Test characteristics of various screening modalities for cervical cancer: a feasibility study to develop an alternative strategy for resource-limited settings

OBJECTIVE: To determine test characteristics - sensitivity, specificity, positive and negative predictive values - of different screening modalities to detect cervical precancerous and cancerous lesions in order to devise an effective alternative strategy for cervical cancer screening in resource-poor settings. METHODS: A total of 472 women presenting with nonspecific gynecologic symptoms were screened by cytology, visual inspection with acetic acid application (VIA), VIA with magnification (VIAM) and human papillomavirus (HPV)-DNA testing. Colposcopic examination was performed in all and on-site biopsy was taken if any grade I and above lesion was detected on colposcopy (230). On histopathological examination, 105 showed cervical intraepithelial neoplasia II and above lesions. Sensitivity, specificity and predictive values for each test were calculated taking colposcopy and or directed biopsy as the gold standard. Comparisons were made with cytology in order to assess the feasibility of alternative strategies in resource-poor settings. RESULTS: VIA was less sensitive (86.7% versus 91.4%) but more specific (90.7% versus 86.6%) than cytology at low grade squamous intraepithelial lesion (LSIL) threshold but the difference was not statistically significant (P > 0.01). HPV testing improved the sensitivity over cytology (97.1% versus 91.4%) but there was a nonsignificant loss of specificity (84.2% versus 86.6%). Results of VIAM were more or less similar to VIA. CONCLUSION: VIA can be used as a mass screening tool for cervical cancer in resource-poor settings.     

The quality of smear taking training for hospital medical trainees

INTRODUCTION: Training for cervical smear takers in primary care is well established. We aimed to assess the adequacy of training in cervical smear taking among hospital medical trainees. METHOD: An anonymous questionnaire survey was conducted among hospital medical trainees within the North West region of England. The questionnaire assessed the trainees' level of confidence in their knowledge and skills in the theoretical and practical aspects of cervical smear taking, and the training they had received. The standards used were as stated in the National Health Service Cervical Screening Programme Resource Pack for Training Smear Takers (July 1998). These included practical smear taking, pre- and post-test counselling, the background to cervical screening, the National Health Service Cervical Screening Programme, the role of the Health Authority and the laboratory, provision for women with special needs, acceptability, accountability and quality assurance. RESULTS: Seventy-eight per cent of trainees returned the questionnaires. Although all the trainees were confident about taking smears, a significant percentage was concerned about the theoretical and specific issues associated with smear taking such as the care of women with special needs. Only 60.7% had received formal training in practical smear taking. Furthermore, only 48.3% had been formally trained in the clinical management of smears. CONCLUSION: There appears to be an urgent need for formal training in the theory and practice of smear taking and for the standardization of the course content. The introduction of training in liquid-based cytology provides us with a golden opportunity to address this deficit.     

Improving the NHS cervical screening laboratory performance indicators by making allowance for population age, risk and screening interval

OBJECTIVE: One of the key performance measures in the monitoring of the NHS cervical screening programme is the targeting of laboratories with very high or low percentages (outside the 10th-90th percentile) of adequate smears that have moderate dyskaryosis or worse. These laboratories are assumed to include those laboratories that may have extremes of sensitivity and specificity. A clear limitation with this methodology is that laboratories do not examine smears from women with the same underlying risk, age distribution or screening interval and adjustment for these factors should considerably improve the method. METHODS: This paper describes a method that allows for these confounding variables and a new age-risk-interval adjusted moderate dyskaryosis or worse rate (ARI-adjusted mod+ rate) can be calculated. The adjusted rate is the rate of moderate or worse dyskaryotic smears that the laboratory would have detected had it been screening women with an English 'average' age-risk-interval. All laboratories can therefore be compared using this method. RESULTS: The methodology is illustrated using data from the NHSCSP South West Region. The particularly low percentage of moderate or worse smears detected by one or two laboratories can be shown to be due to a local screened population with a very low risk because of a high mean age, relatively short screening interval and census variables associated with a low risk, rather than any under-calling by the associated laboratories. CONCLUSIONS: The ARI-adjusted mod+ rate requires to be calculated for all laboratories in England if it is to be used as a primary performance indicator. Alternatively, it can be used to further examine laboratories that are deemed to be outliers using the current methodology.     

Cytological diagnosis of basal cell carcinoma and actinic keratosis, using Papanicolaou and May–Grünwald–Giemsa stained cutaneous tissue smear

Objective:  Cytology may become the diagnostic method of choice with the advent of new non-invasive treatments for non-melanoma skin cancer, as the sampling technique for cytology entails little tissue disfiguration. The aim of this study was to compare and evaluate the diagnostic performance of scrape cytology using two different cytological staining techniques, and to evaluate additional touch imprint cytology, with that of histopathology of basal cell carcinoma (BCC) and actinic keratosis (AK).
Methods:  We investigated 50 BCC and 28 AK histologically verified lesions, from 41 and 25 patients, respectively. Two separate skin scrape samples and one touch imprint sample were taken from each lesion. The smears were stained with Papanicolaou (Pap) or May–Grünwald–Giemsa (MGG) stains. All cytological specimens were examined in random order by pathologists without knowledge of the histology. Cytodiagnostic results were compared with the histopathological report.
Results:  Scrape cytodiagnosis agreed with histopathology in 48 (Pap) and 47 (MGG) of the 50 BCC cases, and in 26 of 28 (Pap) and 21 of 26 (MGG) AK cases, yielding sensitivities of 96%, 94%, 93% and 81%, respectively. No significant difference in sensitivity between the two staining methods was found but a trend towards higher Pap sensitivity for AK was noted ( P  =   0.10). Touch imprint cytology confirmed histopathology in 38 of the 77 cases of BCC and AK.
Conclusion:  Cytological diagnosis with either Pap or MGG stain for BCC and AK is reliable, and differentiates well between BCC and AK. Imprint cytology proved to be non-diagnostic in half of the examined cases.     

Intraoperative cytology of clear cell carcinoma of the ovary

OBJECTIVE: To describe the cytomorphology of clear cell carcinoma (CCC) of the ovary in intraoperative samples of peritoneal fluid, imprint and scraping samples of the tumour tissue. STUDY DESIGN: Fourteen histologically confirmed cases, stained by standard cytological procedures, were analysed by light microscopy. RESULTS: In 33.3% of peritoneal fluid samples and 92.9% of imprint and scraping cytological samples, besides variable clear cell cellular morphology, one or both distinct cytological characteristics were observed: eosinophilic, hyaline, extracellular, globular substance with or without formation of a 'raspberry' body and an eosinophilic, intracytoplasmic inclusions. These structures were clearly seen only in samples stained by May-Grünwald-Giemsa. CONCLUSION: Using cytological analysis of imprint and scraping samples of ovarian tumours it is possible to make a precise intraoperative cytological diagnosis in most cases of CCC of the ovary.     

Interlaboratory reproducibility of atypical glandular cells of undetermined significance: a national survey

OBJECTIVE: The aim of this study was to evaluate the inter-laboratory reproducibility for atypical glandular cells (AGC) (The Bethesda System (TBS) 2001) of the laboratories involved in the screening programmes in Italy. METHODS: A set of 35 selected slides were circulated among 167 laboratories involved in local population-based cervical screening programmes. Each laboratory provided one single diagnosis per smear. The smears were read blind to the original diagnosis and to the diagnoses provided by other laboratories. A 'majority' diagnosis was defined for each case and assumed as the reference standard. The diagnosis provided from each laboratory was compared with the majority diagnosis. RESULTS: According to the majority report the 35 slides in the set were classified as negative in nine cases, AGC in eight, adenocarcinoma in eight, and squamous lesion or squamous + glandular lesion in 10. The crude agreement between all pairs of laboratories was 49.43%. K-values were 0.46, 0.21, 0.34, 0.36 and 0.32 for negative, AGC/AIS (adenocarcinoma in situ of endocervix), AdenoCa, Sq/Sq + Gl and all reporting categories respectively. Concordance according to overall K was moderate to substantial in 77% of the participating laboratories. CONCLUSIONS: The present study shows that the AGC category is not easily reproducible. The data confirmed the importance, in a screening scenario, of AGC/AIS diagnoses, but also presented difficulties in differentiating between the two diagnoses. In addition to the results obtained from the circulation of the slides, laboratories which had annually a low number of cervical smears were able to gain experience focused on particular morphological pictures.     

Improved endocervical sampling and HPV viral load detection by Cervex-Brush® Combi

OBJECTIVE: Liquid-based cytology (LBC) for cervical screening is becoming increasingly used. Together with SurePath LBC, various collecting devices can be utilized, among which the Cervex-Brush is the most widely used. The new Rovers Cervex-Brush Combi combines the advantages of the Cervex-Brush with the EndoCervex-Brush increasing sampling of the endocervical canal. The objective of this study was to analyse and to compare the Cervex-Brush Combi with the Cervex-Brush for the collection of squamous and endocervical cells, human papillomavirus (HPV) typing/quantification and disease detection in SurePath LBC. METHODS: Using either the Cervex-Brush or the Cervex-Brush Combi 100 consecutive SurePath LBC samples were collected using each brush type. All 200 slides were read by the FocalPoint and screened by guided screening using slide wizards. The viral load of HPV type 16 E7, 18 E7, 31 E6, 33 L1, 33 E6, 35 E4, 39 E7, 45 E7, 51 E6, 52 L1, 52 E7, 53 E6, 56 E7, 58 L1, 58 E6, 59 E7, 66 E6 and 68 E7 was determined using a TaqMan-based real-time quantitative PCR analysis. RESULTS: The mean number of sampled squamous cells did not differ between the two brush types (54 963 versus 54 595 cells). The use of the Cervex-Brush Combi, however, resulted in a two- to threefold increase in the number of sampled endocervical cells (P < 0.00001). Using the Cervex-Brush Combi slightly more lesions were detected (three versus two low-grade squamous intraepithelial lesions), and resulted in the detection of more atypical squamous cells of undetermined significance (six versus three). In the Cervex-Brush group, 60% (3/5) of abnormal smears were positive for oncogenic HPV types, whereas 66.7% (6/9) of abnormal smears in the Cervex-Brush Combi group tested positive. The median HPV viral load for samples taken with the Cervex-Brush Combi was 0.1825 copies/cell and was significantly higher than in samples taken with the Cervex-Brush (0.0042 copies/cell) (P = 0.02). CONCLUSION: Sampling with the Cervex-Brush Combi resulted in the collection of the same amount of squamous cells, but in a two to threefold harvest of endocervical cells. This led to the detection of a higher viral load for oncogenic HPV and an increase in the number of detected abnormal smears.     

Colposcopic management of high‐grade referral smears: a retrospective audit supporting ‘see and treat'?

OBJECTIVE: The National Health Service Cervical Screening Programme monitors the quality of colposcopy services through the annual KC65 returns. The 2002 returns demonstrated that Standard 7c, which specifies a biopsy rate > or = 90% at first colposcopy visit for high-grade referrals, was not met in the assessed 3-month period. This was investigated along with the other standards. METHODS: Retrospective colposcopy records were accessed for the 597 new referrals, excluding 10 pregnant patients, seen at the colposcopy clinic at the Royal Victoria Infirmary between 1 July 2001 and 31 December 2002, following an abnormal high-grade smear. Cytology and histopathology computer records were checked for confirmation. The results were assessed against the colposcopy standards applicable at that time and the revised standards (2004). RESULTS: Biopsies were taken from 94.47% (Standard > or = 90%) of women at index colposcopy visit including wire loop excision biopsies from 66.16% (87.97% of high-grade colposcopic appearances). Cervical intraepithelial neoplasia (CIN) on histology was found in 91.79% in the study group (Standard > or = 85%) and in 96.71% of index visit biopsies (Standard > or = 90%), meeting the applicable colposcopy standards. The revised 2004 standards specify a biopsy in > or = 95% of high-grade referrals and excision biopsies in 95% if colposcopic appearances are also high-grade, if colposcopy is low grade but the smear is severely dyskaryotic, or when the lesion extends into the canal. The positive predictive value of high-grade cytology for this entire group was 75.54% with CIN present in 90.95%. CONCLUSION: From this study it appears that high-grade cytology in this centre reliably indicates high-grade CIN. Therefore, in women referred for colposcopy following a high-grade smear, excision biopsies should be performed in a higher proportion at the first visit to comply with the revised standards.     

The detection of genital tract infection by Papanicolaou-stained tests

A variety of cytological changes suggestive of genital tract infection may be noted during microscopy of a Papanicolaou-stained cervical smear. The dilemma faced by cytopathologists is whether or not to report suspicious changes to the clinician responsible for the woman's care. This review examines the effectiveness of Papanicolaou-smear microscopy in the diagnosis of the more common sexually transmitted infections, and aims to encourage debate on the reporting of suggestive cytological changes.     

European guidelines for quality assurance in cervical cancer screening: recommendations for collecting samples for conventional and liquid-based cytology.

The current paper presents an annex in the second edition of the European Guidelines for Quality Assurance in Cervical Cancer Screening. It provides guidance on how to make a satisfactory conventional Pap smear or a liquid-based cytology (LBC) sample. Practitioners taking samples for cytology should first explain to the woman the purpose, the procedure and how the result will be communicated. Three sampling methods are considered as acceptable for preparing conventional Pap smears: (i) the cervical broom; (ii) the combination of a spatula and an endocervical brush; and (iii) the extended tip spatula. Smear takers should take care to sample the entire circumference of the transformation zone, to quickly spread the cellular material over a glass slide, and to fix the preparation within a few seconds to avoid drying artefacts. According to local guidelines, one of these three methods may be preferred. Sampling with a cotton tip applicator is inappropriate. Similar procedures should be followed for sampling cells for LBC, but only plastic devices may be used. The collected cells should be quickly transferred into a vial with fixative liquid according to the instructions of the manufacturer of the LBC system. Subsequently, the slide or vial and the completed request form are sent to the laboratory for cytological interpretation.     

Morphometry and digital AgNOR analysis in cytological imprints of benign, borderline and malignant serous ovarian tumours

AIM: The aim of the study was to determine values of a quantitative morphometry analysis of nuclear characteristics and argyrophilic nucleolar organizer regions (AgNORs) in differential cytodiagnosis of benign, atypically proliferating (borderline) and malignant serous ovarian tumours. METHODS: Cytological imprints of benign (n = 20), borderline (n = 19) and malignant (n = 20) ovarian serous tumours were analysed. A computerized, digital analysis was used to determine morphometric nuclear features, the number and characteristics of single AgNORs, cluster AgNORs, total AgNOR and AgNOR area/nucleus (relative area) ratio. According to their size AgNORs were classified in three categories. A one-way variance analysis and post hoc test (Scheffé) were used for statistical analysis. RESULTS: The morphometric nuclear analysis showed that benign, borderline and malignant serous ovarian tumours are statistically different (P < 0.001) according to the area and outline, the values being highest in malignant tumours and lowest in the borderline group. Digital analysis of AgNORs in benign, borderline and malignant groups showed that the total AgNOR number increases with progression of the lesion (meaning tumour malignancy) significantly (P < 0.001) between benign and malignant as well as between borderline and malignant serous ovarian tumours (P < 0.001). The progression of the lesion malignancy was accompanied by a significant (P < 0.001) progressive increase of the total and relative AgNOR area per nucleus. The AgNOR size increases from benign to malignant tumours and a statistically significant difference (P < 0.001) was observed in all three groups regarding small and large AgNORs. CONCLUSION: Combining different markers of morphometric nuclear characteristics and AgNOR values could improve differential cytodiagnosis of benign, borderline and malignant serous ovarian tumours.     

The use of digital images to evaluate the interobserver agreement on cervical smear readings in Italian cervical cancer screening

G. Tinacci, A. Biggeri, A. Pellegrini, M.P. Cariaggi, M.L. Schiboni and M. Confortini The use of digital images to evaluate the interobserver agreement on cervical smear readings in Italian cervical cancer screening Objective: The aim of this study was to measure interobserver agreement among cytologists on using a set of digital images. Methods: A set of 90 selected Papanicolaou‐stained cervical smears were digitalized and the digital images circulated among 117 readers, from laboratories spread across almost all Italian regions. Three representative fields of each smear were displayed at 20× and 40× magnification (overall six images for each case). The diagnoses made by the cytologists who provided the images were taken as target diagnoses. Results: The κ values were: very low for the categories atypical squamous cells of undetermined significance (ASC‐US), and atypical squamous cells – cannot exclude high‐grade squamous intraepithelial lesion (ASC‐H); poor for the categories atypical glandular cells (AGC), high‐grade squamous intraepithelial lesion (HSIL) and invasive cancer; and fair to good for the categories negative and low‐grade squamous intraepithelial lesion (LSIL). However, we found a cluster of 42 best concordant readers. The overall κ value and overall weighted κ with the target diagnosis for these 42 readers were 0.45 and 0.66, respectively. This finding is in contrast with the overall κ value and overall weighted κ for the other readers of 0.39 and 0.59, respectively. Conclusions: As this finding is an estimate of the accuracy of the readers, we can infer that it will be very important to reach this level of concordance for all the participating readers. Future effort will facilitate common experiences in order to improve the reproducibility of diagnostic criteria. Digital images could be the key to reach this aim.     

Assessing the wellbeing of cytoscreeners: experience in two NHS cytology laboratories

OBJECTIVE: Cervical screening programmes in England are in transition as the liquid-based cytology (LBC) method replaces conventional Papanicolaou screening and staff in NHS laboratories are trained to analyse LBC smears. Cytoscreeners and biomedical scientists undertake routine microscopy of slides, but the scientists usually have a wider professional role. Attitudinal surveys were carried out in laboratories where LBC was partially introduced. METHODS: Staff in two cytology laboratories in Greater Manchester were surveyed twice over 6 months. The questionnaire assessed work pressures using scales from the Measures of Work Characteristics instrument, work-related stress using the General Survey version of the Maslach Burnout Inventory, job intentions and job satisfaction. RESULTS: Cytoscreeners, many aged over 50 years, formed over 60% of respondents in both surveys (27/42 in the first survey), and biomedical scientists and doctors, 30%. Both groups were under moderate pressure from work demands in each survey, but cytoscreeners had significantly less autonomy over their working methods (P < 0.001). Although both groups experienced similar levels of exhaustion, cytoscreeners were much more cynical or indifferent towards work in the second survey (P = 0.008) and had lower expectations of being effective (P < 0.001). For the cytoscreeners, there were strong negative correlations in both surveys between cynicism and the work characteristics of influencing decisions and autonomy/control. CONCLUSIONS: The strength of the relationship between work performance and wellbeing serves to emphasize the importance of the new LBC technology in ameliorating low morale where it exists. Further attitudinal research involving larger samples of laboratories is warranted to assess the full impact of this innovation.     

Is urinary tract cytology still useful for diagnosis of bladder carcinomas? A large series of 592 bladder washings using a five‐category classification of different cytological diagnoses

BACKGROUND: The aim of this study was to estimate the efficiency of a recent five-category urinary cytological classification. METHODS: A total of 592 bladder washings were fixed immediately with Saccomanno's fixative. All samples were centrifuged in a Hettich cyto-centrifuge. For each sample, the reference standard was the histology when a lesion was present at the time of cystoscopy. A five-category cytological classification was used: negative, suspicious of low (S-Lg) or high (S-Hg) grade neoplasia and consistent with low (Lg) or high (Hg) grade neoplasia. RESULTS: For cytological diagnoses of S-Lg and Lg, sensitivity was 37% and specificity was 95% for the histological diagnosis of low-grade non-invasive urothelial papillary tumour (Lg-UPT), which included papillary urothelial neoplasm of low malignant potential and low-grade urothelial carcinoma. For cytological diagnosis of S-Hg and Hg, sensitivity was 44% for high-grade non-invasive urothelial papillary carcinoma (Hg-UPC), 70% for carcinoma in situ (CIS) and 81% for invasive carcinoma (T1 and higher). Specificity was 99% in each case. Cytological diagnosis of S-Hg or Hg was not found for Lg-UPT (0/59) and no cytological diagnosis of S-Lg or Lg was found for invasive carcinoma, but was seen for Hg-UPC in 10% (3/28) and for CIS in 6% (3/50) of cases. CONCLUSION: Despite the absence of international consensus, the recent five-category cytological classification for urine is accurate for current urological practice.     

Clear cell sarcoma, cellular mesoblastic nephroma and metanephric adenoma: cytological features and differential diagnosis with Wilms tumour

Wilms' Tumour (WT) is the most common kidney tumour in childhood, this fact and the embryonic complexity of WT create, whenever one of its three classical components predominates in cytologic smears, difficulties in the differential diagnoses with other less common entities. In the present study, we review the cytological and immunohistochemical characteristics of three children renal tumours, a Clear Cell Sarcoma of the Kidney (CCSK-case1), a Cellular Mesoblastic Nephroma (CMN-case2) and a Metanephric Adenoma (MA-case3) and compare them, for differential diagnostic purposes, with smears of blastematous, mesenchymal and epithelial predominant WTs, previously diagnosed in our Department. In all cases a mass was detected in the abdomen (2 and 8 year old children-cases 1 and 3, respectively), and pre-birth in case 2 (the tumour was detected during pregnancy). Fine needle biopsy was performed followed by routine cytologic examination. The presence of moderate amount of blue pale cytoplasm in neoplastic cells (case1), the presence of tightly cohesive, bland, spindle tumour cells (case2) and the identification of small, well differentiated epithelial tubules with psammoma bodies in case 3, were the main morphologic characteristics that we think represent the most important elements for distinguishing our cases from a WT. Immunoreactivity was only helpful in case 1 as we found a characteristic dot-like pattern positivity for vimentin, in the absence of immunoreactivity for the other markers that are usually positive in WT. Summing up, these three cases demonstrate that cytopathologists should be aware of the occurrence of uncommon renal neoplasms in childhood and should be acquainted with their characteristics, in order to avoid false diagnoses.     

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.     

Imprint cytology of vacuum-assisted breast biopsy specimens: a rapid diagnostic tool in non-palpable solid lesions

Objective:  Imprint cytology provides a rapid preliminary diagnosis shortly after the completion of breast biopsy. This study aims to assess the validity of imprint cytology for the pre-operative diagnosis of non-palpable mammographic solid lesions excised by vacuum-assisted breast biopsy (VABB).
Methods:  Seventy-two women with non-palpable Breast Imaging Reporting and Data System 3 and 4 mammographic solid lesions without microcalcifications underwent VABB on the stereotactic Fischer's table with 11-G Mammotome vacuum probes. Imprint samples were examined (Diff-Quick stain, modified Papanicolaou stain and May-Grünwald–Giemsa). The cores were dipped into a CytoRich Red Collection fluid for a few seconds in order to obtain samples with the use of the specimen wash. After the completion of cytological procedures, the core was prepared for routine pathological study. The pathologist was blind to the preliminary cytological results. The cytological and pathological diagnoses were comparatively evaluated.
Results:  The sensitivity of the cytological imprints for cancer was 90%. The specificity of the method for cancer diagnosis was 100%. Two precursor lesions were present in the material: one case of atypical ductal hyperplasia, which was successfully detected, and one case of lobular neoplasia, which escaped detection. The cytological imprints were inadequate in four out of 72 cases (5.6%), but none of them were included within the malignant subgroup.
Conclusions:  Imprint cytology seems to be an important adjunctive tool in the management of patients with non-palpable mammographic solid lesions. Its very satisfactory sensitivity and optimal specificity could establish its use in general clinical practice.     

Fine needle aspiration cytology as an additional tool in the diagnosis of odontogenic keratocyst

OBJECTIVE: The aim of this study was to assess the use of fine needle aspiration cytology (FNAC) in diagnosis of odontogenic keratocyst (OKC), as well as to describe the cytological and immunohistochemical features. METHODS: Eight consecutive patients submitted to FNAC and diagnosed with OKC were included in this study. FNAC was performed using 24-gauge needles attached to a 10-ml syringe, supported by a mechanical-syringe holder to facilitate aspiration. All cases provided a liquid or viscous content for smears that were either air-dried for Diff-Quick staining or immediately fixed in 95% alcohol and stained by the Papanicolaou technique. Incisional biopsies were carried out to confirm the diagnosis. Immunohistochemical reactions against anti-pan-cytokeratin (CK), CK14 and CK19 were performed in 3 microm sections obtained from cell blocks and biopsy specimens. RESULTS: Cytologically many isolated or groups of keratinocytes with normal or ill defined nuclei were seen, besides numerous anucleated squamous cells and keratinous debris. Immunohistochemically, the keratin lamellae were positive for pan-cytokeratin and CK19, but negative for CK14. In biopsy specimens, CK14 expression was restricted to basal cells, while only the superficial cells were positive for CK19. CONCLUSIONS: In summary, FNAC is useful, reliable and safe tool for the preoperative diagnosis of OKC.