A comparison of modified MonoPrep2™ of liquid-based cytology with ThinPrep® Pap test

Assessing the impact of lubricant on liquid-based Pap smear test outcomes: a randomized clinical trial

Background

Since today cervical cancers are growing, there is an increasing need to use screening and examination methods. Meanwhile, liquid-based Pap smear test is a common screening method for women, which is widely applied today. Studies have found that use of lubricant gel in this test can affect the pathology and cytology results. Accordingly, the authors intended to evaluate the effect of use of lubricant gel on the Pap smear test results.

Methods

This study was of single-blind clinical trial, the study population consisted of candidate patients for screening in terms of cervical pathology, for whom liquid-based Pap smear was done. In this study, 506 patients participated, divided into two groups of 253. One group used lubricant gel during the Pap smear, while the other group underwent this test without lubricant. The data were analyzed by SPSS 21.

Results

The study results indicated that once the two groups were compared in terms of age, interval of menstruation time and intercourse time from the sampling, no significant relationship was found between the two groups (P>0.05). It was also found that use of lubricant did not affect the cytology and pathology results of patients (P>0.05).

Conclusion

The use of lubricant gel in patients can reduce pain in patients during examination and testing, but does not affect the cytological and pathological results of patients.

Assessment of DNA methylation for the detection of cervical neoplasia in liquid-based cytology specimens

OBJECTIVE

DNA methylation is an early event in carcinogenesis. Testing for DNA methylation has potential in cancer screening. The aim of this study was to investigate the feasibility of methylated DNA detection as a screening tool for squamous cell carcinomas (SCC) and squamous intraepithelial lesions (SIL) in cervical scrapings.

METHODS

A multiplex, nested, methylation-specific polymerase chain reaction approach was used to examine promoter methylation of 12 genes (CDH1, DAPK, GSTP1, HIC-1, HIN-1, hMLH1, MGMT, p16, RAR-beta, RASSF1A, SHP-1, and Twist) in biopsy-proven SCC (n=69), high-grade SIL (HSIL, n=67), low-grade SIL (LSIL, n=32), and negative (n=41) liquid-based cytology samples.

RESULTS

The methylation frequency in normal, LSIL, HSIL, and SCC was significantly different (p<0.01) for eight genes (DAPK, HIC-1, HIN-1, MGMT, RAR-beta, RASSF1A, SHP-1, and Twist). There was a trend toward increasing methylation of HIN-1, MGMT, RAR-beta, RASSF1A, and SHP-1 with increasing severity of cervical squamous lesions. The number of methylated genes increased with the severity of cervical squamous lesions (p<0.001). In receiver-operating characteristic analysis, the three-gene combination (RAR-beta/Twist/MGMT) showed the best performance to distinguish HSIL/SCC from LCIS/negative samples. The estimated specificity of this three-gene panel for detecting HSIL/SCC was 82.2%, and its sensitivity was 78.7%.

CONCLUSION

Although aberrant DNA methylation has the potential to function as a molecular biomarker of HSIL and SCC in liquid-based cytology tests, additional genes that are selectively methylated in HSIL and SCC are needed to improve clinical performance.

Usefulness of liquid-based preparation in urine cytology

OBJECTIVE

ThinPrep (TP), a liquid-based cytological and non-invasive technique to confirm the diagnosis of bladder cancer, is reported to be a better screening test than the conventional cytospin method. This study compared the new MonoPrep2 (MP), a liquid-based cytological technique, with TP for diagnosing bladder cancer.

MATERIALS AND METHODS

Between January 2003 and June 2004, urine samples from 284 patients were processed using the TP and MP methods. The cytological diagnosis and the determination of specimen quality were performed separately. The cytological diagnoses were classified into four categories: unsatisfactory, benign, borderline, and malignant. A subsequent biopsy was performed in 73 patients. The cytological diagnoses were compared with the biopsy results to evaluate the sensitivity and specificity of the two methods.

RESULTS

Considering all the features examined, the overall specimen quality was comparable between the MP and TP techniques in the majority of cases. The rate of satisfactory specimens was 100% for TP and 98.6% for MP. The diagnostic capacity was similar between MP and TP. The overall sensitivities with MP and TP were 58.6 and 62.0%, respectively, and the specificities were 100 and 97.7%; the differences were not significant (P > 0.05).

CONCLUSIONS

MP and TP produced comparable results in diagnosing bladder cancer. As MP is less expensive than TP, we recommend MP as an alternative liquid-based cytology method for use in bladder cancer screening.

Repeating cytological preparations on liquid-based cytology samples: A methodological advantage?

This study investigates the rule that repeating cytological preparations on liquid-based cytology improves sample adequacy, diagnosis, microbiological, and hormonal evaluations. We reviewed 156 cases of pap-stained preparations of exfoliated cervical cells in two slides processed by DNA-Cytoliq System. After sample repeat/dilution, limiting factors affecting sample adequacy were removed in nine cases and three unsatisfactory cases were reclassified as satisfactory. Diagnosis was altered in 24 cases. Of these, the original diagnosis in 15 was atypical squamous cells of undetermined significance; after the second slide examination, diagnosis in 5 of the 15 cases changed to low-grade squamous intraepithelial lesion, 3 to high-grade squamous intraepithelial lesion, and 7 to absence of lesion. Microbiological evaluation was altered, with Candida sp. detected in two repeated slides. Repeat slide preparation or dilution of residual samples enhances cytological diagnosis and decreases effects of limiting factors in manually processed DIGENE DCS LBC.

Efficiency of an inexpensive liquid-based cytology performed by cytocentrifugations: a comparative study using the histology as reference standard

BACKGROUND

Although liquid-based cytology (LBC) is now recommended for cervical cancer screening, it requires expensive automated devices and materials. To evaluate the efficiency of inexpensive LBC methods relying on an inexpensive fixative liquid, Easyfix, we compared the results obtained by the liquid-based cytology (LBC) diagnoses performed by cytocentrifugations (Papspin and Turbitec) with those obtained by histology. Furthermore, we evaluated the efficiency of the fixative liquid, Easyfix, to preserve HPV DNA in the collected samples.

METHOD

266 LBC were compared with 174 colposcopies and 91 Loop Electrosurgical Excision Procedure (LEEP). Among the LBC, 51 were performed using the Papspin system and 215 were performed using the Turbitec system. To control the quality of the preservation liquid, Easyfix, we correlated the results of HCII assays with those of HPV PCR.

RESULTS

For Papspin and Turbitec systems, the sensitivities were respectively 82.6% (95% CI: 61.2-95.0%, p < 0.001) and 75.0% (95% CI: 64.4-89.8%, p < 0.001) and the specificities were 92.6% (95%CI: 76.5-99.1%, p < 0.001) and 96.2% (95% CI: 91.3-98.7%, p < 0.001). We find no statistical difference between the results of the both systems (p = ns). The sensitivity of the HCII was 86.4% (95% IC: 77.4-92.8%, p < 0.001) and the specificity was 39.4% (95% CI: 31.2-48.1%, p < 0.001). The comparison between HCII and HPV-PCR shows a good correlation: the kappa was 0.89.

CONCLUSION

LBC performed by cytocentrifugations are inexpensive, reduce inadequate smears, show excellent efficiency and allow HPV detection by molecular biology.