Analysis of five sampling methods for the preparation of cervical smears

The quality of the cervical smear, a decisive factor in the efficacy of population screening, can depend on the sampling method utilized. An analysis was made of the performance of five sample takers in a screening program, each of whom had made approximately 5,000 smears, and of the five sampling methods each had used: spatula alone (method A), Cytobrush plus spatula (method B), Cytopick (method C), cotton swab plus spatula (method D) and Cervex brush (method E). The differences between the sample takers and the sampling methods were significant in both the detection of grade III cervical intraepithelial neoplasia (CIN III) (P less than .01) and in the production of smears containing endocervical cells (EC+) (P less than .018). The data obtained firmly establish the importance of the presence of endocervical cells for smear adequacy. The results of this study indicate that (1) method B (Cytobrush plus spatula) and method C (Cytopick) give superior results in the preparation of EC+ smears and in the detection of CIN III and thus should be used in population screening programs, and (2) methods A and D should not be used for cervical cytologic sampling in such programs.     

Comparative evaluation of seven cell collection devices for cervical smears

OBJECTIVE: To compare the most commonly used cervical sampling devices. STUDY DESIGN: We examined seven cytology sampling devices (Cytobrush, Cervex brush, Szalay spatula, Papex spatula, WrGKK spatula [main social security agency in Vienna], cotton swab and loop). Eight hundred smears were assessed for even distribution of cells, percentage of slide surface covered with cells, and presence and number of endocervical cells. RESULTS: Even distribution of cells was best with the WrGKK spatula. Percentage of slide surface covered with evaluable cells was best with the Cytobrush. Highest ranking for the presence of endocervical cells was found for the Cytobrush. Cotton swabs and loop showed inferior results in all categories. CONCLUSION: The use of cervical cell sampling devices showing the best cytologic results improves the interpretation and validity of cervical smears. Our results suggest that cotton swabs and loops should not be used for cervical cell sampling.     

Relation between sampling device and detection of abnormality in cervical smears: a meta-analysis of randomised and quasi-randomised studies.

OBJECTIVE: To assess the diagnostic yield of different sampling devices used in cervical screening. DESIGN: Meta-analysis of randomised and quasi-randomised studies. SETTING: All randomised and quasi-randomised studies comparing the yield of cytological or histological abnormalities when two or more different sampling devices were used. SUBJECTS: 85,000 patients included in 29 studies reported in 28 papers. MAIN OUTCOME MEASURES: Pooled relative risk and 95% confidence interval of the yield of mild dysplasia or worse in smears recovered by each sampling method versus each other method with which it was compared; sensitivity or positive predictive value, or both, of cytological versus histological results in six studies from which sufficient data were available. RESULTS: There were no substantial differences in the yield of cytological abnormalities between the Ayre spatula, the Cytobrush, and the cotton swab used alone. There were also no substantial differences in the yield of cytological abnormalities between the extended tip spatula, the Ayre spatula combined with the Cytobrush or cotton swab, or the Cervex brush. The Ayre spatula, Cytobruah, or cotton swab used alone generally performed significantly worse than the combinations, the extended tip spatula, or the Cervex brush. There were no substantial differences in sensitivity or positive predictive value between the sampling methods. CONCLUSIONS: These results support the use of either the extended tip spatula, a combination of any spatula plus the Cytobrush or cotton swab, or the Cervex brush for cervical screening.     

Comparison of spatula and nonspatula methods for cervical sampling

A comparison between nonspatula (cotton swab and Cytobrush) cervical sampling methods and spatula (wooden Ayre spatula and plastic extended-tip Szalay Cyto-Spatula) sampling methods was made in 109 cases. Based on the presence of endocervical cells, there were statistically significant qualitative differences between the non-spatula methods as well as between the spatula methods, but not between the Cytobrush and Cyto-Spatula smears or the cotton swab and Ayre spatula smears. In all kinds of inflammatory lesions, the spatula samples were more accurate and diagnostic than the nonspatula ones. In all cases of cervical intraepithelial neoplasia and in most cases of squamous metaplasia, the Cyto-Spatula sample was the most accurate. It is concluded that the Szalay Cyto-Spatula method is superior to the other cervical sampling methods because it provides well-preserved cells from both the endocervix and the ectocervix in one smear. The Cytobrush should be used in conjunction with spatula sampling (combination method) for effective sampling of the cervix. The Cytobrush alone is effective mainly for endocervical sampling while the Ayre spatula alone is effective mainly for ectocervical sampling; the cotton swab is ineffective for both endocervical and ectocervical sampling.     

Cervex brush versus vaginal–cervical–endocervical (VCE) triple smear techniques in cervical sampling

Cervex brush versus vaginal–cervical–endocervical (VCE) triple smear techniques in cervical sampling
Cervex brush sampling was compared with the conventional triple vaginal–cervical–endocervical (VCE) smear technique. Nine hundred and fifty‐nine Cervex brush smears and 1064 VCE smears were studied. All smears with both methods were technically satisfactory for evaluation. Endocervical cells were found in 90.7% and metaplastic cells in 73.3% of Cervex brush samples and in 92.5% and 64.1% of VCE samples, respectively. There were significantly more metaplastic cells in smears from premenopausal women. Low grade squamous intraepithelial lesion (SIL) was found in three Cervex brush samples and in two VCE samples. High‐grade SIL was found only in one Cervex brush sample. Benign cellular changes were found in 142 Cervex brush samples and in 144 VCE samples. Sampling with the Cervex brush is efficient, simple and fast and gives high quality cervical smears for cytological evaluation.     

Adequacy of cervical cytology sampling with the Cervex brush and the Aylesbury spatula: a population based randomised controlled trial.

OBJECTIVE: To compare the adequacy of cervical cytology sampling with two sampling instruments commonly used in primary care-namely, the Aylesbury spatula and the Cervex brush. DESIGN: Pair matched, population based randomised controlled trial. SETTING: 86 general practices and family planning clinics in Greater Manchester. SUBJECTS: 15 882 cervical smears taken from women aged 20-64 years as part of the national cervical screening programme. INTERVENTIONS: Participating centres were allocated to sample with either the Cervex brush or the Aylesbury spatula. MAIN OUTCOME MEASURE: Inadequate smear rate. RESULTS: 5.4% and 5.5% (433/8086 and 426/7796) of smears taken with the Cervex brush and the Aylesbury spatula respectively were reported as inadequate (odds ratio 0.95; 95% confidence interval 0.74 to 1.22). CONCLUSION: The Cervex brush offers no advantage over the Aylesbury spatula in reducing inadequate smear rates in the primary care setting.     

Improved endocervical sampling with the Cytobrush.

OBJECTIVE: To evaluate the effectiveness of the Ayre wooden spatula, the cotton-tipped swab and the Zelsmyr Cytobrush in obtaining endocervical cells. DESIGN: Cross-sectional comparison study. SETTING: Family practice unit. PATIENTS: All postpubertal, nonpregnant women who underwent a routine Papanicolaou smear during a 7-month period. INTERVENTIONS: The three devices were used in each patient in a randomized sequence. An experienced cytotechnologist blinded to the device used evaluated the slides for overall epithelial cellularity (graded from 0 [acellular specimen] to 12 [overloaded sample]), density (the number of groups of five or more endocervical cells) and size of cell clusters (5 to 10 cells per cluster [score of 1], 11 to 100 [2] or more than 100 [3]). MAIN RESULTS: Samples from 2 of the 136 women were rejected because of improper labelling of the slides or failure to use all three devices. Seventy-six (57%) of the smears obtained with the spatula and 71 (53%) with the swab had no endocervical cells, as compared with only 14 (10%) obtained with the Cytobrush (p = 0.001). The overall cellularity (and standard deviation [SD]) of the smears obtained with the Cytobrush (5.69 [SD 1.17], p = 0.001) and the spatula (5.70 [SD 1.46], p = 0.001) was significantly greater than the cellularity of those obtained with the swab (4.31 [SD 1.17]). The Cytobrush yielded significantly more groups of endocervical cells (109.84 per slide) than either the spatula (4.17) or the swab (6.25) (p = 0.001). The Cytobrush also produced larger cell clusters (1.56 [SD 0.67], p = 0.001) than either the swab (0.83 [SD 1.70]) or the spatula (0.64 [SD 0.67]). CONCLUSIONS: The Cytobrush and the spatula should be used instead of the spatula alone or the spatula and the swab for collecting endocervical cells.     

Use of the Cytobrush for cervical sampling after cryotherapy

The presence of endocervical cells in routine gynecologic smears (prepared from spatula and cotton swab samples) and Cytobrush smears was analyzed in 52 patients with a history of prior cryotherapy. These cases represented 11% of the 491 women evaluated using both techniques between August 1, 1987, and January 31, 1990. The routine smear contained endocervical cells in 25 (48%) of the 52 cases while the Cytobrush smear contained endocervical cells in 49 (94%) of the cases. The use of the Cytobrush for cervical cytologic screening thus appears to be of value in patients with a prior history of cryotherapy, which frequently renders the transformation zone less accessible to routine sampling.     

Comparison of Cytobrush sampling, spatula sampling and combined Cytobrush-spatula sampling of the uterine cervix

Since the introduction of the Cytobrush for sampling the uterine cervix, some practitioners have ceased taking a concomitant cervical scraping using a spatula. To examine whether Cytobrush sampling alone is adequate for the diagnosis of cervical lesions, the Cytobrush and spatula samples in 444 smears (most with original diagnoses of at least mild dysplasia) were analyzed separately for the presence of diagnostic cells, endocervical cells and squamous cells. Of the 412 smears showing pathologic findings (mild to severe dysplasia or worse), diagnostic cells were present in 400 Cytobrush samples and in 369 spatula samples; the combination of both samples thus gave a 3% gain in correct diagnoses as compared to use of the Cytobrush samples alone. Another 18 smears would have been underdiagnosed based only on the Cytobrush samples. Endocervical cells were present in 95.3% of the Cytobrush samples and 83.8% of the spatula samples; squamous cells were present in 93.9% of the Cytobrush samples and 96.8% of the spatula samples. Analysis confirmed that it is important that the smear should contain both endocervical and squamous cells. A positive relationship between the absence of squamous cells in the Cytobrush sample and the probability of a false-negative assessment was suggested. It thus seems inadvisable to replace the combination sampling method by Cytobrush sampling alone, which may lead to a false-negative diagnosis.     

The Cervex: an ectocervical brush sampler

The performance of a new ectocervical brush sampler--the Cervex--was compared with the Ayre spatula in 280 paired cervical smears. The Cervex smears were superior in quality of spread, transformation zone sampling in all degrees of cervical patency and in detection of histologically proven epithelial abnormalities, with a false negative rate of 10.9% compared with 20% for the Ayre. Improvement in predictive value was noted in atrophic samples, with increased cellularity and transformation zone representation. Difficulty has been encountered in obtaining adequate samples from the older woman and from those with iatrogenic scarring of the cervix. Although two-sampler techniques may be used, submission of high quality pan-cervical material from a single sampler onto one slide is economically and organizationally attractive. The Cervex seems capable of producing such samples and deserves further evaluation for routine screening.     

A comparison between the Accu-Pap device and the extended-tip wooden Ayre spatula for cervical cytology sampling

The wooden Ayre spatula with an extended endocervical tip was compared with both designs of the plastic Accu-Pap sampler in two series of 100 consecutive patients to compare their adequacy in obtaining samples for cervical cytology. There was no significant advantage noted in the smears taken by either spatula. In terms of the sequence of smears, the second smear generally contained more endocervical cells and less often showed an absence of diagnostic cells.     

Collection devices for cervicovaginal cytology: a comparison

OBJECTIVE: To compare cervicovaginal smears obtained by a cotton-tipped swab with those obtained by cervix brush and modified Ayre spatula. STUDY DESIGN: A combined cervicovaginal smear was collected from 100 women using 3 different collection devices: cotton-tipped swab, cervix brush, and modified Ayre spatula. In each patient a set of 3 smears was collected by the same cytotechnologist using all 3 devices in random order. Smears were evaluated using parameters mandatory for an optimal smear: evenly dispersed, well-preserved, adequate cells from the transformation zone. The cost and availability of the collection devices were also considered. RESULTS: The swab was the most effective device in obtaining thin, evenly spread, adequate, well-preserved smears as against the cervix brush and Ayre spatula. The pickup of abnormal cells was similar with the cotton-tipped swab and cervix brush, while the Ayre spatula failed to yield high grade squamous intraepithelial lesions, atypical glandular cells of undetermined significance and adenocarcinoma cells. The cotton-tipped swab proved to be the most cost effective. CONCLUSION: A properly prepared cotton-tipped swab is an inexpensive, readily available, nontraumatic collection device that yields smear of optimal quality.     

Consequences of the introduction of combined spatula and Cytobrush sampling for cervical cytology. Improvements in smear quality and detection rates

One of the most important yardsticks for evaluating sampling for the detection of premalignant and malignant cervical lesions is the percentage of smears that contain cells from the transformation zone. Until February 1985, all smears made by around 500 different general practitioners were taken with a modified Ayre spatula. In the period February to October 1985, 24,496 smears of spatula samples and 5,716 smears prepared by combined spatula-Cytobrush sampling were analyzed. With the introduction of the combined spatula-Cytobrush method, the rate of smears containing cells from the transformation zone (adequate smears) rose from 84% to 98%. With the spatula-alone method, there were large differences between the rates of adequate smears from the various doctors; with the combined spatula-Cytobrush method, all participating doctors were without exception highly successful. The positive cytology rate was significantly higher in the combined spatula-Cytobrush smears (0.75%) as compared with the spatula-alone smears (0.38%). There was also a change in the diagnostic pattern in that more premalignant changes of the glandular epithelium of the endocervix were detected. One case of early invasive adenocarcinoma of the endocervix, in which the combined spatula-Cytobrush smears was positive and the repeat spatula-alone smear made by the gynecologist was negative, is discussed in detail. We anticipate that, with the large-scale introduction of the Cytobrush sampling method, fewer repeat smears will be required and, in addition, the observed relative increase of endocervical adenocarcinoma of the endocervix will be halted. In addition, there will be fewer false-negative smears.     

Diagnostic accuracy of squamous cervical lesions studied in spatula-cytobrush smears

The cytologically positive cases found in 25,300 cervical smears of spatula samples and 6,168 smears prepared by combined spatula-Cytobrush sampling were analyzed. The diagnostic accuracy (the correlation between the cytologic and histologic diagnoses) was the same for both types of sampling. As to the histologic diagnosis, the rates of severe dysplasia, carcinoma in situ and squamous carcinoma in the spatula-Cytobrush group were more than twice as high as in the spatula group. In the spatula group, the majority of abnormal cells was of the mature type. In the spatula-Cytobrush group, the majority of smears contained a mixture of immature and mature abnormal cells. The more immature lesions, which are often located higher in the endocervical canal, seem to be better sampled by the Cytobrush. The results indicate that the Cytobrush reaches areas that a spatula cannot reach, resulting in a higher diagnostic efficiency.     

Reporting of an Endocervical Component After A Previous Cervical Biopsy

The rate of reporting endocervical cells in the Papanicolaou smears of 579 women with a past history of cervical biopsy was compared with an age matched control group of women. During a time period when only spatulae (Ayre Lerner and Aylesbury) were used for sampling, 55% of the cases and 53% of the controls had the presence of endocervical cells reported. When cytobrushes as well as spatulae were used, the proportion rose to 70% for cases and 73% for controls. We conclude that the probability of endocervical cells being reported is not influenced by a past history of cervical biopsy, but is substantially improved if a combination of cytobrush and spatula is provided for sampling.     

The efficiency of the Cytobrush versus the cotton swab in the collection of endocervical cells in cervical smears

In 30 patients whose last cervical smear had lacked endocervical cells, two new samples were collected, one with a cotton-tipped applicator and the other with the recently developed Cytobrush cervical brush. With the cotton swab, no endocervical cells were present in the repeat smears of 21 patients, as compared with only 3 Cytobrush smears lacking endocervical cells; the difference is statistically significant (P less than .001). Quantitatively, the cellular yield with the Cytobrush was larger. It is concluded that the use of the cervical brush to collect material for cervical smears is more effective and provides a higher yield of cells than the use of the conventional cotton swab. The importance of the presence of endocervical cells in a smear as evidence that the transformation zone has been properly sampled is also discussed.     

Pap smear quality parameters of 3 sampling devices used by auxiliary nurse midwives on symptomatic rural Indian women

OBJECTIVE: To determine whether auxiliary nurse midwives (ANMs) could make good-quality Pap smears after focused training and to determine which sampling device is most effective in their hands in field practice areas. STUDY DESIGN: In a downstaging cervical cancer screening program, 394 symptomatic rural Indian women between the ages of 35 and 60 were identified by the ANMs in 2 villages, with a total population of 14,747, and were invited to have a smear taken. Two hundred of these symptomatic women responded. The ANMs were educated to render information on screening for cervical cancer and to take smears with 3 sampling devices--Ayre spatula, modified spatula (with extended tip) and Cytobrush (Medscand AB, Malm?, Sweden). The smears were evaluated for 6 adequacy parameters. Smears made by gynecologists were used as controls. To establish the superiority of a method, chi2 tests were used. RESULTS: All smears made by the ANMs could be used to render a cytologic diagnosis. The adequacy parameters of all the smears made by ANMs at least matched those of the gynecologists. The best results were obtained with modified spatula (with extended tip) and combination of Cytobrush with modified spatula. CONCLUSION: Since only 50% of symptomatic rural women came for Pap testing, we conclude it is not easy to motivate women for such testing, even if a large-scale educational effort is made. ANMs can be taught to take reasonably good qualisuperior sampling device for ANMs is ty Pap smears. The superior sampling device for ANMs is the modified spatula (with extended tip).     

The effects of different sampling techniques on smear quality and the diagnosis of cytological abnormalities in cervical screening

A major cause of false‐negative cervical smears is sampling error. We examined the results obtained with three different instruments in 126 608 smears from general practitioners. The spatula/brush combination yielded the highest proportion of smears showing cytological abnormalities, and the Cervex brush the lowest. Although not a randomized study, this paper highlights the shortcomings of the Cervex brush. We postulate a mechanical deficiency. Diagnostic accuracy rather than a high proportion of good quality smears should dictate the choice of instrument.     

Quality grading for cervical smears

Three thousand five hundred and eighty cervical smears were taken in 1990–1992 at a Genitourinary Medicine Clinic with various spatula or spatula brush combinations. the unsatisfactory rate and the detection of cellular abnormalities showed some relation to spatula type. However, the satisfactory smears screened in the laboratory are routinely assigned a quality grade-good, fair or poor. Analysis shows higher rate of detection of cellular abnormalities in good quality smears, the detection of dyskaryosis being twice as high, in contrast to the fair or poor quality smears. It is suggested that quality grade is a better way of classifying smear quality in the cervical screening programmes rather than the presence or absence of endocervical and/or metaplastic cells.     

Exact Touch: a new device for cervical cytology. Comparison with Ayre spatula plus Cytobrush

Exact Touch is a new plastic device for the collection of cells from the ectocervix and endocervix. A total of 189 consecutive women were evaluated, 94 with the Ayre/cytobrush and 95 with Exact Touch. Sampling was performed by only one clinician, and the slides were analysed by only one cytotechnologist, who had no information about the sampling method. Our results showed that more endocervical and metaplastic cells were collected by Exact Touch than by Ayre/cytobrush.