up were available via a central database.

RESULTS

The rate of unsatisfactory slides was significantly lower using liquid-based cytology (0.13% vs. 0.89%, p<0.0001). Detection of ASCUS+ (Atypical squamous cells of unknown significance or higher abnormalities) was significantly higher using liquid-based cytology (2.97% vs. 1.64%, p<0.0001), mainly due to the increase in the ASCUS category. The percentage of histological abnormalities within the ASCUS samples was approximately equal in both cohorts, indicating that more true abnormal cases were detected using liquid-based cytology. The sensitivity for detection of a histological proven lesion is significantly higher in the liquid cohort compared to the conventional cohort (96.2% vs. 92.0%), with only a slight difference in specificity (97.8% vs. 98.2%).

CONCLUSION

This population study confirmed previous institution-based reports of decreased numbers of unsatisfactory samples based on liquid-based cytology and showed an increased sensitivity for the detection of cytological abnormalities that was validated by subsequent histological investigation.

Who receives, benefits from and is harmed by cervical and breast cancer screening among Hong Kong Chinese?

BACKGROUND

To estimate the proportion of and characterize women who had received cervical and breast screening and to quantify the associated preventable burden of disease and potential iatrogenic harm.

METHODS

A total of 3484 Hong Kong Chinese women were interviewed in person. Screening prevalence and associated predictors, disability-adjusted life-years (DALYs), the numbers of false-positive tests and the resultant confirmatory procedures and related complications were estimated.

RESULTS

A total of 6.2% of women (>or=18) reported regular pap but no mammography or clinical breast examination (CBE) as per local evidence-based guidelines, whereas among women aged >or=40 years, 5.2% reported regular screening by all three modalities and 55.3% had never been screened for either cancer. Women who underwent regular health checkups were consistently the most likely to have been screened, as were younger, married and socially advantaged respondents. Triennial pap screening would save 708 DALYs annually, or 528 more DALYs compared with the status quo. However, this would generate 28,600 repeat smears and 390 colposcopies from false-positive screens. Opportunistic mammographic screening averted 100 DALYs currently, but could have potentially reduced a further 546 with biennial screening. Mass screening mammography (CBE) would lead to 33,700 (20,200) false-positives per year requiring 29,900 (8300) repeat mammograms or ultrasonograms, 6800 (3000) biopsies and 620 (270) biopsy-related complications.

CONCLUSIONS

Screening uptake patterns are suboptimal. By making explicit the possible risks and benefits based on this template, policy makers in developing Asia with a similar female cancer burden may be able to use the information to make evidence-based decisions that are consistent with local circumstances, values and preferences.

Accuracy of herpes simplex virus detection in liquid-based (SurePath) Papanicolaou tests: a comparison with polymerase chain reaction

A review of our institution's Papanicolaou test records over an 11-yr period showed that liquid-based Papanicolaou tests (LBPTs) had a significantly higher frequency of diagnoses of Herpes simplex virus (HSV)-related cellular changes compared to conventional Papanicolaou smears (77/302,841, 0.026% vs. 56/376,173, 0.015%, P = 0.002). To investigate the accuracy of the diagnosis of HSV by LBPT, we performed conventional polymerase chain reaction (PCR) on the residual samples from 258 prospectively collected LBPT and real-time PCR using a different primer set on a subset of 40 LBPT. Conventional PCR was positive in 22 of 22 cases diagnosed of HSV, 1 of 2 cases diagnosed as suspicious for HSV, and none of 234 LBPT without a cytologic HSV diagnosis. Real-time PCR was positive in 8 of 8 cases diagnosed as HSV and none of the 32 controls. We conclude that LBPT allows an increased detection of HSV that is highly accurate.

ThinPrep are superior to conventional smears in the cytological diagnosis of subfertile men by testicular fine-needle aspiration

The aim of this study was the comparison of liquid-based cytology (ThinPrep, TS) to conventional smears (CS) in the investigation of subfertile men with testicular fine-needle aspiration (FNA). Between January and December 2004, testicular FNA biopsies were performed in 30 subfertile men. Both TS and CS were diagnosed according to Meng classification. Features specifically recorded in each smear included sample adequacy, tissue cells preservation, contamination with red blood cells, quality of smear background, ease of cell recognition, and the cytological diagnosis. There was agreement in the cytological diagnosis between TS and CS (P = 0.88) and sample adequacy (P = 0.73). TS was superior to CS regarding cell preservation, presence of red blood cells or tissue artifacts, quality of the smear background, and cell recognition (P < 0.0001). In testicular FNA cytology, TS appear to be superior to CS in respect to cell preservation, absence of red blood cells, background quality, and cell recognition. These advantages, however, are not translated in improved cytological diagnosis.

Evaluation of agreement between conventional and liquid-based cytology in cervical cancer early detection based on analysis of 2,091 smears: experience at the Brazilian National Cancer Institute

The aim of this work was to evaluate the agreement between conventional cytology (CC) and liquid-based cytology (LBC) in cervical cancer early detection. The results of CC and LBC (DNACitoliq in 2,059 women aged 25-59 years were compared. The percent agreement, kappa coefficient, prevalence-adjusted bias-adjusted kappa coefficient (PABAK), and Chamberlain's percent positive agreement (PPA) were calculated. The percent agreement between the two methods was very good (80% and 79%, respectively, for normal versus ASCUS+; and normal versus ASCUS, AGUS and LSIL+ vs. HSIL+). The kappa coefficient indicates slight agreement (0.26 and 0.23, respectively), but when PABAK was used the agreement was good (0.61 and 0.68, respectively). PPA was high for normal results (79.2%) and low for the remaining categories. To conclude, in this study, agreement between LBC and CC was only good for normal results, which involves the majority of cases and positively influences the overall agreement rate.

Barriers to adoption of recent technology in cervical screening

The Pap smear is one of the modern success stories in the field of preventive medicine. Since its introduction as a screening test, there has been a dramatic reduction in the incidence of cervical cancer. However, the search for a better screening test continues. The new technologies, including liquid-based cytology (LBC), Human Papilloma Virus (HPV) testing and automated or machine-assisted screening have been introduced. However, there is continuous debate about whether society's limited resources are better spent on reaching the underserved rather than on these technologies. Another question is whether these technologies create yet another kind of disparity in delivering preventive care. For example, despite the wide use of LBC (99% of tests submitted to our laboratory are LBC), conventional Pap smears are still used to screen/follow up some women. It is not clear why some providers continue to prefer conventional smear over LBC and what are the barriers for adopting LBC in cervical cancer screening. We hypothesize the lower cost of conventional compared to LBC Pap testing, patient's lower socio-economic indices, a patient's medical history and provider's subspecialty/training all appear to play a role in the choice of using conventional Pap testing rather than LBC. Unintentionally, this choice results in repeat testing, delayed treatment and potentially higher costs than intended. The ultimate goal of this review article is to understand and explore possible barriers and disparities to adopting new technology in cancer screening.

Ontario Cervical Cancer Screening Clinical Practice Guidelines

OBJECTIVE

To develop clinical practice guidelines for cervical screening and the primary management of abnormal cytology in Ontario, using an established methodological process.

DATA SOURCES

Primary data sources were relevant articles listed in the Medline (1998 to July 2004), Embase (1998 to July 2004), and Cochrane Library (2004, Issue 2) databases.

STUDY SELECTION

Studies addressing quality or the optimization of cervical screening were considered eligible in the systematic review of the evidence. Specifically, clinical practice guidelines, technology assessments, systematic reviews, and randomized controlled trials were of primary interest. Given the variability of the data, other information sources were considered eligible if there was a demonstrated gap in the published literature.

DATA EXTRACTION

Data were identified and extracted by a methodologist and reviewed by four authors. Results were reviewed and discussed by members of an expert working group consisting of a diverse group of health professionals with expertise in cervical cancer. Data audits were conducted by independent reviewers.

DATA SYNTHESIS

recommendations with evidence ratings were developed through a review of the evidence with expert consensus and were approved by more than 80% of 40 external practitioners who reviewed the document and responded to a standardized survey.

CONCLUSION

The development of comprehensive recommendations on cervical screening in Ontario was feasible using a rigorous methodological process. Recommendations for practice are provided.

Cervical cytology reading times: A comparison between thinprep imager and conventional methods

We aimed to compare the times cytologists spend reviewing cervical cytology slides processed by the ThinPrep Imager (TPI) with times they spend examining conventional cytology (CC) slides. We also aimed to examine the effect of cytologists' experience on reading times. Using a cross-sectional analytical design, we analyzed routine laboratory data, collected retrospectively over 7 months, for 41 cytologists, including paired data for 20 who read both TPI and CC slides. For the 20 cytologists who read both types of cytology, the mean reading rate was 13.3 slides per hour for TPI slides and 6.1 slides per hour for CC slides. The mean within-reader difference between TPI and CC rates was 7.2 slides per hour (P < 0.001). For CC reading, mean times did not differ between those who were additionally trained to read TPI slides and those who only read CC. Slower readers had greater increases in speed when using the TPI compared with CC reading than did faster readers (P < 0.001). More experienced cytologists tended to read CC slides more quickly than did those less experienced, but experience did not affect TPI reading times or within-reader differences in reading times between cytology types. The TPI significantly reduced reading times compared with CC. This reduction was greater amongst slower readers, and was unrelated to experience.

A comparative study of two devices used for cervical cell sampling raises some doubts about liquid-based cytology

The objective of this study was to compare the quality of smears obtained by a newly designed cervical cell sampler (the implement) to those obtained with the cervex brush, using liquid-based cytology (LBC). A prospective randomized controlled trial with the approval of the local ethics committees after informing the Medical Devices Agency in the UK was used in this study. The study was carried out in colposcopy clinics in two district general NHS Trust Hospitals in London. A total of 200 women were recruited (100 from each hospital). The women were randomized into two groups, each of them having two smears at the same time. One hundred (50%) of the women had their first smear with the new implement, and the other 100 (50%) had their first smear with the cervex brush. The main outcome of this study is good-quality smears, assessed by evidence of effective sampling of the transformation zone, including immature metaplastic cells and also endocervical cells. Eighty-five percent of the smears taken by the new implement showed good-quality smears compared to 91% of those taken by the cervex brush, a statistically marginally nonsignificant result, with P value = 0.052 (McNemar exact test). A larger number of good-quality smears, judged by evidence of sampling of transformation zone, were obtained with the cervex brush, though the difference was statistically marginally nonsignificant, using the British society for clinical cytology criteria. Surprisingly, despite the use of LBC, there was a higher rate of inadequate smears obtained with both the devices (8% with each) compared to our previous study using the conventional slide test (1.3% with the new implement and 1.8% with the Jordan's spatula).

Human Papillomavirus Testing and Liquid-Based Cytology: Results at Recruitment From the New Technologies for Cervical Cancer Randomized Controlled Trial

BACKGROUND

Although testing for human papillomavirus (HPV) has higher sensitivity and lower specificity than cytology alone for detecting cervical intraepithelial neoplasia (CIN), studies comparing conventional and liquid-based cytology have had conflicting results.

METHODS

In the first phase of a two-phase multicenter randomized controlled trial, women aged 35-60 years in the conventional arm (n = 16,658) were screened using conventional cytology, and women in the experimental arm (n = 16,706) had liquid-based cytology and were tested for high-risk HPV types using the Hybrid Capture 2 assay. Women in the conventional arm were referred to colposcopy with atypical cells of undetermined significance (ASCUS) or higher and those in the experimental arm were referred with ASCUS or higher cytology or with a positive (> or = 1 pg/mL) HPV test. Sensitivity and positive predictive value (PPV) for detection of cervical intraepithelial neoplasia grade 2 or higher (CIN2+) were calculated.

RESULTS

The screening methods and referral criterion applied in the experimental arm had higher sensitivity than that in the conventional arm (relative sensitivity = 1.47; 95% confidence interval [CI] = 1.03 to 2.09) but a lower PPV (relative PPV = 0.40; 95% CI = 0.23 to 0.66). With HPV testing alone at > or = 1 pg/mL and at > or = 2 pg/mL, the gain in sensitivity compared with the conventional arm remained similar (relative sensitivity = 1.43, 95% CI = 1.00 to 2.04 and relative sensitivity = 1.41, 95% CI = 0.98 to 2.01, respectively) but PPV progressively improved (relative PPV = 0.58, 95% CI = 0.33 to 0.98 and relative PPV = 0.75, 95% CI = 0.45 and 1.27, respectively). Referral based on liquid-based cytology alone did not increase sensitivity compared with conventional cytology (relative sensitivity = 1.06; 95% CI = 0.72 to 1.55) but reduced PPV (relative PPV = 0.57; 95% CI = 0.39 to 0.82).

CONCLUSIONS

HPV testing alone was more sensitive than conventional cytology among women 35-60 years old. Adding liquid-based cytology improved sensitivity only marginally but increased false-positives. HPV testing using Hybrid Capture 2 with a 2 pg/mL cutoff may be more appropriate than a 1 pg/mL cutoff for primary cervical cancer screening.

Liquid-based cytology improves productivity in cervical cytology screening

OBJECTIVES

The ThinPrep test was introduced into our institution on a phased basis over 3 years between January 2002 and December 2004. This study set out to assess its effect on productivity (as measured by output of cases per medical scientist per day) during the changeover period. Numbers of high and low-grade lesions and of unsatisfactory slides were also monitored.

METHODS

The percentage conversion from conventional preparation to liquid-based cytology (LBC) and output of cases per medical scientist per day were calculated from our database at 6-month intervals. The average backlog, average number of cases received per month and percentage of unsatisfactory and abnormal cases were calculated similarly.

RESULTS

Over the study period 92 084 cases were received. The percentage of cases using ThinPrep increased: from 9% in January 2002 to 73% in December 2004. During the study there was an increase in output from 17.0 to 22.3 cases per medical scientist per day, representing a 31% improvement at 73% conversion. Numbers of unsatisfactory cases decreased substantially and the numbers of low and high-grade diagnoses were relatively constant.

CONCLUSIONS

The change to ThinPrep has improved productivity and decreased the number of unsatisfactory cases. There was no adverse effect on quality during the changeover.

Direct comparison of liquid-based and conventional cytology in a South African screening trial

Our study directly compares the performance of liquid-based (LBC) and conventional cytology for detecting high-grade cervical intraepithelial neoplasia and cancer (CIN 2+) in high-risk, previously unscreened women. As part of a larger randomized clinical trial assessing the efficacy and safety of a "screen and treat" program for cervical cancer prevention, 5,652 South African women, aged 35 to 65 years, were screened using either ThinPrep or conventional Papanicolaou cytology. The cytology method used (i.e., ThinPrep or conventional) was rotated on a 6-month basis for the duration of the study. Directly following collection of the cytology specimen, all women underwent colposcopy with endocervical curettage and biopsy of all colposcopic abnormalities. Assessment of cytology and histology results was blinded and results were compared using histology-confirmed CIN as the "gold standard." The accuracy of LBC and conventional cytology was statistically equivalent, although the sensitivity of conventional cytology was at least 5 percentage points higher at all cutoff levels. For example, at a cytology cutoff level of low-grade squamous intraepithelial lesion, the sensitivity of LBC was 60.3% for CIN2+ vs. 69.1% for conventional cytology and specificity was 94.1% and 94.5%, respectively. LBC specimens were significantly less likely to be "satisfactory-but-limited-by" (6.5% vs. 27.9%) but significantly more likely to be unsatisfactory (2.2% vs. 0.8%). Thus, in this high-risk population, the sensitivity of LBC is no greater than the sensitivity of conventional cytology. Because of the higher unit cost of LBC, low resource settings should carefully consider the potential benefits and drawbacks of LBC before adopting this new technology.