Effects of transitioning from conventional methods to liquid-based methods on unsatisfactory Papanicolaou tests: results from a multicenter US study

Navigating Practice Issues Related to the Unsatisfactory Cervicovaginal Papanicolaou Test: Survey Results of Laboratories Participating in the 2020 College of American Pathologists PAP Education Program

CONTEXT.—

Unsatisfactory Papanicolaou (Pap) tests pose a unique set of challenges to the laboratory with regard to their processing, review, reporting, and performance of human papillomavirus (HPV) testing. There are no standardized guidelines for the review process and handling of unsatisfactory Pap tests.

OBJECTIVE.—

To assess the current practice patterns regarding various aspects of the unsatisfactory Pap test, from processing to reporting, across laboratories worldwide.

DESIGN.—

A supplemental questionnaire was mailed to laboratories participating in the 2020 College of American Pathologists (CAP) Gynecologic Cytopathology (PAP Education) Program, requesting data regarding the unsatisfactory Pap test.

RESULTS.—

Of 1520 participating laboratories, 619 (40.7%) responded, and the responses of 577 laboratories were included for further analysis. Only 64.6% (373 of 577) laboratories used the unsatisfactory Pap test criteria as specified by the 2014 Bethesda System. About three-quarters of the respondents (433 of 576; 75.2%) routinely rescreened unsatisfactory Pap tests. Routine repreparation of such Pap tests was performed by 54.9% (316 of 576) of laboratories, and 52.0% (293 of 563) used glacial acetic acid for repreparing excessively bloody specimens. HPV test results were reported for unsatisfactory Pap tests, always or sometimes, by 62.4% (353 of 566) of respondents.

CONCLUSIONS.—

This CAP survey reveals important information regarding the practice patterns pertaining to several aspects of the unsatisfactory Pap test. It also provides valuable insight into the quality assurance measures that can be implemented for such tests. Future studies can further aid in the standardization of all components of the handling of unsatisfactory Pap tests for overall quality improvement.

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.

Comparison of Unsatisfactory Samples from Conventional Smear versus Liquid-Based Cytology in Uterine Cervical Cancer Screening Test

BACKGROUND

Cervical cytology for uterine cervical cancer screening has transitioned from conventional smear (CS) to liquid-based cytology (LBC), which has many advantages. The aim of this study was to compare the proportion of unsatisfactory specimens from CS versus LBC at multiple institutions including general hospitals and commercial laboratories.

METHODS

Each participating institution provided a minimum of 500 Papanicolaou (Pap) test results for analysis. Pap tests were classified according to the participating institution (commercial laboratory or general hospital) and the processing method (CS, ThinPrep, SurePath, or CellPrep). The causes of unsatisfactory results were classified as technical problems, scant cellularity, or complete obscuring factors.

RESULTS

A total of 38,956 Pap test results from eight general hospitals and three commercial laboratories were analyzed. The mean unsatisfactory rate of LBC was significantly lower than that of CS (1.26% and 3.31%, p = .018). In the LBC method, samples from general hospitals had lower unsatisfactory rates than those from commercial laboratories (0.65% vs 2.89%, p = .006). The reasons for unsatisfactory results were heterogeneous in CS. On the other hand, 66.2% of unsatisfactory results in LBC were due to the scant cellularity.

CONCLUSIONS

Unsatisfactory rate of cervical cancer screening test results varies according to the institution and the processing method. LBC has a significantly lower unsatisfactory rate than CS.

Comparison of Unsatisfactory Samples from Conventional Smear versus Liquid-Based Cytology in Uterine Cervical Cancer Screening Test

BACKGROUND

Cervical cytology for uterine cervical cancer screening has transitioned from conventional smear (CS) to liquid-based cytology (LBC), which has many advantages. The aim of this study was to compare the proportion of unsatisfactory specimens from CS versus LBC at multiple institutions including general hospitals and commercial laboratories.

METHODS

Each participating institution provided a minimum of 500 Papanicolaou (Pap) test results for analysis. Pap tests were classified according to the participating institution (commercial laboratory or general hospital) and the processing method (CS, ThinPrep, SurePath, or CellPrep). The causes of unsatisfactory results were classified as technical problems, scant cellularity, or complete obscuring factors.

RESULTS

A total of 38,956 Pap test results from eight general hospitals and three commercial laboratories were analyzed. The mean unsatisfactory rate of LBC was significantly lower than that of CS (1.26% and 3.31%, p = .018). In the LBC method, samples from general hospitals had lower unsatisfactory rates than those from commercial laboratories (0.65% vs 2.89%, p = .006). The reasons for unsatisfactory results were heterogeneous in CS. On the other hand, 66.2% of unsatisfactory results in LBC were due to the scant cellularity.

CONCLUSIONS

Unsatisfactory rate of cervical cancer screening test results varies according to the institution and the processing method. LBC has a significantly lower unsatisfactory rate than CS.

Follow-up and clinical significance of unsatisfactory liquid-based Papanicolaou tests

BACKGROUND

To the authors' knowledge, few studies to date have examined adherence to recommended guidelines for follow-up and outcomes after an unsatisfactory Papanicolaou (Pap) test (UPT) with liquid-based technologies.

METHODS

Within 4 US health plans, the median time to follow-up and the percentage of patients with follow-up testing by 120 days was calculated after a UPT. Multivariable analyses evaluated the association between clinical factors and follow-up testing. The authors compared the risk of a diagnosis of cervical intraepithelial neoplasia of type 2 or worse (CIN2+) after a UPT with the risk after a satisfactory Pap test while controlling for study site, test year, and other covariates.

RESULTS

A total of 634,644 Pap tests performed between 2004 and 2010 were included in the current study. Of 1442 UPTs, 53.4% had follow-up testing within 120 days; follow-up differed across the health plans (P<.001) and was found to be higher among patients aged <50 years (57.2% vs 48.8%; P = .01) and those with positive human papillomavirus (HPV) results (84.6% vs 53.9; P <.01). The risk of CIN2+ was similar for patients with both unsatisfactory and satisfactory Pap tests. However, after a UPT, the variables of age <50 years, having no previous history of Pap testing, having a history of a previous abnormal Pap test, and positive HPV status were all found to be risk factors for CIN2+; a positive HPV test was found to be the strongest risk factor for developing CIN2+. A negative HPV test result was protective for a CIN2+ diagnosis.

CONCLUSIONS

Various clinical factors associated with the risk of CIN2+ appear to influence the receipt of follow-up after a UPT. HPV test results in patients with UPTs might be used in follow-up strategies; specifically, a negative test result might reduce the urgency for repeat Pap testing.

Common causes for unsatisfactory Pap tests in a high-risk population: insights into a yet unresolved problem in gynecologic cytology

INTRODUCTION

Although the rates are generally low (0.2%-10%), unsatisfactory Papanicolaou (Pap) tests are associated with an increased risk of epithelial lesions on subsequent follow-up. Therefore, some studies have recommended extra laboratory processing, resampling of patients, and more recently, human papillomavirus testing.

MATERIALS AND METHODS

Consecutive cases signed out as unsatisfactory for evaluation (UE) were identified from January 1, 2008 to December 31, 2010 in the cytology laboratory at Houston Methodist Hospital. Patient's demographics, relevant prior clinical history, type of Pap test, reasons for UE diagnosis, and cytology or histology follow-up were obtained from the pathology database.

RESULTS

Among 56,563 total Pap tests, 276 were signed out as UE (0.47%). Nearly half of these patients were older than 50 years (15 to 88 years). The majority (85%) of patients over 50 years old had a history of prior gynecologic cancer. Low squamous cellularity was the most common cause of UE in all age groups. Follow-up abnormalities were identified in 21 of 73 patients (29%).

CONCLUSIONS

Low squamous cellularity was the most common cause of UE and was often seen in women older than 50 years of age. The significant risk associated with UE emphasizes the importance of appropriate follow-up on these patients.