Utility of liquid-based cytology for cervical carcinoma screening: results of a population-based study conducted in a region of Costa Rica with a high incidence of cervical carcinoma

Clinical values of different specimen preparation methods for the diagnosis of lung cancer by EBUS-TBNA

BACKGROUND AND OBJECTIVE

EBUS-TBNA has emerged as an important minimally invasive procedure for the diagnosis and staging of lung cancer. Our objective was to evaluate the effect of different specimen preparation from aspirates on the diagnosis of lung cancer.

METHODS

181 consecutive patients with known or suspected lung cancer accompanied by hilar / mediastinal lymphadenopathy underwent EBUS-TBNA from January 2019 to December 2022. Specimens obtained by EBUS-TBNA were processed by three methods: Traditional smear cytology of aspirates (TSC), liquid-based cytology of aspirates (LBC) and histopathology of core biopsies.

RESULTS

EBUS-TBNA was performed in 181 patients on 213 lymph nodes, the total positive rate of the combination of three specimen preparation methods was 80.7%. The diagnostic positive rate of histopathology was 72.3%, TSC was 68.1%, and LBC was 65.3%, no significant differences was observed (p = 0.29); however, statistically significant difference was noted between the combination of three preparation methods and any single specimen preparation methods (p = 0.002). The diagnostic sensitivity of histopathology combined with TSC and histopathology combined with LBC were 96.5 and 94.8%, the specificity was 95.0% and 97.5%, the PPV was 98.8% and 99.4%, the NPV was 86.4% and 81.2%, the diagnostic accuracy was 96.2% and 95.3%, respectively; The sensitivity and accuracy of above methods were higher than that of single specimen preparation, but lower than that of combination of three preparation methods.

CONCLUSION

When EBUS-TBNA is used for the diagnosis and staging of lung cancer, histopathology combined with TSC can achieve enough diagnostic efficiency and better cost-effectiveness.

Accurate deep learning model using semi-supervised learning and Noisy Student for cervical cancer screening in low magnification images

Deep learning technology has been used in the medical field to produce devices for clinical practice. Deep learning methods in cytology offer the potential to enhance cancer screening while also providing quantitative, objective, and highly reproducible testing. However, constructing high-accuracy deep learning models necessitates a significant amount of manually labeled data, which takes time. To address this issue, we used the Noisy Student Training technique to create a binary classification deep learning model for cervical cytology screening, which reduces the quantity of labeled data necessary. We used 140 whole-slide images from liquid-based cytology specimens, 50 of which were low-grade squamous intraepithelial lesions, 50 were high-grade squamous intraepithelial lesions, and 40 were negative samples. We extracted 56,996 images from the slides and then used them to train and test the model. We trained the EfficientNet using 2,600 manually labeled images to generate additional pseudo labels for the unlabeled data and then self-trained it within a student-teacher framework. Based on the presence or absence of abnormal cells, the created model was used to classify the images as normal or abnormal. The Grad-CAM approach was used to visualize the image components that contributed to the classification. The model achieved an area under the curve of 0.908, accuracy of 0.873, and F1-score of 0.833 with our test data. We also explored the optimal confidence threshold score and optimal augmentation approaches for low-magnification images. Our model efficiently classified normal and abnormal images at low magnification with high reliability, making it a promising screening tool for cervical cytology.

Evaluation of a real-time optoelectronic method in the diagnostics of CIN over four years of observations

Cervical cancer is considered to be particularly amenable to prevention and highly treatable in its early stages. The real-time optoelectronic method of cervix examination seemed to be very promising in the detection of cervical squamous intraepithelial lesions and demonstrated relatively good efficacy. Although this method was introduced into clinics almost 10 years ago, it has not found its place in diagnostic schemes. At the moment, cytological smears and HPV detection with genotyping are still essential. TruScreen seems to be a slightly forgotten test. The aim of the study was to evaluate the efficacy and accuracy of TruScreen in detecting cervical pathology: CIN and cervical cancer confirmed with a histopathological diagnosis in comparison with other methods–cytology and colposcopy over four years of observations. The study was conducted on 130 women with abnormal Pap smear results. We can conclude that a real-time optoelectronic method like TruScreen can be useful as an effective initial cervical cancer screening in developing countries, possibly in combination with other methods. The combination of cytology and TruScreen examination may help clinicians to take decision about the next diagnostics steps (e.g. colposcopy) and contribute to better primary screening for cervical cancer.

An Observational Study of Deep Learning and Automated Evaluation of Cervical Images for Cancer Screening

BACKGROUND

Human papillomavirus vaccination and cervical screening are lacking in most lower resource settings, where approximately 80% of more than 500 000 cancer cases occur annually. Visual inspection of the cervix following acetic acid application is practical but not reproducible or accurate. The objective of this study was to develop a "deep learning"-based visual evaluation algorithm that automatically recognizes cervical precancer/cancer.

METHODS

A population-based longitudinal cohort of 9406 women ages 18-94 years in Guanacaste, Costa Rica was followed for 7 years (1993-2000), incorporating multiple cervical screening methods and histopathologic confirmation of precancers. Tumor registry linkage identified cancers up to 18 years. Archived, digitized cervical images from screening, taken with a fixed-focus camera ("cervicography"), were used for training/validation of the deep learning-based algorithm. The resultant image prediction score (0-1) could be categorized to balance sensitivity and specificity for detection of precancer/cancer. All statistical tests were two-sided.

RESULTS

Automated visual evaluation of enrollment cervigrams identified cumulative precancer/cancer cases with greater accuracy (area under the curve [AUC] = 0.91, 95% confidence interval [CI] = 0.89 to 0.93) than original cervigram interpretation (AUC = 0.69, 95% CI = 0.63 to 0.74; P < .001) or conventional cytology (AUC = 0.71, 95% CI = 0.65 to 0.77; P < .001). A single visual screening round restricted to women at the prime screening ages of 25-49 years could identify 127 (55.7%) of 228 precancers (cervical intraepithelial neoplasia 2/cervical intraepithelial neoplasia 3/adenocarcinoma in situ [AIS]) diagnosed cumulatively in the entire adult population (ages 18-94 years) while referring 11.0% for management.

CONCLUSIONS

The results support consideration of automated visual evaluation of cervical images from contemporary digital cameras. If achieved, this might permit dissemination of effective point-of-care cervical screening.

Values of different specimen preparation methods for the diagnosis of lung cancer by endobronchial ultrasound guided transbronchial needle aspiration

Background

Endobronchial ultrasound guided transbronchial needle aspiration (EBUS-TBNA) has been become an important procedure for the diagnosis and staging of lung cancer. Our research identified the effects of different pathological preparation on the diagnosis of lung cancer for specimens obtained by biopsy.

Methods

Patients were clinically considered if lung cancer was accompanied by mediastinal or hilar lymph node enlargement between March 2014 and November 2017. Specimens obtained by EBUS-TBNA were treated by three methods: traditional smear cytology, liquid-based cytology (LBC) and histopathology.

Results

Of a total of 154 puncture sites from 153 patients, the total positive rate of combination for the three pathological treatment types (histopathology, direct traditional smear, and LBC) was 77.3%. The diagnostic positive rate for histopathology was 68.6%, direct traditional smear was 65.6%, and LBC was 60.4%; there was no significant differences among the three single pathological treatment types (P = 0.29), but there was a statistically significant difference between the combination of three treatments and any single pathological treatment type (P = 0.01). The diagnostic sensitivities of histopathology combined with traditional smear and histopathology combined LBC were 94.4 and 92.8%, respectively, the specificities and PPVs were both 100%, and the diagnostic accuracies were 95.5 and 94.2%, respectively; the sensitivities, specificities and diagnostic accuracies above were all higher than those of single specimen treatment and lower than those of the three combined.

Conclusion

When EBUS-TBNA is used for the diagnosis and staging of lung cancer, the use of histopathological sections combined with direct cytological smear should be sufficient and is the most economical choice.

Detection of transformation zone cells in liquid-based cytology and its comparison with conventional smears

BACKGROUND

To compare the differences between liquid-based cytology (LBC) and conventional cytology in respect of the detection of transformation zone cells (TZC) by age group and to assess test performance by correlating results with cytological abnormalities.

METHODS

A retrospective study assessing the results of cervical-vaginal cytology smears collected at a private laboratory in São Paulo (Brazil) between January 2010 and December 2015.

RESULTS

A total of 1 030 482 cytology tests were performed; of these, 3811 (0.36%) unsatisfactory samples were excluded. Cytology sampling in the patients studied was performed using the conventional technique in 394 879 (38.5%) cases and the liquid-based techniques in 631 792 (61.5%) cases. The proportion of samples with TZC for interpretation was 73.2% (288 956 samples) in conventional cytology and 52.7% (333 115 samples) in LBC (P < .001). The presence of TZC rate declined in both groups with age, but was consistently lower for LBC (P < .001). The presence of endocervical and metaplastic cells was associated with higher high-grade intraepithelial lesion detection rates.

CONCLUSION

Low representation of the transformation zone was found in the samples collected using the LBC technique, particularly in the over 50 age group. Conventional cytology was associated with a higher rate of detection of high-grade lesions.

Current Status of and Perspectives on Cervical Cancer Screening in Korea

Since the introduction of the Papanicolaou (Pap) smear system in 1943, cervicovaginal cytology has been used as a standard screening test for cervical cancer. The dissemination of this test contributed to reductions of the incidence and mortality of cervical cancer worldwide. In Korea, regular health check-ups for industrial workers and their family members were introduced in 1988 and were performed as part of the National Cancer Screening Program in 1999. As a result, the incidence of cervical cancer in Korea has been steadily decreasing. However, about 800 cases of cervical cancer-related deaths are reported each year due to false-negative test results. Hence, new screening methods have been proposed. Liquid-based cytology (LBC) was introduced in 1996 to overcome the limitations of conventional Pap smears. Since then, other LBC methods have been developed and utilized, including the human papilloma virus test-a method with higher sensitivity that requires fewer screenings. In this study, we review current issues and future perspectives related to cervical cancer screening in Korea.

Current Status of and Perspectives on Cervical Cancer Screening in Korea

Since the introduction of the Papanicolaou (Pap) smear system in 1943, cervicovaginal cytology has been used as a standard screening test for cervical cancer. The dissemination of this test contributed to reductions of the incidence and mortality of cervical cancer worldwide. In Korea, regular health check-ups for industrial workers and their family members were introduced in 1988 and were performed as part of the National Cancer Screening Program in 1999. As a result, the incidence of cervical cancer in Korea has been steadily decreasing. However, about 800 cases of cervical cancer-related deaths are reported each year due to false-negative test results. Hence, new screening methods have been proposed. Liquid-based cytology (LBC) was introduced in 1996 to overcome the limitations of conventional Pap smears. Since then, other LBC methods have been developed and utilized, including the human papilloma virus test-a method with higher sensitivity that requires fewer screenings. In this study, we review current issues and future perspectives related to cervical cancer screening in Korea.

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.

Diagnostic Test Accuracy Review of Cytology for Squamous Intraepithelial Lesion and Squamous Cell Carcinoma of Uterine Cervix

BACKGROUND

Even though cervico-vaginal smears have been used as a primary screening test for cervical carcinoma, the diagnostic accuracy has been controversial. The present study aimed to evaluate the diagnostic accuracy of cytology for squamous intraepithelial lesion (SIL) and squamous cell carcinoma (SqCC) of the uterine cervix through a diagnostic test accuracy (DTA) review.

METHODS

A DTA review was performed using 38 eligible studies that showed concordance between cytology and histology. In the DTA review, sensitivity, specificity, diagnostic odds ratio (OR), and the area under the curve (AUC) on the summary receiver operating characteristic (SROC) curve were calculated.

RESULTS

In the comparison between abnormal cytology and histology, the pooled sensitivity and specificity were 93.9% (95% confidence interval [CI], 93.7%-94.1%) and 77.6% (95% CI, 77.4-77.8%), respectively. The diagnostic OR and AUC on the SROC curve were 8.90 (95% CI, 5.57-14.23) and 0.8148, respectively. High-grade squamous intraepithelial lesion (HSIL) cytology had a higher sensitivity (97.6%; 95% CI, 94.7%-97.8%) for predicting HSIL or worse histology. In the comparison between SqCC identified on cytology and on histological analysis, the pooled sensitivity and specificity, diagnostic OR, and AUC were 92.7% (95% CI, 87.3%-96.3%), 87.5% (95% CI, 87.2%-87.8%), 865.81 (95% CI, 68.61-10,925.12), and 0.9855, respectively. Geographic locations with well-organized screening programs had higher sensitivity than areas with insufficient screening programs.

CONCLUSION

These results indicate that cytology had a higher sensitivity and specificity for detecting SIL and SqCC of the uterine cervix during primary screening.

Conventional Pap Smear and Liquid-based Cervical Cytology Smear: Comparison from the Same Patient

Background

The results of blind reading of smears obtained with liquid-based cytology in patients previously screened by conventional cytology were compared.

Material and methods

Cases selected for the study were a consecutive series of 99 subjects undergoing colposcopy within the screening program of the Florence District. The Pap test samples were processed utilizing the Thin Prep 2000 (Cytyc Corporation, Boxborough, MA). The liquid-base cytology smears were randomly admixed and read by seven expert cytologists with more than 15 years of experience in Pap smear reading. For each case, a consensus diagnosis was created and considered as the definitive diagnosis. Cytologic reports in conventional and liquid-based cytology smears were compared by the κ statistic to evaluate diagnostic agreement.

Results

The study showed that the conventional and liquid-based cytology provide comparable cytologic reports and that the latter is not less sensitive than the former in detecting CIN2+ lesions of the cervix.

Discussion

Such evidence suggests the feasibility of randomized studies comparing the two methods, which are needed before adopting liquid-based cytology as the current method when screening for cervical cancer.

Increased proportions of HIV-infected women met cervical cancer screening guideline in 2016

Background

HIV-infected women are five times more likely to develop invasive cervical cancer. Routine screening can detect early signs of cancer and provide an opportunity for treatment. However, suboptimal screening rates are reported in this population. This retrospective study examined the rates of cervical cancer screening in HIV-positive women, conducted according to the current guidelines, from 2014 to 2016 in an inner-city clinic.

Materials and methods

We implemented focused scheduling for eligible women by a designated medical assistant. Testing was conducted using Thin Prep™ and Cervista HPV HR™. Chi-square tests and logistic regression models were used to assess predictors of cervical cancer screening in 2016.

Results

A total of 360 adult HIV-infected women were active in medical care, as of December 31, 2016. Most were African American (77%) and aged 51-60 years (38%). In 2016, 75% of women met the guidelines for cervical cancer screening, compared to 48% in 2014. There was a significant association between receipt of cervical cancer screening in the prior 3 years and screening in 2016. In an adjusted model, those with a prior screening were 6.88 times (95% CI, 3.47-13.67) more likely to be screened in 2016, compared to those who were never previously screened.

Conclusion

Focused scheduling and implementation of the updated cervical cancer screening guideline extending the period of rescreening, after 3 yearly negative results or negative Papanicolaou/human papilloma virus testing, resulted in an increased proportion of women meeting the current guideline.

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.

Cervical cytology as a diagnostic tool for female genital schistosomiasis: Correlation to cervical atypia and Schistosoma polymerase chain reaction

Background:

Female genital schistosomiasis (FGS) is a tissue reaction to lodged ova of Schistosoma haematobium in the genital mucosa. Lesions can make the mucosa friable and prone to bleeding and discharge. Women with FGS may have an increased risk of HIV acquisition, and FGS may act as a cofactor in the development of cervical cancer.

Objectives:

To explore cytology as a method for diagnosing FGS and to discuss the diagnostic challenges in low-resource rural areas. The correlation between FGS and squamous cell atypia (SCA) is also explored and discussed. Cytology results are compared to Schistosoma polymerase chain reaction (PCR) in vaginal lavage and urine and in urine microscopy.

Materials and Methods:

In a clinical study, 394 women aged between 16 and 23 years from rural high schools in KwaZulu-Natal, South Africa, underwent structured interviews and the following laboratory tests: Cytology Papanicolaou (Pap) smears for S. haematobium ova and cervical SCA, real-time PCR for Schistosoma-specific DNA in vaginal lavage and urine samples, and urine microscopy for the presence of S. haematobium ova.

Results:

In Pap smears, S. haematobium ova were detected in 8/394 (2.0%). SCA was found in 107/394 (27.1%), seven of these had high-grade squamous intraepithelial lesion (HSIL). Schistosoma specific DNA was detected in 38/394 (9.6%) of vaginal lavages and in 91/394 (23.0%) of urines. Ova were found microscopically in 78/394 (19.7%) of urines.

Conclusion:

Schistosoma PCR on lavage was a better way to diagnose FGS compared to cytology. There was a significant association between S. haematobium ova in Pap smears and the other diagnostic methods. In low-resource Schistosoma-endemic areas, it is important that cytology screeners are aware of diagnostic challenges in the identification of schistosomiasis in addition to the cytological diagnosis of SCA. Importantly, in this study, three of eight urines were negative but showed Schistosoma ova in their Pap smear, and one of them was also negative for Schistosoma DNA in urine. In this study, SCA was not significantly associated with schistosomiasis. HSIL detected in this young population might need future consideration.

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.

Implementation status of cervical screening in Europe

Following the recommendation of the Council of the European Union, almost all governments made a policy statement on the introduction of cytology-based cervical screening for the health care system. However, the status of implementation is uneven. In the majority of the developed countries an organised model of screening recommended by the relevant international professional organisations are in use, while occasional screening is applied in some other countries. Screening strategies (i.e. age range, screening intervals), coverage of the target population, and compliance rates vary significantly. The screening activities are in a planning phase is some less developed Central-Eastern and South European countries. In Hungary, the transition from the traditional “gynaecological cancer screening” into the recommended organised cervical screening is in progress; the active involvement of the district health visitors in the cervical screening would provide further improvement. Orv. Hetil., 2014, 155(50), 1975–1988.

Internal quality control for cervical cytopathology: comparison of potential false-negatives detected at rapid prescreening and at 100% rapid review

OBJECTIVE

To evaluate the performance of rapid prescreening (RPS) and 100% rapid review (RR-100%) as internal quality control (IQC) methods assessed by outcome at colposcopy, histopathology and repeat cytopathology for cases with false-negative results on cervical cytopathology at routine screening (RS).

STUDY DESIGN

Out of 12,208 cytology smears analyzed, 900 were abnormal. Of these, 656 were identified at RS, and 244 were false-negative, with 90.2% identified at RPS and 57.4% at RR-100%. Of the 900 abnormal cases, 436 were submitted for additional testing.

RESULTS

Of the 244 women with cytopathological abnormalities identified only by the IQC methods, 114 had supplementary examinations: 35 were submitted for colposcopy, 22 for biopsy and 99 for repeat cytopathology. The sensitivity of RPS for the detection of abnormalities identified on colposcopy, histopathology and repeat cytopathology was 87.5% (95% CI 67.6-97.3), 82.4% (95% CI 56.6-96.2) and 95.7% (95% CI 85.2-99.5), respectively. The sensitivity of RR-100% was 54.2% (95% CI 32.8-74.4), 52.9% (95% CI 27.8-77.0) and 47.8% (95% CI 32.9-63.1), respectively. RPS was more sensitive than RR-100% when compared to the findings on colposcopy (p = 0.011) and repeat cytopathology (p = 0.000). When compared to colposcopy, histopathology and repeat cytopathology, the sensitivity of RS was 83.2% (95% CI 76.1-88.9), 85.7% (95% CI 78.1-91.5) and 73.3% (95% CI 66.0-79.7), respectively.

CONCLUSION

RPS performed better than RR-100% when compared to the results of colposcopy and repeat cytopathology.

Diagnostic efficacy of cell block immunohistochemistry, smear cytology, and liquid-based cytology in endoscopic ultrasound-guided fine-needle aspiration of pancreatic lesions: a single-institution experience

Background

The diagnostic efficiency of endoscopic ultrasound-guided fine-needle aspiration (EUS-FNA) cytology varies widely depending on the treatment method of the specimens. The present study aimed to evaluate the diagnostic efficacy of cell block (CB) immunohistochemistry, smear cytology (SC), and liquid-based cytology (LBC) in patients with pancreatic lesions without consulting an on-site cytopathologist.

Methods

This study prospectively enrolled 72 patients with pancreatic lesions. The EUS-FNA specimens were examined by SC, LBC, and CB immunohistochemistry. The diagnostic efficacy of the 3 methods was then compared. Patients’ final diagnosis was confirmed by surgical resection specimens, diagnostic imaging, and clinical follow-up.

Results

Our results included 60 malignant and 12 benign pancreatic lesions. The diagnostic sensitivity (90%), negative predictive value (66.7%), and accuracy (91.7%) of CB immunohistochemistry were significantly higher than those of SC (70.0%, 30.0%, and 75.0%, respectively) and LBC (73.3%, 31.6%, and 77.8%, respectively) (all P<0.05). The combination of CB and SC, or CB and LBC, did not significantly increase the efficacy compared to CB immunohistochemistry alone.

Conclusion

Our findings suggest that in the absence of an on-site cytopathologist, CB immunohistochemistry on EUS-FNA specimens offers a higher diagnostic efficacy in patients with pancreatic lesions than does SC and LBC.

Test execution variation in peritoneal lavage cytology could be related to poor diagnostic accuracy and stage migration in patients with gastric cancer

PURPOSE

Peritoneal lavage cytology is part of the routine staging workup for patients with advanced gastric cancer. However, no quality assurance study has been conducted to show variations or biases in peritoneal lavage cytology results. The aim of this study was to demonstrate a test execution variation in peritoneal lavage cytology between investigating surgeons.

MATERIALS AND METHODS

A prospective cohort study was designed for determination of the positive rate of peritoneal lavage cytology using a liquid-based preparation method in patients with potentially curable advanced gastric cancer (cT2~4/N0~2/M0). One hundred thirty patients were enrolled and underwent laparotomy, peritoneal lavage cytology, and standard gastrectomy, which were performed by 3 investigating surgeons. Data were analyzed using the chi-square test and a logistic regression model.

RESULTS

The overall positive peritoneal cytology rate was 10.0%. Subgroup positive rates were 5.3% in pT1 cancer, 2.0% in pT2/3 cancer, 11.1% in pT4a cancer, and 71.4% in pT4b cancer. In univariate analysis, positive peritoneal cytology showed significant correlation with pT stage, lymphatic invasion, vascular invasion, ascites, and the investigating surgeon. We found the positive rate to be 2.1% for surgeon A, 10.2% for surgeon B, and 20.6% for surgeon C (P=0.024). Multivariate analysis identified pT stage, ascites, and the investigating surgeon to be significant risk factors for positive peritoneal cytology.

CONCLUSIONS

The peritoneal lavage cytology results were significantly affected by the investigating surgeon, providing strong evidence of test execution variation that could be related to poor diagnostic accuracy and stage migration in patients with advanced gastric cancer.

Evaluation of a low-cost liquid-based Pap test in rural El Salvador: a split-sample study

OBJECTIVE

We sought to test the diagnostic efficacy of a low-cost, liquid-based cervical cytology that could be implemented in low-resource settings.

MATERIALS AND METHODS

A prospective, split-sample Pap study was performed in 595 women attending a cervical cancer screening clinic in rural El Salvador. Collected cervical samples were used to make a conventional Pap (cell sample directly to glass slide), whereas residual material was used to make the liquid-based sample using the ClearPrep method. Selected samples were tested from the residual sample of the liquid-based collection for the presence of high-risk Human papillomaviruses.

RESULTS

Of 595 patients, 570 were interpreted with the same diagnosis between the 2 methods (95.8% agreement). There were comparable numbers of unsatisfactory cases; however, ClearPrep significantly increased detection of low-grade squamous intraepithelial lesions and decreased the diagnoses of atypical squamous cells of undetermined significance. ClearPrep identified an equivalent number of high-grade squamous intraepithelial lesion cases as the conventional Pap. High-risk human papillomavirus was identified in all cases of high-grade squamous intraepithelial lesion, adenocarcinoma in situ, and cancer as well as in 78% of low-grade squamous intraepithelial lesions out of the residual fluid of the ClearPrep vials.

CONCLUSIONS

The low-cost ClearPrep Pap test demonstrated equivalent detection of squamous intraepithelial lesions when compared with the conventional Pap smear and demonstrated the potential for ancillary molecular testing. The test seems a viable option for implementation in low-resource settings.

American cancer society guideline for the early detection of cervical neoplasia and cancer

An update to the American Cancer Society (ACS) guideline regarding screening for the early detection of cervical neoplasia and cancer, based on recommendations from a formal review and recent workshop, is presented. The new screening recommendations address when to begin screening, when screening may be discontinued, whether to screen women who have had a hysterectomy, appropriate screening intervals, and new screening technologies, including liquid-based cytology and HPV DNA testing.

Chapter 6: assessing applicability of medical test studies in systematic reviews

Use of medical tests should be guided by research evidence about the accuracy and utility of those tests in clinical care settings. Systematic reviews of the literature about medical tests must address applicability to real-world decision-making. Challenges for reviews include: (1) lack of clarity in key questions about the intended applicability of the review, (2) numerous studies in many populations and settings, (3) publications that provide too little information to assess applicability, (4) secular trends in prevalence and the spectrum of the condition for which the test is done, and (5) changes in the technology of the test itself. We describe principles for crafting reviews that meet these challenges and capture the key elements from the literature necessary to understand applicability.

Application of TruScreen in detecting ASCUS patients

OBJECTIVE

To explore the application of cervical cancer screening system, TruScreen in detecting atypical squamous cell of undetermined significance (ASCUS) patients.

METHODS

A total of 42 cases were selected, who were diagnosed as ASCUS by thinprep cytologic test (TCT). Area from site 15 to 20, site 21 to 32 were detected by TruScreen. And the result was compared with those of cases which had positive pathological result of cervical biopsy.

RESULTS

There were 16 cases with abnormal pathological result in ASCUS cases, including 6 cases with cervical intraepithelial neoplasia (CIN) I, 6 cases with CIN II, 3 cases with CIN III and 1 case with infiltrating carcinoma. The consistency between TCT and pathological test was 38.10% (16/42). The positive rate of TruScreen at site 15-20 was 61.91% (26/42). There was significant difference in consistency with pathological test between TCT and TruScreen (x(2)=4.762, P=0.029). The positive rate of TruScreen at site 21-32 was 66.67% (28/42)(Kappa=0.181, P=0.016). There was significant difference in consistency with pathological test between TCT and TruScreen (x(2)=9.4919, P=0.002). And no case was missed when site 21-32 of patients with CINII and above were detected by TruScreen.

CONCLUSIONS

TruScreen is effective in detecting ASCUS patients.

Human Papillomavirus and Pap Smear

High-risk human papillomavirus (HPV) infection and viral persistence is a major risk factor in the development of squamous intraepithelial lesions and invasive carcinoma of the cervix. In the United States, deaths due to squamous cell carcinoma of the cervix have fallen by 75% since the 1960s because of Papanicolaou (Pap) smear screening. However, the traditional Pap had a sensitivity of about 70% for detecting clinically significant precancerous lesions and cancer because of sampling and interpretive errors. The introduction of 2 liquid-based Pap smear collection systems in the 1990s, the use of HPV testing as a triage and co-testing with Pap smear, and the introduction of 2 automated screening devices have had a significant impact on improving the detection of such precancerous lesions. This review provides an analysis of the changes in Pap smear collection, improvements in screening, the evolutionary changes of high-risk HPV testing, reporting terminology of Pap smears, and clinical management guidelines. The future impact of 2 prophylactic HPV vaccines on the incidence of cervical carcinoma is also discussed. This article also discusses alternatives such as primary screening for high-risk HPV testing with visual inspection for cervical cancer detection used in resource-poor settings with a high incidence of cervical cancer.

Comparison of the performance of anal cytology and cervical cytology as screening tests

Cervical cytology screening has a long history and has successfully reduced the impact of cervical cancer in many countries. Anal cytology is a relative newcomer and anal screening is currently offered in only a few centres around the world. Many questions need to be answered before anal screening is more widely adopted. While there are many similarities between cervical and anal squamous cell carcinoma, there are also important differences: differences in the prevalence of disease, in the ‘at-risk’ target populations and possibly in the robustness of the reference standard of biopsy. The performance of cytology as a screening test in the literature varies widely but it is essential to understand that some of this variability is due to differences in the definitions of key parameters in the various studies. For cervical screening, estimates of sensitivity have ranged from 19% to 94% and specificity from 94% to 98%. For anal screening, data are fewer and more limited. Estimates of the sensitivity of anal cytology in men who have sex with men and HIV-positive populations have ranged from 55% to 87% and specificity from 37% to 76%. Ultimately, rather than comparing anal with cervical cytology, it may be more helpful to assess the value of anal cytology independently through well designed trials.

Longitudinal analysis of carcinogenic human papillomavirus infection and associated cytologic abnormalities in the Guanacaste natural history study: looking ahead to cotesting

BACKGROUND

Few studies have addressed the timing of cervical cytologic abnormalities and human papillomavirus (HPV) positivity during the course of an infection. It remains largely unknown how infections detected by HPV and cytology wax and wane relative to each other. The aim of this analysis was to assess the longitudinal relationship of abnormal cytology and HPV positivity in a 7-year prospective study of 2500 women in Guanacaste, Costa Rica.

METHODS

At each semiannual or annual visit, cervical specimens were screened using liquid-based cytology and tested for >40 HPV types with use of MY09/MY11 L1 degenerate primer polymerase chain reaction-based methods. On the basis of previous work, we separated prevalent and newly detected infections in younger and older women.

RESULTS

Among newly detected HPV- and/or cytology-positive events, HPV and cytology appeared together ∼60% of the time; when discordant, HPV tended to appear before cytology in younger and older women. Combining newly and prevalently detected events, HPV and cytology disappeared at the same time >70% of the time. When discordant, HPV tended to disappear after cytology in younger and older women.

CONCLUSIONS

Detection of HPV DNA and associated cytological abnormalities tend to come and leave together; however, when discordant, detection of HPV DNA tends to precede and/or last longer than associated cytologic abnormalities.

Cost-effectiveness analysis for Pap smear screening and human papillomavirus DNA testing and vaccination

INTRODUCTION

As the effectiveness of cytology-based screening programme for cervical cancer in mortality reduction has reached a plateau, various preventive strategies have been considered, including intensive Pap smear screening and the supplemental use of human papillomavirus (HPV) DNA test or HPV vaccination. Cost and effectiveness of these various preventive strategies are therefore of great concern for health policy makers.

OBJECTIVE

We intended to assess whether the combination of HPV DNA testing or HPV vaccination with Pap smear screening programme or the sole annual Pap smear screening is more effective and cost-effective in prevention of cervical cancer than the existing triennial Pap smear screening programme.

METHODS

A Markov decision model was constructed to compare total costs and effectiveness between different preventive strategies (including annual Pap smear, HPV DNA testing or HPV vaccination together with Pap smear screening programme) as opposed to the triennial Pap smear screening alone (the comparator). Probabilistic cost-effectiveness (C-E) analysis was adopted to plot a series of simulated incremental C-E ratios scattered over C-E plane and also to yield the acceptability curve for different comparisons of strategies. The threshold of vaccine cost and the influence of attendance rate were also investigated.

RESULTS

Compared with triennial Pap smear screening programme, most of preventive strategies cost more but gain additional life years (quadrant I of C-E plane) except HPV DNA testing with Pap smear every 5 years dominated by triennial Pap smear screening programme. The most cost-effective strategy was annual Pap smear (incremental C-E ratio = $31 698), followed by HPV DNA testing with Pap smear every 3 years ($36 627), and vaccination programme with triennial Pap smear screening ($44 688) with the corresponding cost-effective probabilities by the acceptability curve being 65.52%, 52.08% and 35.84% given the threshold of $40 000 of willingness to pay. Vaccination combined with triennial Pap smear would be as cost-effective as annual Pap smear provided the cost of vaccination was lowered to $250 per full course of injection.

CONCLUSIONS

Among various preventive strategies annual Pap smear screening programme is still the most cost-effective and additional HPV DNA testing is a cost-effective choice under a reasonable threshold of willingness to pay. Vaccination programme in combination with triennial screening would be cost-effective if vaccine cost can be greatly reduced in a large economic scale.

Histological correlation of glandular abnormalities in cervical liquid-based cytology

Conventional Papanicolaou smear method is still commonly used for cervical cancer screening in Japan, despite the liquid-based cytology (LBC) that has become a global tendency in the world recently. One of the obstacles in the way of popularization of this method seems to be the confusion as to diagnosis upon cervical glandular lesions. We performed comparison study between LBC and conventional Papanicolaou smear about cytological diagnosis using split-sample method in 4522 patients. In 13 cases analyses, which were reported with either AGC or adenocarcinoma by either method, LBC tends to be milder than that by conventional smear, however, the credibility of LBC is considered to be near to that of conventional smear with regard to screening for glandular abnormalities. These results indicate that cervical cancer screening should shift to LBC under the enough experience and appropriate dealing with the cytological diagnosis.

Long-term risk of recurrent cervical human papillomavirus infection and precancer and cancer following excisional treatment

Risk of recurrent CIN2+ (including cervical intraepithelial neoplasia grade 2 [CIN2], CIN3, carcinoma and in situ, adenocarcinoma in situ or cancer) remains elevated for years following treatment. The role of long-term post-treatment human papillomavirus (HPV) presence on subsequent risk of CIN2+ was evaluated in the 10,049-women Guanacaste cohort. Six hundred eighty-one women were referred to colposcopy because of high-grade cytology, positive cervicography and/or suspicion of cancer based on visual assessment; 486 were judged to require treatment. After excluding women with <12 months of follow-up (N = 88), prior cancer or hysterectomy (N = 37) or other reasons (N = 14), 347 were included in the analysis. Infections were categorized as persistent if present at both pre- and post-treatment visits and new if detected only post-treatment. Median time between the treatment and post-treatment visits was 6.7 years (interquartile range 3.8-7.8). At the post-treatment visit, 8 (2.4%), 2 (0.6%) and 8 (2.4%) of the 347 treated women had persistent HPV16, HPV18 or other carcinogenic HPV, respectively. Two (0.8%), 3 (1.0%) and 13 (4.0%) had new HPV16, HPV18 and other carcinogenic HPV, respectively. Six CIN2+ cases were identified at the post-treatment visit, all with persistent infections (three HPV16, one HPV18 and two other carcinogenic HPV). No recurrent disease was observed among women with new HPV infections during the follow-up period. Thus, persistence of HPV infection a median of six years after treatment was uncommon but, when present, posed a substantial risk of subsequent CIN2+. Serial follow-up data from other studies would further strengthen these conclusions.

[Epidemiology, characterization of genotypes of human papillomavirus in a population of women in Ouagadougou]

OBJECTIVES

This work was carried out in order to determine the prevalence of different HPV genotypes in a population of women attending gynecological consultation.

MATERIAL AND METHODS

From May to June 2010, cervical samples were obtained from 300 women attending gynecological consultation in two health centers in Ouagadougou. The strains of HPV genotyping was done using the technique of polymerase chain reaction (PCR) followed by reverse hybridization on nitrocellulose strips.

RESULTS

Among the 73 women(24.3%) infected with HPV, only 27.4% (20/73) of them were infected with a HPV low risk (BR), the 72.6% (53/73). Other women were infected with at least one high risk HPV (HR). By combining the HPV genotypes found without taking into account the number of infected women, we found a total of 84 HPV among whom we have high-risk HPV : HPV-50'S(26/84 or 31.0%), HPV-18 (12/84 or 14.3%), HPV-16 (9/84 or 10.7%), HPV-30'S (5/84 or 5.9%), HPV-HR (5/84 or 5.9%) and HPV-45 (3/84 or 3.6%) and low-risk HPV: HPV-6 (15/84 or 17.9%) and HPV-BR (9/84 or 10.7%). We have found no HPV-11.

DISCUSSION AND CONCLUSION

The prevalence of HPV found in our series is comparable to that found in the world. To complete this study, it would be necessary to investigate the prevalence of HPV found in cervical lesions in Burkina Faso.

Human papillomavirus testing in the prevention of cervical cancer

Strong evidence now supports the adoption of cervical cancer prevention strategies that explicitly focus on persistent infection with the causal agent, human papillomavirus (HPV). To inform an evidence-based transition to a new public health approach for cervical cancer screening, we summarize the natural history and cervical carcinogenicity of HPV and discuss the promise and uncertainties of currently available screening methods. New HPV infections acquired at any age are virtually always benign, but persistent infections with one of approximately 12 carcinogenic HPV types explain virtually all cases of cervical cancer. In the absence of an overtly persistent HPV infection, the risk of cervical cancer is extremely low. Thus, HPV test results predict the risk of cervical cancer and its precursors (cervical intraepithelial neoplasia grade 3) better and longer than cytological or colposcopic abnormalities, which are signs of HPV infection. The logical and inevitable move to HPV-based cervical cancer prevention strategies will require longer screening intervals that will disrupt current gynecologic and cytology laboratory practices built on frequent screening. A major challenge will be implementing programs that do not overtreat HPV-positive women who do not have obvious long-term persistence of HPV or treatable lesions at the time of initial evaluation. The greatest potential for reduction in cervical cancer rates from HPV screening is in low-resource regions that can implement infrequent rounds of low-cost HPV testing and treatment.

Comparison of Papanicolaou test with visual detection tests in screening for cervical cancer and developing the optimal strategy for low resource settings

OBJECTIVES

To compare the sensitivity, specificity, positive and negative predictive values, and accuracy of Papanicolaou test with visual inspection with acetic acid (VIA)/VIA using magnification devices (VIAM) and develop the best strategy for screening in low resource settings.

MATERIALS AND METHODS

This is a prospective cross-sectional study on 408 symptomatic multiparous women in the reproductive age group, sequentially using the Papanicolaou test, the VIA, and the VIAM for screening. Women with a positive screening test underwent guided biopsy and endocervical curettage. The site of biopsy was recorded. Histopathological findings were taken as the "gold" standard in comparing the methods.

RESULTS

The mean (SD) age was 32.3 (6.8) years (range, 15-49 years), whereas the mean (SD) parity was 2.9 (1.2) (range, 1-9). Abnormal cytological findings were detected in 2.9% patients, whereas the remaining smears were negative for any intraepithelial lesion or malignancy. A total of 113 cases were screened positive by one/all methods. The sensitivity, specificity, positive predictive value, negative predictive value, and accuracy of the Papanicolaou test, the VIA, and the VIAM were 24, 98, 42, 96, and 94%; 95, 78, 19, 99, and 79%; and 95, 78, 19, 99, and 79%, respectively, for high-grade lesions.

CONCLUSIONS

The Papanicolaou test had low sensitivity but high specificity, whereas visual detection methods had a high sensitivity in addition to being cheaper. Alternative methods of screening such as VIA/VIAM can be a valuable alternative to the Papanicolaou test for cervical cancer screening in low resource settings. Visual inspection using magnification devices may be of benefit over VIA in doubtful cases.

Liqui-Prep® versus conventional Papanicolaou smear to detect cervical cells abnormality by split-sample technique: a randomized double-blind controlled trial

To assess the diagnostic performances of LiquiPrep® (LP) to detect cervical cellular abnormality in comparison to Papanicolaou (Pap) smear in 194 women with abnormal cervical cytology who were scheduled for colposcopy at the institution between January 2008 and November 2008. The women were randomized to undergo a repeated cervical cytologic evaluation by Pap smear followed by LP, or the two methods in alternating order. The pathologist was blinded to previous cytologic diagnosis and the pair of slides assigned for each woman. Cytologic results from each method were compared to subsequent histopathology. Mean screening time for each LP and Pap slides were 4.3 ± 1.2 minutes and 5.4 ± 1.1 minutes, respectively (P < 0.001). From 194 cases, ASC or AGC were diagnosed in 72 cases (37.1%) from LP and 68 cases (35.1%) from Pap smear. After excluding the ASC/AGC group, the overall cytologic diagnostic agreement between the two tests were 69 of 87 cases (73.6%) while the agreements with histologic diagnoses were 39/87 cases from LP (44.8%) and 41 (47.1%) from Pap smear (P = 0.824). The accuracy of LP was not significantly different from Pap test, 43.4% (95% confidence interval [CI]: 34.8-52.1%) compared to 44.4% (95% CI: 35.7-53.1%). LP did not have superior performance over Pap test to detect high-grade lesions (≥ cervical intraepithelial neoplasia II) using ASC/AGC as the threshold with the sensitivity of 70.5% (95% CI: 64.0-76.9%) versus 77.3% (95% CI: 71.4-83.2%), respectively.

Sensibilidade e especificidade da citologia anal com escova no diagnóstico das lesões clínicas provocadas pelo papilomavírus humano, comparando uma com duas coletas

OBJETIVO: comparar os resultados da coleta única com duas amostras para avaliar se haverá melhora da sensibilidade e especificidade do exame. MÉTODO: Foram 112 doentes masculinos HIV-positivo com doença anal pregressa ou atual pelo Papilomavírus humano (HPV). As lesões HPV induzidas foram observadas em 58 deles. Colhemos material do canal anal utilizando duas escovas (cytobrush) Comparamos estatisticamente os resultados da primeira amostra com a soma das duas coletas. RESULTADOS: dos 58 doentes com lesões clínicas, a primeira amostra confirmou a doença em 40 (69%) e a soma das duas coletas revelou lesões em 51 (88%). Os resultados mostraram sensibilidade de 69% com a primeira coleta e 88% quando somadas as duas amostras. Essa diferença foi confirmada estatisticamente. A especificidade foi menor para as duas amostras, porém sem diferença estatística. CONCLUSÃO: Concluímos que a sensibilidade foi maior e a especificidade foi semelhante quando os resultados foram obtidos com a somação das duas amostras da citologia anal.

ASC/SIL Ratio for Cytotechnologists: A surrogate marker of screening sensitivity

The atypical squamous cell/squamous intraepithelial lesion (ASC/SIL) ratio has been used as a surrogate quality control tool for specificity and uncertainty for cytopathologists. Whether this ratio is useful for cytotechnologists is not known. During an 8-month period, the sensitivity of screening for 11 cytotechnologists was determined using rapid prescreening. The ASC/SIL ratio for each cytotechnologist was correlated with the screening accuracy for each. Screening sensitivity varied from 50.5% to 97.7%, and the ASC/SIL ratio varied from 0.87 to 4.49. The mean screening sensitivity for cytotechnologists with ASC/SIL ratios less than 1.5 was significantly less than that of cytotechnologists whose ASC/SIL ratio was more than 3.0 (67% vs 95%; P = .021). In the absence of more accurate quality control data, an ASC/SIL ratio less than 1.5 for a cytotechnologist may be a surrogate marker for inadequate screening sensitivity.

Cervical cancer screening in the early post vaccine era

The Pap test is the foundation of cervical cancer screening in North America and most industrialized countries. It has been widely used in the United States since the 1950s. But are our current screening guidelines still justified? In this article, the author reviews the current recommendations for cervical cancer screening by the American Cancer Society (ACS) and the American College of Obstetricians and Gynecologists (ACOG) and the evidence supporting them, reviews the relative efficacy of liquid-based cytology versus the conventional Pap smear, and discusses the role of HPV DNA testing in primary screening.

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.

New approaches to cervical cancer screening in Latin America and the Caribbean

Cervical cancer remains an important public health problem in the Latin America and Caribbean region (LAC), with an expected significant increase in disease burden in the next decades as a result of population ageing. Prophylactic human papillomavirus (HPV) vaccine is currently unaffordable in LAC countries. However, even if vaccination was implemented, an additional two decades will be required to observe its impact on HPV related disease and cancer. With some exceptions, cytology-based screening programs have been largely ineffective to control the problem in the region, and there is a need for new approaches to the organization of screening and for use of newly developed techniques. Several research groups in LAC have conducted research on new screening methods, some of which are summarized in this paper. A recommendation to reorganize screening programs is presented considering visual inspection for very low resource areas, improvement of cytology where it is operating successfully and HPV DNA testing followed by visual inspection with acetic acid (VIA) or cytology as soon as this method becomes technically and economically sustainable. This could be facilitated by the incorporation of new, low-cost HPV DNA testing methods and the use of self-collected vaginal specimens for selected groups of the population. An important requisite for screening based on HPV testing will be the quality assurance of the laboratory and the technique by validation and certification measures.

Preventing cervical cancer: the Pap test and the HPV vaccine

Women look to their internists and other primary care physicians to provide preventive health care. Periodic Pap tests are as much a part of a woman's ongoing health care as periodic lipid assessments, mammograms, screening for colon cancer, or any of the other recommended screening assessments. This article provides primary care physicians with the information needed to perform Pap tests at the appropriate intervals, or if not set up to do Pap tests themselves, to make the appropriate referrals. Also provided is the necessary information to counsel women with abnormal Pap tests who may need colposcopy or other follow-up evaluation. Finally, the role of the HPV vaccine in the prevention of cervical cancer is summarized.

Longitudinal clinical evaluation of a novel antibody cocktail for detection of high-grade squamous intraepithelial lesions on cervical cytology specimens

CONTEXT

Although cervical cancer screening by cytology is successful, the test continues to show relatively poor operating characteristics. Cell cycle markers may enhance detection of high-grade squamous intraepithelial lesions.

OBJECTIVE

To determine the clinical usefulness of ProExC, an immunocytochemical assay for cell cycle components, performed on routine cervical cytology samples.

DESIGN

Cervical cytology samples were collected using the SurePath method. Residual cells remaining after preparation of the Papanicolaou-stained slide were used to make a second slide for ProExC staining using an indirect polymer-based immunoperoxidase method. Only adequately cellular slides were evaluated for the presence of nuclear staining within cytologically abnormal epithelial cells. Results were correlated with clinical follow-up.

RESULTS

Six hundred twenty-four samples were satisfactorily cellular and stained. Correlation with clinical follow-up for subsequent cervical intraepithelial neoplasia 2+ on biopsy/high-grade squamous intraepithelial lesion on cytology (CIN 2+/HSIL) showed that 434 results were true negative, 78 true positive, 18 false-negative, and 94 false-positive, resulting in a sensitivity/specificity of 81%/82%. When ProExC results were combined with any level of cytologic atypia, sensitivity for CIN 2+/HSIL was 92% and specificity was 84%.

CONCLUSIONS

ProExC shows promise as an aid in enhancing the sensitivity and specificity of cervical cytology for subsequent CIN 2+/HSIL and may be useful in identifying those cervical lesions most apt to progress.

Indications and efficacy of the human papillomavirus vaccine

In the United States, there are 11,150 cases and 3670 deaths projected due to invasive cervical cancer for 2007. Approximately 500,000 new cases and 274,000 deaths will occur in women throughout the world. Human papillomavirus (HPV) has been designated by the World Health Organization (WHO) as a "necessary cause" of cervical cancer. There are 6.2 million new cases of HPV diagnosed each year. In addition to cervical cancer, the virus has also been implicated in vaginal, vulvar, penile, anal, and head and neck cancers. Current methods for prevention of cervical cancer include Pap smears, HPV testing, ablative procedures, cervical conization, and hysterectomy. These are costly as well as invasive. The HPV vaccine is the most recent breakthrough for the prevention of cervical cancer. The quadrivalent HPV vaccine (Gardasil) covers types 6, 11, 16, & 18. The bivalent vaccine (Cervarix) covers types 16 & 18, and is expected to come out in the early part of 2007. Approximately 70% of cervical cancer is caused by HPV types 16 & 18. HPV types 6 &11 are responsible for 90% of anogenital warts. Females of ages 11-12 and those prior to their sexual debut should be vaccinated, with all females in the age range of 9-26 also eligible. This vaccination strategy can prevent the above HPV infections, cervical dysplasia, and possibly cervical cancer.