Comparison of ThinPrep and conventional smears in salivary gland fine-needle aspiration biopsies

Advances in diagnostic liquid-based cytology

Liquid-based cytology (LBC) has changed the landscape of gynaecological cytology. A growing demand exists for LBC in diagnostic cytology, particularly for ancillary testing, such as immunocytochemistry and molecular testing. Ancillary testing solely based on conventional preparation (CP) methods remains challenging. Recently, the increased demand for specialist testing and minimally invasive techniques, such as endoscopic ultrasonography fine-needle aspiration, to obtain cellular samples has led to an increasing demand for ancillary testing on cytology LBC supernatant, slides and cell block (CB). This facilitates the diagnosis and prognosis in cytology samples enabling personalized treatment. An understanding of the history and future prospects of LBC is crucial for its application in routine diagnostics by cytopathologists and cytotechnologists. In this review, we initiated an internet search using the keyword 'liquid-based cytology', and we conducted a literature review to discuss the usefulness of combined diagnosis of LBC and CP, immunocytochemistry and molecular testing and assessed the quality of nucleic acids in diagnostic LBC. High-quality and cell-rich diagnostic LBC surpassed the CP method alone in terms of reliability and versatility of ancillary testing in cytological diagnosis. Conclusively, diagnostic LBC lends itself to various new technologies and is expected to continue evolving with innovations in the future.

Second edition of the Milan System for Reporting Salivary Gland Cytopathology: Refining the role of salivary gland FNA

The use of standardised reporting systems for non-gynaecologic cytopathology has made enormous gains in popularity during the past decade, including for thyroid fine-needle aspiration, urine cytology, serous effusions, pancreas, lymph nodes, lung and more. In February 2018, the first edition of the Atlas of the Milan System for Reporting Salivary Gland Cytopathology (MSRSGC) was published. The MSRSGC defines six diagnostic fine-needle aspiration categories encompassing the spectrum of non-neoplastic, benign and malignant lesions of the salivary glands. The goal of the MSRSGC is to combine each diagnostic category with a defined risk of malignancy and a specific clinical and/or surgical management algorithm. Since its initial publication in 2018, more than 200 studies and commentaries have been published, confirming the role of the MSRSGC. The second edition of the MSRSGC, published in July 2023, includes refined risks of malignancy based on systematic reviews and meta-analyses, a new chapter summarising the use of salivary gland imaging, new advances in ancillary testing and updates in nomenclature.

Second edition of the Milan System for Reporting Salivary Gland Cytopathology: Refining the role of salivary gland FNA

The use of standardized reporting systems for nongynecologic cytopathology has made enormous gains in popularity during the past decade, including for thyroid fine-needle aspiration, urine cytology, serous effusions, pancreas, lymph nodes, lung, and more. In February 2018, the first edition Atlas of the Milan System for Reporting Salivary Gland Cytopathology (MSRSGC) was published. The MSRSGC defines six diagnostic fine-needle aspiration categories encompassing the spectrum of Non-Neoplastic, benign, and malignant lesions of the salivary glands. The goal of the MSRSGC is to combine each diagnostic category with a defined risk of malignancy and a specific clinical and/or surgical management algorithm. Since its initial publication in 2018, more than 200 studies and commentaries have been published confirming the role of the MSRSGC. The second edition of the MSRSGC, published in July 2023, includes refined risks of malignancy based on systematic reviews and meta-analyses, a new chapter summarizing the use of salivary gland imaging, new advances in ancillary testing, and updates in nomenclature. CONCISE SENTENCE: The second edition of the Milan System for Reporting Salivary Gland Cytopathology, published in July 2023, includes refined risks of malignancy based on systematic reviews and meta-analyses, a new chapter summarizing the use of salivary gland imaging, new advances in ancillary testing, updates in nomenclature, and a guide to the practical application of the latest ancillary markers for the diagnosis of selected salivary gland fine-needle aspiration cases.

Second edition of the Milan System for Reporting Salivary Gland Cytopathology: Refining the role of salivary gland FNA

The use of standardized reporting systems for non-gynecologic cytopathology has made enormous gains in popularity during the past decade, including for thyroid fine-needle aspiration, urine cytology, serous effusions, pancreas, lymph nodes, lung, and more. In February 2018, the first edition Atlas of the Milan System for Reporting Salivary Gland Cytopathology (MSRSGC) was published. The MSRSGC defines six diagnostic fine-needle aspiration categories encompassing the spectrum of non-neoplastic, benign, and malignant lesions of the salivary glands. The goal of the MSRSGC is to combine each diagnostic category with a defined risk of malignancy and a specific clinical and/or surgical management algorithm. Since its initial publication in 2018, more than 200 studies and commentaries have been published confirming the role of the MSRSGC. The second edition of the MSRSGC, published in July 2023, includes refined risks of malignancy based on systematic reviews and meta-analyses, a new chapter summarizing the use of salivary gland imaging, new advances in ancillary testing, and updates in nomenclature.

The risk of malignancy according to Milan reporting system of salivary gland fine-needle aspiration with Becton Dickinson SurePath liquid-based processing

BACKGROUND

Fine-needle aspiration cytology (FNAC) is a noninvasive, safe, cost-effective, diagnostic procedure for the evaluation of salivary gland lesions and the selection of patients for surgery. The aim of this study was to analyze the risk of malignancy (ROM) according to the Milan reporting system of salivary gland FNA specimens using a liquid-based cytology (LBC) technique.

METHODS

The cytological diagnosis of 459 cases between 2014 and 2017 was revised according to the Milan reporting system. The FNAC results of 129 cases with a histological diagnosis were compared with respect to the final diagnosis. The ROM for each category calculated.

RESULTS

The ROM was high in the indeterminate and malignant categories, while the ROM in the benign neoplasm category was low. Sensitivity and specificity analyzed in two different ways were 95.1% and 88.8%, 81%, and 77.7%, respectively.

CONCLUSIONS

When salivary gland lesions are evaluated together with clinical and radiological data, the LBC technique can be applied to salivary gland specimens based on the high diagnostic sensitivity and specificity in liquid-based samples reported according to the Milan system.

To Obtain More With Less: Cytologic Samples With Ancillary Molecular Techniques-The Useful Role of Liquid-Based Cytology

CONTEXT

- Fine-needle aspiration cytology has been increasingly used as the first tool in the evaluation of several diseases. Although cytology has a relevant role in the discrimination between benign and malignant lesions, conventional slides cannot lead to 100% conclusive results. It was hoped that the introduction of liquid-based cytology (LBC) would improve the efficacy of cytology through standardization, quality improvement, and the possibility of carrying out ancillary techniques on the residual stored material. In recent decades, the application of genomic alterations has been studied on cytologic samples with feasible and reliable results. The molecular analysis offers a powerful aid to define the best clinical or surgical approaches and follow-up for patients. In recent years, the application of different ancillary techniques has been carried out on conventional slides even though LBC represents a useful additional and alternative method for molecular testing.

OBJECTIVE

- To demonstrate the relevance of LBC as a valid aid to overcoming the difficulties encountered in the application of ancillary techniques on conventional slides.

DATA SOURCES

- We examined and reviewed our experience with the application of ancillary techniques on LBC performed on different body sites.

CONCLUSIONS

- We emphasize that LBC achieves significant and accurate results. It represents a valid method for cytologic evaluation and it provides highly reproducible and informative molecular yields.

Liquid-based cytology versus conventional cytology in fine-needle aspirates of salivary gland neoplasms

Background

Liquid-based cytology (LBC) is a method of retrieving and processing of cytological material for the assessment of both gynecological and nongynecological cases introduced in 1996. Mostly conventional smears (CS) are prepared in Indian scenario; however, due to increasing popularity of LBC in nongynecology specimens, LBC is also used in few centers for diagnosing salivary gland neoplasm.

Aim

The aim of this study is to compare CS and LBC in fine-needle aspiration cytology (FNAC) of the salivary gland neoplasms in terms of cytomorphological details, adequacy, ease of interpretation, pitfalls, and diagnostic efficiency.

Materials and Methods

We conducted a prospective, observational, comparative study which included 64 salivary gland neoplasms. Both CS and LBC (SurePath) were prepared as per standard protocols and examined.

Results and Conclusion

In our study, specificity and positive predictive value of both the techniques (conventional and LBC) were found to be 100%. Sensitivity of both the techniques was found to be similar (66.7%). Negative predictive value and diagnostic accuracy of conventional technique were found to be almost similar to that of LBC technique (97.6% vs. 97.2% and 97.7% vs. 97.4%). In terms of adequacy and cellularity, CSs were better than LBC. Ease of interpretation was better with CSs due to abundant chondromyxoid stroma, an important clue in the diagnosis of pleomorphic adenoma. Nuclear details and background were better in LBC as compared to CS. Hence, we conclude that in salivary gland FNAC, both CS and LBC have similar diagnostic efficiency. however, interpretation of conventional smears is easier than Liquid Based Cytology especially in cases of pleomorphic adenoma. However, some advantages of LBC in respect to conventional cytology, with better-preserved morphology obtained from LBC becomes furthermore obligatory.

Use of fluorescent in-situ hybridisation in salivary gland cytology: A powerful diagnostic tool

OBJECTIVE

Salivary gland cytology is challenging because it includes a diversity of lesions and a wide spectra of tumours. Recently, it has been reported that many types of salivary gland tumours have specific molecular diagnostic signatures that could be identified by fluorescent in-situ hybridisation (FISH). The aim of the present study was to demonstrate the feasibility and efficiency of FISH on routine cytological salivary gland smears.

METHODS

FISH was conducted on 37 cytological salivary gland smears from 34 patients. According to the cytological diagnosis suspected, MECT1/MAML2 gene fusion and rearrangements of PLAG1, MYB, or ETV6 were analysed. The presence and percentages of cells that had gene rearrangements were evaluated. Results were compared with the histological surgical samples, available from 26 patients.

RESULTS

The PLAG1 rearrangement was observed in 12/20 (60%) cases of pleomorphic adenoma. MECT1/MAML2 gene fusion was observed in 1:2 mucoepidermoid carcinomas but was not observed in five other tumours (two pleomorphic adenomas, one Warthin's tumour, one mammary analogue secretory carcinoma [MASC] and one cystic tumour). MYB rearrangement was observed in 4/4 adenoid cystic carcinomas. ETV6-gene splitting identified one MASC.

CONCLUSION

Overall, FISH had a specificity of 100% and a sensitivity of 66.7%. When FISH and cytological analyses were combined, the overall sensitivity was increased to 93.3%. It can thus be concluded that when the FISH analysis is positive, the extent of surgery could be determined with confidence pre-operatively without needing a diagnosis from a frozen section.

A diagnostic head and neck fine needle aspiration service can be provided using liquid-based cytology only

OBJECTIVE

Liquid-based cytology (LBC) has been used for non-gynaecological specimens since its introduction into routine use in cervical cytology in the mid-1990s. There are still relatively few large studies comparing performance in reporting the head and neck fine-needle aspirations (H&N FNA) processed by LBC only to conventional direct smears (CDS).

METHODS

This study compared 686 H&N FNAs processed by LBC only with 3719 CDS. All were taken under ultrasound (US) guidance by a small cohort of three consultant radiologists and reported by the author.

RESULTS

The (smaller) LBC sample was statistically representative of the larger CDS population at an alpha level of 0.05. There was no difference between CDS and LBC at a 95% confidence interval (CI) when comparing specificity and sensitivity (specificity: 94.8-96.5% versus 90.2-95.4%; sensitivity: 91.4-94.1% versus 86.8-93.4%). The inadequate rate between the two techniques was similar, 0.5-1.0% for CDS versus 0.7-2.5% for LBC. The significance difference was in the suspicious rate which was greater at 2.8-5.8% for LBC versus 1.7-2.6% for CDS. Consequently, there was a slight but non-significant difference between the two populations with respect to the overall accuracy: 93.5-95.1% for CDS versus 89.4-93.7% for LBC.

CONCLUSIONS

While there are morphological differences between LBC and CDS in H&N FNAs, once a degree of familiarity is achieved, the two techniques have equivalent sensitivity, specificity and inadequate rates.

Utility of manual liquid-based cytology and conventional smears in the evaluation of various fine-needle aspiration samples

BACKGROUND

Liquid-based cytology (LBC) preparation is a way to improve and refine the fine-needle aspiration (FNA) samples. There are a few studies comparing LBC with conventional smear (CS).

AIM

The present study was undertaken to evaluate the utility of manual LBC (MLBC) and CS preparations in various FNA samples.

MATERIALS AND METHODS

In this cross-sectional study, a total of 100 FNA samples from various anatomical sites were evaluated using MLBC and CS preparations. Cellularity, blood, informative background, monolayers, cell architecture, cytoplasmic, and nuclear preservation were compared with MLBC and CS preparations by Wilcoxon signed rank test. P < 0.05 is considered statistically significant.

RESULTS

MLBC preparations were superior to CS preparations in view of absence of blood and debris (P = 0.001), presence of monolayers (P < 0.001), and preservation of cytoplasmic (P = 0.001) and nuclear details (P = 0.001). However, no statistically significant differences were found between MLBC and CS preparations with regard to cellularity (P = 0.157), informative background (P = 0.083), and architecture (P = 0.739).

CONCLUSION

MLBC preparations in FNAC are a safe, easy, and less time-consuming procedure, and it may have promising diagnostic value in the evaluation of FNA samples from various anatomical sites. However, the use of both MLBC and CS preparations is recommended to achieve optimal diagnostic yield.

Conventional smears versus liquid-based preparations for thyroid fine-needle aspirates: a systematic review and meta-analysis

INTRODUCTION

Thyroid fine-needle aspiration has traditionally been prepared using conventional smears (CS). Liquid-based preparations (LBP) have grown in popularity and yet, there is a lack of consensus about which method is superior. This review compared CS and LBP as an intervention in the management of thyroid nodules.

MATERIALS AND METHODS

Medline, EMBASE, Scopus and ClinicalTrials.gov were searched to locate relevant studies. Observational studies comparing CS and LBP of consecutive thyroid fine-needle aspirations were included. Two reviewers independently screened, extracted, and entered data. Double data extraction included the following outcomes: (1) the proportion of inadequate smears and (2) the proportion of indeterminate smears. Studies were also assessed for risk of bias and heterogeneity.

RESULTS

From 599 unique studies, title/abstract screening identified 136 studies, and full text screening identified 13 studies. The 13 studies included 24,307 fine-needle aspirations from 19,433 patients and had high clinical, methodological, and statistical heterogeneity with low risk of bias. For CS and LBP, a meta-analysis of 12 studies showed no difference in the proportion of inadequate smears (risk difference: -0.00; 95% confidence interval [CI]: -0.04-0.04); 13 studies showed no difference in the proportion of indeterminate smears (risk difference: -0.02; 95% CI: -0.05-0.01). Sensitivity analysis of studies with low risk of bias had similar results.

CONCLUSIONS

There is no difference between CS and LBP in the proportion of inadequate and indeterminate smears. Recommendations of one method over the other should be based on cost, feasibility, and accuracy, all of which require further study.

Efficacy of liquid-based cytology versus conventional smears in FNA samples

BACKGROUND

Liquid-based cytology (LBC) is fast becoming a useful method in evaluating both gynecological and non-gynecological preparations, including fine needle aspiration (FNA) cytology. Even distribution of cells, decreasing obscuring background elements like blood and mucus, well preserved nuclear and cytoplasmic details and rapid fixation helps in better visualization of cells.

AIM

This study was conducted to asses the diagnostic accuracy of liquid-based cytology versus conventional smears in fine needle aspiration samples.

STUDY DESIGN

In this prospective study, we had 110 cases, including 30 cases of breast, 40 of lymph node, 10 of salivary glands, 18 of thyroid and 12 of bone and soft tissue. In each case, two passes were performed. The first pass was for conventional preparation (CP) and the second pass yielded material for thin-prep (TP) preparation. Both CP and TP smears were compared for cellularity, background blood and necrotic cell debris, cell architecture, informative background, presence of a monolayer of cells and nuclear and cytoplasmic details by a semiquantitative scoring system. Wilcoxon's signed rank test on an SPSS program was used for statistical analysis.

RESULTS

Diagnostic accuracy was better in LBC smears compared with CP smears due to lack of background debris and better cell morphology, which was performed according to Wilcoxon's signed rank test, yielding a P-value of <0.001. However, in some cases, because of a decrease in cell size, clustering and altered background in LBC, a support of CP was essential.

CONCLUSION

LBC performed on FNA samples can be a simple and valuable technique. Only in few selected cases, where background factor is an essential diagnostic clue, a combination of both CP and TP is necessary.

How do liquid-based preparations of thyroid fine-needle aspiration compare with conventional smears? An analysis of 5475 specimens

BACKGROUND

Fine-needle aspiration (FNA) plays a pivotal role in the initial evaluation of patients with thyroid nodules. Traditionally, aspirated material is expelled directly onto the microscope slide to make a conventional smear (CS). Recently, liquid-based preparations (LBP) have gained in popularity. This study compares the accuracy of these two preparation techniques in diagnosing thyroid nodules.

METHODS

A clinical database containing 5475 thyroid cytology consults from 2009 to 2013 was queried to identify 5169 CS and 306 LBP cases. Cytological diagnostic frequency rendered before and after second review were compared between LBP and CS. Correlation with the histology diagnosis was also calculated for each preparatory technique.

RESULTS

Age, sex, and nodule size were comparable between patients who had FNA processed by LBP and CS. More LBP cases than CS cases were inadequate (17% vs. 10%; p<0.001). LBP cases had fewer benign diagnoses (39% vs. 47%; p=0.003) and tended to have more malignant diagnoses (16% vs. 12%; p=0.09) when compared to CS. Indeterminate and suspicious categories were comparable between LBP and CS. Correlation with histology was also comparable between both techniques.

CONCLUSION

LBP was associated with a significantly higher proportion of inadequate and a lower proportion of benign diagnoses. Thus, universal adoption of LBP may introduce more inadequate samples. Future investigations should explore the lack of on-site evaluation with LBP as a potential source for the high inadequate rate.

The utility of liquid-based cytology in salivary gland fine-needle aspirates: experience of an academic institution

OBJECTIVE

To review the morphological features of salivary gland fine-needle aspirates (FNA) on ThinPrep® (TP) preparations. Emphasis is placed on the commonalities and specific differences between TP and conventional smear (CS) preparations.

STUDY DESIGN

The cytology and surgical pathology archives were searched for 'salivary' or 'parotid' at our institution from 2003 to 2013 for cases processed by TP and with a range of specified diagnoses and surgical follow-up. These cases were reviewed by the authors. A review of the known literature was also performed.

RESULTS

Morphological features and artifacts were noted for the most common salivary gland lesions. General features noted in the literature were identified, along with novel features identified on our review of cases. Emphasis was placed on cellular alterations, extracellular differences and architectural changes.

CONCLUSIONS

The multitude of both benign and malignant lesions coupled with the unique artifacts encountered on TP makes salivary gland FNAs difficult for most practicing pathologists and cytopathologists. For this reason, many laboratories have been reluctant to implement TP preparations for these lesions. With knowledge of the specific artifacts and differences on TP compared to CS, TP can be used with confidence without a compromise in diagnostic accuracy for adequately cellular samples.

Introduction and utility of liquid-based cytology on aspiration biopsy of peripheral nodular lesions of the lung

In the present study, aspiration biopsy cytology (ABC) was used for the diagnosis of peripheral nodular lesions in the lung (PNLL), and liquid-based cytology (LBC) was carried out on the material collected to evaluate it in comparison with the conventional method (CM). The subjects comprised 130 cases that underwent computed tomography (CT)-guided ABC for PNLL. A total of 73 cases received a tumor resection, with a diagnosis based on the pathology, while 57 cases were followed up, as the tumor showed no change on the radiological examinations. Biopsy samples from these patients and lavage fluid from the aspiration needles were used for analysis. Cellular material was obtained by centrifugation of the lavage fluid, and samples were prepared by two methods, direct smearing and LBC according to the ThinPrep method. The samples were categorized into three diagnoses: i) Benign, ii) suspicion of malignancy and iii) malignant. Appropriate samples were collected in 72% of cases by LBC, but only in 36% of cases by the CM. There was no marked difference in cellular images between the two methods, with the exception of a few specific cases. LBC on its own provided sensitivity at 68%, specificity at 61% and accuracy at 65%, while a combination of LBC and biopsy markedly improved these figures to 94, 81 and 84%, respectively. The introduction of LBC is considered useful for the cytopathological diagnosis of PNLL by CT-guided ABC. LBC enables the examination of appropriate samples rich in cellular components and supports a biopsy-based diagnosis. A combination of these two methods provides even higher diagnostic accuracy, and LBC is considered an excellent method to evaluate these pathological samples.

Overview of nongynecological samples prepared with liquid-based cytology medium

OBJECTIVE

Liquid-based cytology of nongynecological specimens is commonly used in cytology laboratories throughout the world and various processing methods, such as ThinPrep and SurePath, have been reported. The cytological features and performance of liquid-based cytology for various cytology specimens, including body cavity fluids, urine, brushing specimens and fine-needle aspiration of various lesions, were reviewed and compared with the experience of our laboratory and the literature published in PubMed.

STUDY DESIGN

The parameters for the evaluation of liquid-based cytology and conventional smears were described in the various types of specimens. Criteria for the interpretation of nongynecological liquid-based cytology were highlighted to show differences in cell morphology, background and artifacts.

RESULTS

The interpretation requires familiarity with the appearance of liquid-based cytology in the various types of preparations to avoid misdiagnosis.

CONCLUSIONS

Cell blocks can be prepared with specimens preserved in a liquid-based cytology medium and immunocytochemical stains and molecular testing can be successfully performed. These are important adjuncts in order to reach a definitive diagnosis.

Value of fine-needle aspiration biopsy in initial evaluation of floor of the mouth masses: report of a case of low-grade mucoepidermoid carcinoma

Low-grade mucoepidermoid carcinoma (LG MEC) is a rare tumor which can occur in the minor salivary glands as intraoral lesion, more frequently in the palate and very rarely in the floor of the mouth. Traditionally, the diagnosis has been made on surgical resection specimens only. There is new growing evidence that these lesions can be accurately diagnosed by a fine-needle aspiration (FNA) biopsy procedure. In this article, we report a case of LG MEC of the floor of mouth diagnosed by FNA and confirmed by subsequent surgical resection. We also provide clues for high index of suspicion for these rare lesions, both clinically and morphologically.

Comparison of Thin-Prep and cell block preparation for the evaluation of Thyroid epithelial lesions on fine needle aspiration biopsy

Background

The objective of this study was to compare the utility of Thin-Prep (TP) cytologic preparation with that of Cell Block (CB) preparation in the diagnosis of thyroid lesions, mainly follicular epithelial lesions, by fine needle aspiration biopsy (FNAB). Feasibility of using the TP slides for immunocytochemical stains is also discussed.

Methods

A total of 126 consecutive cases of thyroid FNAB with TP slides and 128 consecutive cases of thyroid FNAB with CB slides were reviewed blindly by two cytopathologists. The presence of colloid, follicular cells, macrophages and lymphocytes/plasma cells were recorded and scored 0–4 on each case based on TP or CB slide review. The cytologic diagnoses were grouped as follows: cyst, colloid nodule, colloid nodule with cystic change, chronic thyroiditis, atypical/neoplastic and non-diagnostic.

Results

The TP slides had higher diagnostic rate than CB slides. The diagnostic yield was 68% of the TP slides whereas only 24% of the CB slides were diagnostic. Also, only 4 atypical/neoplastic lesions were diagnosed on the TP slides and the corresponding direct smears, while 5 cases of atypical/neoplastic lesions were diagnosed on the smears but could not be diagnosed on the corresponding CB slides. Additionally, the TP slides revealed cytologic features that were not observed on the direct traditional smears of the same case.

Conclusion

In thyroid FNAB cases, TP slide preparation is superior to CB slide preparation and is more likely to have greater cellularity for diagnosis and detect atypical/neoplastic thyroid lesions, particularly those of follicular cell origin. Furthermore, TP slides appear to detect helpful diagnostic cytologic features and should be considered complementary to, rather than replacing, direct smears.

Non-gynecologic cytology on liquid-based preparations: A morphologic review of facts and artifacts

Liquid-based preparations (LBP) are increasingly being used both for gynecologic (gyn) and non-gynecologic (non-gyn) cytology including fine needle aspirations (FNA). The two FDA-approved LBP currently in use include ThinPrep (TP), (Cytyc Corp, Marlborough, MA) and SurePath (SP), (TriPath Imaging Inc., Burlington, NC). TP was approved for cervico-vaginal (Pap test) cytology in 1996 and SP in 1999 and both have since also been used for non-gyn cytology. In the LBP, instead of being smeared, cells are rinsed into a liquid preservative collection medium and processed on automated devices. Even after a decade of use, the morphological interpretation of LBP remains a diagnostic challenge because of somewhat altered morphology and artifacts or facts resulting from the fixation and processing techniques. These changes include cleaner background with altered or reduced background and extracellular elements; architectural changes such as smaller cell clusters and sheets, breakage of papillae; altered cell distribution with more dyscohesion and changes in cellular morphology with enhanced nuclear features, smaller cell size and slightly more three-dimensional (3-D) clusters. Herein, we review the published literature on morphological aspects of LBP for non-gyn cytology.