Bile duct brushings cytology – improving sensitivity of diagnosis using the ThinPrep® technique: a review of 113 cases

OBJECTIVE: Common bile duct (CBD) brushings have been recognized as a technique of moderate sensitivity and high specificity in identifying carcinoma of the ampulla and pancreatico-biliary regions. This study evaluated the increase in sensitivity of this technique using the ThinPrep technique of specimen preparation when compared with conventional cytology smears. METHODS: A total of 113 bile duct brushings were included in the study (38 conventional smears and 75 slides prepared using the ThinPrep technique). All slides were reviewed by one cytologist. Five categories of reporting were used: inadequate, negative, atypia, suspicious and malignant. RESULTS: The inadequate category of reporting disappeared in the ThinPrep group with improved specimen fixation and preparation and hence reduced artefact. Sensitivity of diagnosis of malignancy increased from 39% in conventional smears to 53% in the ThinPrep group. Specificity, positive and negative predictive values and accuracy were 100%, 100%, 60% and 68% for conventional smears and were 100%, 100%, 60% and 72%, respectively, for ThinPrep specimens. CONCLUSIONS: ThinPrep technique was associated with increased sensitivity of diagnosis, in part due to improved specimen fixation and reduced artefact. Cytology of bile duct brushings is an important diagnostic tool for sites from which it can be difficult to obtain a histology biopsy. It may therefore provide the only opportunity for tissue diagnosis of carcinoma from these sites, hence the importance of optimizing sensitivity.     

A comparative study: conventional preparation and ThinPrep® 2000 in respiratory cytology

In order to compare and contrast conventional preparation (CP) with ThinPrep 2000 (TP) in respiratory cytology, 207 samples were divided equally and processed by the two different preparation methods, generating three CP and one TP slide per sample. No lesion identified by CP was missed by TP and there were no significant differences between TP and CP in the diagnostic categories. However, two cases of squamous cell carcinoma were detected on TP which had been classified as unsatisfactory and moderate squamous dyskaryosis, respectively, on CP. ThinPrep was found to be superior to CP in many respects as it provided standardized preparations in a greater proportion of cases and problems such as cell overlapping and background debris were markedly reduced. In several instances the diagnostic accuracy in CP was compromised by smears that were either too thick, too thin, or too scanty. Cell preservation was also better on TP when compared with CP, facilitating more accurate diagnosis and significantly reducing the primary screening and reporting time, especially of sputum samples. A major advantage of TP methodology is the fact that it facilitates optimal use of skilled cytotechnologists and streamlines the workflow in the laboratory.     

Improving diagnostic yield of biliary brushings cytology for pancreatic cancer and cholangiocarcinoma

Biliary brushings are currently the best accepted method to obtain a cytological diagnosis of pancreatic cancer or cholangiocarcinoma. The technique has good specificity but poor sensitivity. Two dedicated pathologists reviewed 137 consecutive biliary brushings from 127 patients between February 1997 and February 2000. The ultimate diagnosis was determined by review of radiology, operative diagnosis and patient outcome. The sensitivity, specificity, positive predictive value and negative predictive value of the original results and the review results were calculated and compared. Additional diagnostic categories 'suspicious' and 'atypical possibly benign' were included on review. After review, the sensitivity improved from 49.4% to 89.0% and the specificity remained 100%. The use of the additional diagnostic category 'suspicious' increased the sensitivity to 90.4%, at the expense of a fall of the specificity to 66.7%. We conclude that review by two dedicated pathologists and additional diagnostic categories can improve the diagnostic accuracy of biliary brushings.     

Evaluation of thin-layer methods in urine cytology

Conventional cytospin smears prepared from urinary tract specimens were compared with two new thin layer techniques, i.e. ThinPrep and AutoCyte PREP. Cellularity, cell preservation, background features, detection rate, screening time and ease of preparation were evaluated. Thin-layer techniques when applied to urine cytology were found to improve cell yield and cell preservation, and reduce background artefact. The reporting rate for abnormal urothelial cells was comparable to conventional cytospin smears, as was screening time. Laboratory staff found the methodologies to be practicable and easily incorporated into a large routine diagnostic service. We conclude that a one-slide thin-layer urine preparation is comparable to four cytospin slides in the detection of urothelial abnormalities, and that both ThinPrep and AutoCyte PREP have comparable features.     

The role of liquid-based cytology associated with curettage in the investigation of endometrial lesions from postmenopausal women

OBJECTIVE: This study investigates the role of liquid-based cytology with ThinPrep technique, in the detection of endometrial lesions, using direct endometrial sampling from postmenopausal women with the Endogyn endometrial device. METHODS: It was performed on 491 postmenopausal women referred to our clinic for abnormal bleeding or other symptoms and/or a thickness of endometrium >5 mm on ultrasound. Endometrial sampling, dilatation and curettage (D&C) and hysterectomy were performed on all patients. For the diagnosis, the WHO classification scheme was used. RESULTS: According to our findings a sensitivity of 98.08%, specificity of 100%, positive predictive value of 100%, negative predictive value of 100% and overall accuracy of 98.98% were observed in both endometrial sampling and in D&C. CONCLUSIONS: Endometrial sampling is complementary to D&C for the diagnosis of endometrial lesions and it is necessary for it to be performed before D&C and/or hysterectomy.     

The effect of lubricant contamination on ThinPrep® (Cytyc) cervical cytology liquid-based preparations

Objectives:  To assess the extent of lubricant use by smear-takers and the effect of lubricant contamination of ThinPrep^® processed cervical cytology samples.
Methods:  All primary care smear-takers were sent a questionnaire on lubricant type and frequency of use. Fifty cervical cytology samples were then contaminated with incremental amounts of K-Y^® jelly, 50 samples contaminated with incremental amounts of Aquagel^® and ten non-contaminated vials were processed using the ThinPrep^® T2000 processor followed by Papanicolaou staining. The morphological appearances of lubricant contamination were described microscopically and formal cell counts performed on all slides.
Results:  Seventy of 94 (74.5%) primary care smear-takers indicated lubricant use of whom 9/70 (12.8%) used Aquagel^® and 61/70 (87.2%) used K-Y^® jelly. K-Y^® jelly appeared as mucoid blue deposits in the slide background whereas Aquagel^® appeared as pink stringy background material. Cell counting showed a significant difference between Aquagel^® and K-Y^® jelly contaminated slides compared to the original non-contaminated preparations for all fields and the average fields ( P  < 0.001) with a significantly higher count for the original non-contaminated slides than the lubricant contaminated groups.
Conclusion:  Lubricant contamination of ThinPrep^® cervical cytology samples may result in reduced cellularity of the subsequent slide. This study provides evidence-based data to support British Society for Clinical Cytology recommendations for no lubricant use when taking cervical samples.     

Liquid-based cytology improves productivity in cervical cytology screening.

Objectives: The ThinPrep test was introduced into our institution on a phased basis over 3 years between January 2002 and December 2004. This study set out to assess its effect on productivity (as measured by output of cases per medical scientist per day) during the changeover period. Numbers of high and low-grade lesions and of unsatisfactory slides were also monitored. Methods: The percentage conversion from conventional preparation to liquid-based cytology (LBC) and output of cases per medical scientist per day were calculated from our database at 6-month intervals. The average backlog, average number of cases received per month and percentage of unsatisfactory and abnormal cases were calculated similarly. Results: Over the study period 92 084 cases were received. The percentage of cases using ThinPrep increased: from 9% in January 2002 to 73% in December 2004. During the study there was an increase in output from 17.0 to 22.3 cases per medical scientist per day, representing a 31% improvement at 73% conversion. Numbers of unsatisfactory cases decreased substantially and the numbers of low and high-grade diagnoses were relatively constant. Conclusions: The change to ThinPrep has improved productivity and decreased the number of unsatisfactory cases. There was no adverse effect on quality during the changeover.     

Using a quality control approach to define an 'adequately cellular' liquid-based cervical cytology specimen

Objective:  To define a minimum acceptable total squamous cellularity for (ThinPrep^®) liquid-based cervical cytology (LBC) specimens using quality control techniques.
Methods:  Two hundred LBC preparations were made containing varying numbers (<200) of severely dyskaryotic squamous cells and with varying total cellularities.
Results:  Ninety-eight per cent of the LBC preparations that were missed by one or more of three cytoscreeners had fewer than 16 abnormal objects (single dyskaryotic cells or clumps of cells) and 87 dyskaryotic cells. The minimum ratio of dyskaryotic to total squamous cells that, in a preparation of 5000 squamous cells has a probability of at least 0.98 that 87 or more dyskaryotic cells will be present is 1 : 47. Twenty-three preparations diagnosed as abnormal had ratios of dyskaryotic to total squamous cells of between 1 : 2.5 and 1 : 4596. There is thus no feasible minimum acceptable squamous cellularity that will give an acceptable probability of detection of all specimen vials containing abnormal cells in the observed proportions.
Conclusions:  It is suggested that the minimum acceptable cellularity for LBC specimens is set pragmatically by the screening programme to give a feasible percentage of repeat tests.     

Use of bile cytology for early diagnosis of complications in orthotopic liver transplantation

carrasco l., sanchez-bueno f., sola j., robles r., rodriguez j. m., ramirez p., lujan j. a., acosta f. and parrilla p. (1998) Cytopathology 9, 406–414
Use of bile cytology for early diagnosis of complications in orthotopic liver transplantation
We conducted a daily analysis of bile cellularity in 25 patients undergoing 29 orthotopic liver transplants (OLT) and correlated the cytological parameters with the clinical outcome of each patient. The 16 patients without complications only showed slides with cells during the first 4–5 postoperative days. The four patients with primary non-function (PNF) of the graft had a high cell density up to the time of the retransplant, with a preponderance of polymorphonuclear (PMN) leucocytes (59.2%) and epithelial cells (29.2%). During the episodes of sepsis ( n  = 3) and rejection ( n  = 7) we noted the sudden appearance of high cellularity, almost exclusively PMN leucocytes (96.5%), and a preponderance of PMN leucocytes (84.2%) with appreciable percentages of mononuclear cells and macrophages as well as the early appearance of lymphoblasts in the rejection episodes. Our results show that bile cytology can be a useful method for diagnosing graft complications in liver transplantation.     

Thyroid fine needle aspiration cytology processed by ThinPrep: an additional slide decreased the number of inadequate results

E. D. Rossi, F. Morassi, G. Santeusanio, G. F. Zannoni and G. Fadda
Thyroid fine needle aspiration cytology processed by ThinPrep: an additional slide decreased the number of inadequate results Background: Fine needle aspiration cytology is the most accurate tool for diagnosing thyroid nodules. Its accuracy is related to the rate of inadequate samples, which can be minimized with the adoption of on‐site assessment of the adequacy of the material. The introduction of liquid‐based cytology (LBC) in the thyroid does not allow checking on the adequacy of the cellularity. The possibility of making a second LBC slide for decreasing the number of non‐diagnostic cases is studied. Methods: Out of 553 cases diagnosed in a single institution from January to March 2005, 166 consecutive cases with an LBC slide reviewed by the same pathologist were evaluated. The cases were classified in a five‐tiered category system (Thy1 to 5 according to the British Thyroid Association guidelines) and all but two (with cystic degeneration) were processed by LBC and stained with Papanicolaou stain. The above‐mentioned categories are defined as follows: Thy1 inadequate or haemorrhagic, Thy2 non‐neoplastic lesion; Thy3 follicular lesion/suspected follicular neoplasm; Thy4 suspicious for malignancy; Thy5 diagnostic of malignancy. For each case the cytological diagnosis was made on the LBC slide and the adequacy of the cellularity for a conclusive diagnosis was assessed. Results: Of the 166 cases, 39 were non‐diagnostic (Thy1—inadequate), ten presented features of cystic degeneration (Thy1—haemorrhagic), 90 were benign (Thy2), 22 were diagnosed as a follicular lesion (Thy3), one as suspicious of malignancy (Thy4) and four as papillary carcinoma (Thy5). Thirty‐nine cases had a second LBC for achieving a definitive diagnosis with eventual re‐classification. Of these cases, 23 (61.5%) led to a conclusive diagnosis (18 Thy2, five Thy3) with a 18.5% decrease of the inadequacy rate. Conclusions: The making of an additional LBC slide helps in achieving a diagnosis in cases classified as non‐diagnostic on the first standard slide (52.1% recovery rate). This procedure is particularly helpful for meeting the adequacy criteria in benign and indeterminate lesions and could also be used for refining the diagnosis of suspicious for a malignant thyroid neoplasm.     

Utility of liquid-based cytology in endometrial pathology: diagnosis of endometrial carcinoma

Objective: The purpose of this study was to examine the utility of SurePath‐liquid‐based cytology (LBC) compared to conventional cytological preparations (CCP) in the identification of endometrial carcinoma. Methods: During a 13‐month period, direct endometrial samples were collected from 120 patients using the Uterobrush. The material comprised 30 cases each of endometrial carcinoma, proliferative endometrium, secretory endometrium and atrophic endometrium. The following points were investigated:(i) the frequency of cell clumps in endometrial carcinoma; (ii) the area of cell nuclei; (iii) overlapping nuclei. Results: (i) Comparison of the frequency of cell clumps with irregular protrusion pattern and papillo‐tubular pattern showed no statistically significant difference in either type of cell clump between CCP and LBC. (ii) Comparison of the nuclear area of cells showed a sequential decrease from endometrial carcinoma to secretory endometrium, to proliferative endometrium and to atrophic endometrium, which was significant in CCP and LBC. (iii) Nuclear area was significantly lower with LBC compared with CCP in endometrial carcinoma, secretory endometrium and proliferative endometrium but not atrophic endometrium. (iv) Comparison of the degree of overlapping nuclei showed a sequential decrease from endometrial carcinoma to proliferative endometrium, to secretory endometrium and to atrophic endometrium, which was significant in both CCP and LBC. (v) Comparison of the degree of overlapping nuclei between CCP and LBC showed no significant difference for normal types of endometrium, but LBC had significantly higher values (P < 0.0001) in endometrial carcinoma than in CCP. Conclusions: The results of this study revealed that applying diagnostic criteria used in CCP to LBC was easy to achieve, because LBC had excellent cytoarchitectural preservation and cells were well presented. Although we have not examined all cytological features of malignancy and have not considered atypical hyperplasia, we believe that this method may be a useful tool in the diagnosis of endometrial cytology.     

Role of ancillary techniques in diagnosing and subclassifying non-Hodgkin''s lymphomas on fine needle aspiration cytology

Non-Hodgkin's lymphomas (NHL) are tumours of the lymphoid cells. During the process of development of lymphoid cells, neoplasia may evolve at any point. Neoplastic cells usually carry the imprint of cell of origin at the stage of origin. Various types of NHL may have similar morphology with wide variation in origin, immunophenotype and other biological features. Different ancillary laboratory techniques may help to overcome the limitations of morphology in this aspect. The commonly used ancillary techniques in lymphomas are immunocytochemistry (IC), flow cytometry, Southern blot (SB) technique, polymerase chain reaction (PCR) and fluorescent in situ hybridization (FISH). In addition, laser scanning cytometry (LSC) and DNA microarray technologies are in the research phase. Various laboratory techniques are used for immunophenotyping, demonstration of monoclonality, identification of chromosomal translocation, assessment of cell kinetics and expression of mRNA in the tumour cells. Flow cytometry helps in rapid immunophenotying of NHL and it has an added advantage over IC in recognizing the co-expression of CD markers. Fine needle aspiration cytology (FNAC) combined with flow immunophenotyping may help us to diagnose and subclassify certain NHLs, such as follicular lymphoma and mantle cell lymphoma, which were previously recognized as pure morphological entities. Loss of morphology is one of the important limitations of flow cytometry. LSC can overcome this limitation by studying morphology along with the immunophenotyping pattern of individual cells. Chromosomal changes in NHL can be identified by SB, PCR and FISH. Molecular diagnosis of NHL helps in diagnosis, subclassification, prognostic assessment and even in planning of therapy. DNA microarray is a relatively newer and promising technology. It gives information about the expression of several thousands of genes in a tumour in a single experiment. In the near future, FNAC combined with ancillary techniques may play a major role in diagnosis, subclassification and management of lymphomas.     

Evaluation of liquid-based cytology in cervical screening of high-risk populations: a split study of colposcopy and genito-urinary medicine populations

A split study evaluated the ThinPrep(R) PapTesttrade mark (TP; Cytyc Corp., Boxborough, MA) compared with current methodologies of cervical cytology in two high-risk cohorts. One thousand, three hundred cases from a colposcopy clinic and a genito-urinary medicine outpatient clinic were examined. The TP reported increased detection of all grades of dyskaryosis (mild, moderate and severe; + 4.5%) and a decrease in borderline and unsuitable cases (- 4.9%). Four cases of high-grade dyskaryosis (moderate or severe) were detected only using the TP, while an additional four cases classified as high-grade dyskaryosis with the TP were reported as borderline by our conventional methods. The split-study finding of increased sensitivity with the TP provides for improved clinical management of patients in our high-risk cohorts.     

Liquid‐based cytology: is this the way forward for cervical screening?

Liquid-based cytology (LBC) is currently being marketed as an alternative methodology to replace the conventional PAP smear in cervical cytology. A substantial body of literature exists in support of LBC, some of which is at least partially sponsored by product manufacturers. The majority of published literature in support of LBC employs Bethesda reporting terminology. In this study we have analysed published raw data and presented this in NHSCSP terminology. Claims relating to sensitivity, specificity and smear adequacy have then been considered with reference to this data. Our analysis of existing data does not support the nationwide implementation of LBC at present. Further studies are recommended in order to evaluate the place of this technology within the NHSCSP.     

Role of fine needle aspiration cytology in the diagnosis of soft tissue tumours

Fine needle aspiration cytology (FNAC) is a widely accepted safe, simple and rapid diagnostic procedure used in the examination of neoplastic and non‐neoplastic lesions of various locations. Since its introduction, FNAC has developed into an effective diagnostic tool practiced in a large majority of medical centres evaluating and treating oncological patients. The role of FNAC has been limited in the examination of primary soft tissue lesions, however, as many physicians working in this area recommended against using FNAC. An increasing use of minimally invasive diagnostic procedures in the last decade has resulted in a better acceptance of FNAC as a first‐line approach or as a complementary tool to core needle biopsy in the diagnosis of musculoskeletal lesions. This review discusses the role and value of FNAC in the evaluation and treatment of soft tissue tumours based on the experience gathered over the course of 48 years at the Sarcoma Center in Lund, Sweden. FNAC reports most often provide diagnostic information allowing the initiation of treatment or, when definitive diagnosis cannot be rendered from a cytological examination, guiding the continued diagnostic investigation. The main advantages of soft tissue FNAC are good sensitivity and specificity, low morbidity, speed of diagnosis, and low cost/benefit ratio. The most important disadvantages stem from limited experience in cytological diagnosis of soft tissue tumours and a lack of standardised and uniform reporting system for soft tissue FNAC.     

Higher diagnostic accuracy with the ThinPrep method in a simulated intraoperative environment

Objective:  To compare the accuracy of intraoperative fine needle aspiration cytology samples prepared by the ThinPrep method to conventional cytological methods. Specimen adequacy and turn around time (TAT) were also assessed.
Methods:  Fifty consecutive fresh tumours submitted for histological analysis were aspirated and each prepared as follows: (i) direct smear with H&E stain, (ii) direct smear with Pap stain, (iii) ThinPrep slide with H&E stain, and (iv) ThinPrep slide with Pap stain. The slides were randomly distributed to three cytopathologists for interpretation. The quality of the preparation, the diagnosis and the time needed for interpretation were recorded.
Results:  Accuracy was measured as the percentage of absolute agreement between the cytological and the histopathological diagnoses of the lesions. Histologically, there were 43 malignant and six benign lesions and one atypical lipoma. The TAT began when the slides/cytolyte specimens arrived at the lab and ended with the pathologist's diagnosis.
Conclusions:  In terms of accuracy and specimen adequacy, ThinPrep slides with Pap stain is the best procedure. This advantage however is offset by the longer testing time.