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

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.

Utility of SHOX2 and RASSF1A gene methylation detection on the residual cytology material from endobronchial ultrasound-guided transbronchial needle aspiration

Objective

This study aims to assess the effectiveness of Short Stature Homeobox 2 (SHOX2) and RAS Association Domain Family 1 Isoform A (RASSF1A) gene methylation detection in residual liquid-based cytology (LBC) materials from Endobronchial Ultrasound-Guided Transbronchial Needle Aspiration (EBUS-TBNA) and investigate the diagnostic accuracy of a comprehensive diagnostic approach.

Material and Methods

Between June 2022 and May 2023, a total of 110 cases that underwent EBUS-TBNA were enrolled in the study. SHOX2 and RASSF1A genes methylation detection using the residual cytological material, LBC, and cell block (CB) were conducted for each EBUS-TBNA case. The sensitivity and specificity of cytology, CB histopathology, SHOX2, and RASSF1A methylation in diagnosing EBUS-TBNA samples were determined based on follow-up data.

Results

Among the 72 cases confirmed as pulmonary carcinomas, the methylation test yielded positive results in 24 adenocarcinoma cases, 10 squamous cell carcinoma cases, and 14 small cell carcinoma cases. The sensitivity of the comprehensive diagnosis (combining LBC, CB, and methylation detection) in distinguishing metastatic pulmonary epithelial malignancies in mediastinal and hilar lymph nodes or masses from benign lesions was higher (97.22%, 70/72) than that of morphological diagnosis alone (LBC and CB) (88.89%, 64/72; P < 0.05).

Conclusion

SHOX2 and RASSF1A methylation detection demonstrates a high sensitivity and negative predictive value in the identification of pulmonary epithelial malignancies and holds promise as a valuable ancillary approach to enhance morphological diagnosis of EBUS-TBNA.

Comparison of non-invasive diagnostic modalities for ocular surface squamous neoplasia at a tertiary hospital, South Africa

AIMS

The aim of the study is to assess non-invasive diagnostic modalities for ocular surface squamous neoplasia (OSSN) when compared to histology.

METHODS

A prospective case-control study was conducted of patients presenting with conjunctival masses at a tertiary eye hospital in Johannesburg, South Africa. Patients completed an interview and had three non-invasive diagnostic tests: optical coherence tomography, impression cytology and methylene blue stain. A biopsy with histology was performed as the gold standard to confirm the diagnosis.

RESULTS

One hundred and eighty-two conjunctival masses of 175 patients were evaluated. There were 135 lesions identified as OSSN on biopsy and 47 lesions were benign on histology. Optical coherence tomography had a sensitivity and specificity of 87.2% (95% CI: 80.0-92.5) and 75.6% (95% CI: 60.5-87.1), respectively, when an epithelial thickness cutoff of 140 um was used. Shadowing was found in 46% of cases due to leukoplakia or increased thickness of the mass. Cytology had a sensitivity of 72.4% (95% CI: 62.5-81.0) and a specificity of 74.3% (95% CI: 56.7-87.5). Twenty-seven per cent of cytology specimens were excluded from analysis due to inadequate cellularity. Methylene blue had a high sensitivity of 91.9% (95% CI: 85.9-95.9), but low specificity of 55.3% (95% CI: 40.1-69.8).

CONCLUSION

Optical coherence tomography had a high sensitivity and specificity as a non-invasive test and liquid-based cytology performed well but had a lower sensitivity and specificity than with optical coherence tomography. Methylene blue performed well as a screening test, with a high sensitivity but low specificity.

Diagnostic Value of Preparing Additional Liquid-Based Cytology Slides and Cell Blocks from Residue Material in Thyroid fine Needle Aspiration

Background and Aims

After liquid-based cytology (LBC) technique developed for cervical cytology, it has been used for nongynecological samples and has been very successful. It offers having extra slides of the samples for further examination and ancillary tests. Moreover, cell blocks can be formed from the residue material. The study aimed to evaluate the importance of preparing a second LBC slide or a cell block from the residue material of thyroid fine needle aspiration (FNA) samples to reach a definitive diagnosis in cases diagnosed as nondiagnostic (ND) after the first slide.

Material and Methods

Seventy five cases diagnosed as ND after the first slide were included in study. For 50 cases, the second LBC slides were prepared (LBC group); for 25 cases, cell block was performed from residue material (CB group). Two groups were compared in terms of reaching a definitive diagnosis.

Results

At the end of secondary procedures, a definitive diagnosis was reached in a total of 24 cases (32%). Twenty of 50 cases (40%) in LBC group reached a definitive diagnosis while four cases (16%) in the CB group reached a definitive diagnosis. Achieving a definitive diagnosis was found statistically higher in the LBC group in which the second slide was formed compared to the CB group (P =0.036).

Conclusion

Preparing a second slide with LBC method is more purposive than preparing a cell block from the residue material of thyroid FNA samples. Reducing the percentage of ND cases will protect patients from complications and morbidity that may arise from repeated FNA.

Lymphoproliferative disorder involving body fluid: diagnostic approaches and roles of ancillary studies

Lymphocyte-rich effusions represent benign reactive process or neoplastic condition. Involvement of lymphoproliferative disease in body cavity is not uncommon, and it often causes diagnostic challenge. In this review, we suggest a practical diagnostic approach toward lymphocyte-rich effusions, share representative cases, and discuss the utility of ancillary tests. Cytomorphologic features favoring neoplastic condition include high cellularity, cellular atypia/pleomorphism, monomorphic cell population, and frequent apoptosis, whereas lack of atypia, polymorphic cell population, and predominance of small T cells usually represent benign reactive process. Involvement of non-hematolymphoid malignant cells in body fluid should be ruled out first, followed by categorization of the samples into either small/medium-sized cell dominant or large-sized cell dominant fluid. Small/medium-sized cell dominant effusions require ancillary tests when either cellular atypia or history/clinical suspicion of lymphoproliferative disease is present. Large-sized cell dominant effusions usually suggest neoplastic condition, however, in the settings of initial presentation or low overall cellularity, ancillary studies are helpful for more clarification. Ancillary tests including immunocytochemistry, in situ hybridization, clonality test, and next-generation sequencing can be performed using cytologic preparations. Throughout the diagnostic process, proper review of clinical history, cytomorphologic examination, and application of adequate ancillary tests are key elements for successful diagnosis.

Diagnostic accuracy of Thinprep® in cervical lymph node aspiration: Assessment according to the Sydney system

BACKGROUND

Fine-needle aspiration cytology (FNAC) is a reliable technique that has been used for many years in lymphadenopathy diagnosis. Although conventional smear is the standard approach in FNAC, liquid-based cytology (LBC) is accepted as an alternative method. Reporting standardization is a significant gap in fine-needle aspiration cytology, leading to failure in pathologist-clinician dialog and interobserver variability. In 2020, an expert panel proposed the Sydney system for classifying and reporting lymph node aspiration cytology. This study aimed to evaluate the diagnostic accuracy of LBC in lymph node aspiration cytology under the guidance of the Sydney system.

METHODS

Five hundred-four LBC samples were reevaluated and classified according to the Sydney system. Of these, n = 24 were categorized as L1-inadequate/non-diagnostic, n = 283 as L2-benign, n = 36 as L3- atypical cells of undetermined significance/atypical lymphoid cells of uncertain significance (AUS/ALUS), n = 48 as L4-suspicious, and n = 113 as L5-malignant. Four hundred-one samples were histopathologically confirmed. The diagnostic accuracy of LBC and the risk of malignancy for each Sydney category were calculated.

RESULTS

The results were as follows: sensitivity 98.97%; specificity 98.60%; positive predictive value 94.80%; negative predictive value 99.29%; and overall diagnostic accuracy 98.75%. The ROM was 16.6% for L1, 0.7% for L2, 88.8% for L3, and 100% for L4 and L5.

CONCLUSION

LBC is suitable for use in lymph node aspiration under the guidance of the Sydney system and has high diagnostic accuracy. Future comprehensive studies will increase the applicability of the Sydney system and minimize interobserver variability.

Diagnostic challenges in the gray-zone lesions of fine-needle aspiration cytology

Fine-needle aspiration cytology (FNAC) is an excellent technique for rapid diagnosis due to its speed, accuracy, and cost-effectiveness. However, there are many gray-zone areas in cytology that needs attention. These lesions in the aspiration cytology can be overcome by applying the selective use of the series of tests. This review discusses the diagnostic challenges in the gray-zone areas in FNAC. It emphasizes the use of selective ancillary techniques to solve the problems in this area.

Diagnostic value of liquid-based cytology test in intrathoracic lymph nodes and lung lesions sampled by endobronchial ultrasonography-transbronchial needle aspiration

BACKGROUNDS

Liquid-based cytology (LBC) has begun to be used in non-gynecological samples such as endobronchial ultrasound-guided transbronchial needle aspiration (EBUS-TBNA). This study aims to investigate the diagnostic value of LBC in intrathoracic lymph nodes and lung lesions sampled with EBUS-TBNA.

METHODS

In total, 174 cases that underwent EBUS-TBNA between July 2020 and February 2021 were included (75 and 99 cases were prepared using conventional and LBC methods, respectively). The two groups were compared in terms of diagnostic categories, number of slides, cell blocks, slides per location, locations sampled, immunohistochemical studies, sensitivity, specificity, and diagnostic accuracy.

RESULTS

The percentages of malignant, suspicious for malignancy, benign, and non-diagnostic (ND) cases were 51.8%, 1.1%, 39.6%, and 7.5%, respectively. The LBC and conventional group (CG) had similar rates in the diagnostic categories, except for ND (3.0% and 13.3%, respectively). The sensitivity of LBC and CG were 90.4% and 85.7%, respectively. There were no differences in the specificity and diagnostic accuracy between groups. There was a statistically significant difference between groups in terms of the number of slides, number of slides per location, number of cell blocks, and locations sampled (p < .001, p < .001, p < .05, p < .05).

CONCLUSION

The LBC technique can be used for samples taken with EBUS-TBNA. Rapid fixation and the absence of artificial problems greatly reduce the rate of ND samples in LBC slides. Other important advantages are a lower number of slides to examine and a greater number of cell blocks.

Molecular Testing on Cytology for Gene Fusion Detection

Cytology samples are suitable for the study of genotypic and phenotypic changes observed in different tumors. Being a minimally invasive technique, cytology sampling has been used as an acceptable alternative to track the alterations associated with tumor progression. Although the detection of gene mutations is well-established on cytology, in the last few years, gene fusion detections are becoming mandatory, especially in some tumor types such as lung cancer. Different technologies are available such as immunocytochemistry, fluorescence in situ hybridization, reverse transcription-polymerase chain reaction, and massive parallel sequencing approaches. Considering that many new drugs targeted fusion proteins, cytological samples can be of use to detect gene fusions in solid and lymphoproliferative tumor patients. In this article, we revised the use of several techniques utilized to check gene fusions in cytological material.

Cytohistological Correlation in Pleural Effusions Based on the International System for Reporting Serous Fluid Cytopathology

The International System for Reporting Serous Fluid Cytology (TIS) was recently developed. Given its novelty, most studies looking into the risk of malignancy (ROM) of serous effusion diagnostic categories were published before the development of TIS. We searched the database of our department for pleural effusions diagnosed in the last five years, excluding those without a corresponding pleural biopsy. Cases were reviewed and reclassified according to the TIS. A cytohistological correlation was performed. In total, 350 pleural effusion specimens with one or more corresponding pleural biopsies were included. After reclassification, 5 (1.43%) were nondiagnostic (ND), 253 (72.29%) were negative for malignancy (NFM), 7 (2.00%) had atypia of unknown significance (AUS), 14 (4.00%) were suspicious for malignancy (SFM), and 71 (20.57%) were malignant (MAL). Calculated ROM was 40% for ND, 20.16% for NFM, 42.86% for AUS, 78.57% for SFM, and 100% for MAL. Effusion cytology sensitivity and specificity were 60.29% and 98.56%, respectively. This is the first publication looking into the cytohistological correlation of a retrospective cohort of pleural effusions based on the TIS. We add to the body of data regarding the ROM for TIS categories, highlighting areas of potential future research.

Next Generation Sequencing in Cytopathology: Focus on Non-Small Cell Lung Cancer

Molecular cytopathology is a rapidly evolving field embracing both conventional microscopy and molecular pathology. Its growing popularity stems from the fact that in many types of advanced cancers, including non small cell lung cancer (NSCLC), cytological samples often constitute the only available specimens for morphomolecular analysis. Indeed, non formalin fixed and paraffin embedded (FFPE) cytological samples feature a higher quality of extracted nucleic acids than histological specimens. However, because of the growing complexity of molecular testing, several efforts should be made to validate the analytical performance of the wide array of currently available molecular technologies, including next generation sequencing (NGS). This technology has the terrific advantage of allowing simultaneous detection of scores of predictive biomarkers even in low-input DNA/RNA specimens. Here, we briefly review the role of the modern cytopathologist in the morphomolecular diagnosing of advanced stage NSCLC and the adoption of NGS in conventional cytopreparations (cell blocks, direct smears, and liquid-based cytology) and supernatants.

Oncogenic gene transcripts detection by FISH on liquid-based cytology slides of 338 advanced lung cancer patients

INTRODUCTION

Oncogenic gene transcripts in advanced lung cancer are a strong indication for targeted therapy. Cytology specimens are often the only materials available for oncogenic fusion analysis. This prospective study is to evaluate the feasibility of anaplastic lymphoma kinase (ALK) gene rearrangements, ROS oncogene 1 (ROS-1), and c-mesenchymal-epidermal transformation (c-MET) detected by fluorescence in situ hybridization (FISH) using liquid-based cytology (LBC) slides.

MATERIALS AND METHODS

Consecutive cytology specimens including fine-needle aspiration biopsy (FNAB) and serous effusions from 338 advanced lung cancer patients were collected between March 1, 2015, and July 6, 2016. The correlation between ALK, ROS-1, c-MET, and other common driver gene abnormalities and the therapeutic response to crizotinib in ALK-positive patients were also evaluated.

RESULTS

ALK fusion transcripts were detected in 31 of 338 patients (9.17%). Twenty-two of the 31 ALK-positive patients were treated with crizotinib at our institution (2 were lost to follow-up), and the overall response rate was 75.0 % (15 of 20); disease control rate was 90.0% (18 of 20). FISH analyses for ROS-1 and c-MET were performed on 75 and 73 patients, respectively, and showed 3 patients positive for ROS-1 and 3 positive for c-MET. These positive cases were all ALK-negative.

CONCLUSION

For patients with advanced lung cancer, LBC slides are suitable for detecting oncogenic gene transcripts, and the results can provide a reliable guideline for targeted therapy.

Diagnosis and staging of ocular surface squamous neoplasia

Background: Ocular surface squamous neoplasia (OSSN) is the most common ocular tumour. The diagnosis of OSSN is based on clinical suspicion and confirmed by various diagnostic modalities, of which histology is the gold standard. With the move to less invasive management options such as topical chemo- or immunotherapy, less invasive diagnostic options have come to the fore.Aim: The purpose of this article was to review the current staging and diagnostic modalities for OSSN with a focus on less invasive modalities.Method: A literature review was performed for publications on ocular surface neoplasia and diagnostic modalities.Results: Histology is the gold standard for diagnosing OSSN. Cytology has been shown to be a simple, repeatable and minimally invasive diagnostic modality, which also allows for additional testing such as polymerase chain reaction. Anterior segment optical coherence tomography provides a non-contact method of evaluating the ocular surface, with OSSN showing a thickened hyper-reflective epithelium, abrupt transition zone and demarcation line. Vital dyes are used less commonly with high sensitivity, but lower specificity for OSSN. Finally, confocal microscopy provides en-face images of the ocular surface, with OSSN showing a classic ‘starry night’ appearance.Conclusion: Histology remains the gold standard for diagnosis; however, with the increasing use of topical therapy for OSSN, there has been an increase in the uptake of less invasive diagnostic modalities.

Cytohistological correlation in serous effusions using the newly proposed International System for Reporting Serous Fluid Cytopathology: Experience of an oncological center

BACKGROUND

Cytological analysis is part of the initial etiological evaluation of serous effusions. The newly proposed International System for Reporting Serous Fluid Cytopathology (ISRSFC) aims to standardize reporting.

METHODS

All pleural and peritoneal effusion samples admitted for cytological analysis at our institution between 2012 and 2016, and pericardial effusion samples admitted between 2008 and 2018, were reviewed and reclassified according to the ISRSFC. Risk of malignancy (ROM) and performance parameters were calculated.

RESULTS

1496 pleural effusion samples were reclassified: 12(0.8%) non-diagnostic (ND), 944(63.1%) negative for malignancy (NFM), 9(0.6%) atypia of undetermined significance (AUS), 54(3.6%) suspicious of malignancy (SFM) and 477(31.9%) malignant (M). 64 pericardial effusion samples were reclassified: 23(35.9%) NFM, 1(1.6%) AUS, 4(6.3%) SFM and 36(56.2%) M. 763 peritoneal effusion samples were reclassified: 5(0.7%) ND, 457(59.9%) NFM, 12(1.6%) AUS, 37(4.8%) SFM and 252(33%) M. The ROM was, respectively, for each of the aforementioned categories, 57.1%, 23.9%, 50%, 76.2%, 100% in pleural effusions, 100%, 26.3%, 62.5%, 91.7%, 100% in peritoneal effusions and 0% for NFM, 0% for AUS and 100% for M in pericardial effusions. Sensitivity, specificity, positive predictive value, negative predictive value and diagnostic accuracy were, respectively, 61.6%, 100%, 100%, 73.3%, 81.3% for pleural, 100%, 100%, 100%, 100%, 100% for pericardial and 61.2%, 100%, 100%, 70%, 79.7% for peritoneal effusion samples.

CONCLUSION

Serous effusion cytology has a high specificity and positive predictive value and a modest sensitivity and negative predictive value, supporting its role in confirming the diagnosis of malignancy. The ISRSFC will increase standardization and reproducibility in reporting, leading to improved clinical decision-making.

EBUS-FNA cytologic-histologic correlation of PD-L1 immunohistochemistry in non-small cell lung cancer

INTRODUCTION

Immune checkpoint pathway markers induce immune tolerance to non-small cell lung cancer (NSCLC). Therapeutic antibodies targeting the programmed cell death 1 (PD-1)/programmed cell death ligand 1 (PD-L1) pathway have demonstrated efficacy in tumors expressing relatively high PD-L1 levels. Minimally invasive endobronchial ultrasound-guided fine needle aspiration allows patients with inoperable tumors or comorbidities to attain a confirmatory diagnosis. The aims of the present study were to determine whether PD-L1 testing is equivalent to cytology and biopsy or resection specimens at different tumor proportion score cutoffs and for different NSCLC subtypes.

MATERIALS AND METHODS

Data were retrospectively collected for patients with paired NSCLC cytology and surgical resection specimens from May 4, 2007 to May 4, 2017. The Food and Drug Administration-approved Dako PD-L1 immunohistochemistry 22C3 pharmDx kit was used to measure PD-L1 on paired cytology cell block and biopsy or resection specimens, and the PD-L1 tumor proportion scores were recorded. Statistical analysis of categorical and continuous variables was performed using SAS, version 9.4.

RESULTS

A total of 53 paired cytology and resection samples (27 adenocarcinoma, 25 squamous cell carcinoma, and 1 unclassified) were analyzed. Supposing the resection specimen to reflect the true PD-L1 expression, the sensitivity, specificity, positive predictive value, negative predictive value, and overall agreement for the cytology method was 73.3%, 65.2%, 73.3%, 65.2%, and 69.8%, respectively. For high PD-L1 expression (≥50%), the cytology method demonstrated an overall agreement of 79.2%. The overall agreement between methods was 81.5% and 76% for cases of adenocarcinoma and squamous cell carcinoma, respectively.

CONCLUSIONS

NSCLC cytology samples from endobronchial ultrasound-guided fine needle aspiration are suitable for PD-L1 testing, especially using a high PD-L1 expression cutoff of ≥50% and for adenocarcinoma.

Comparison of the SuperARMS and ARMS for detecting EGFR mutations in liquid-based cytology specimens from NSCLC patients

BACKGROUND

Non-surgical cytological specimens are adequate not only for accurate histological subtyping but also for molecular profiling. A modified amplification refractory mutation system polymerase chain reaction (ARMS PCR), known as SuperARMS PCR, was improved by optimizing the primers designation, which provides a higher sensitivity and specificity approach for free plasma DNA detection. It is unclear whether SuperARMS PCR detects epidermal growth factor receptor (EGFR) mutations in cytology samples. The aim of this study was to compare the EGFR mutations detected by ARMS PCR and SuperARMS PCR in cytology samples derived from advanced non-small cell lung cancer (NSCLC) patients.

METHODS

From March 2016 to March 2018, a total of 234 cytological samples were obtained from primary or metastatic lesions of NSCLC, including 144 fine-needle aspirations (FNAs), 36 endobroncheal ultrasonography (EBUS) FNAs, 36 transbronchial needle aspirations (TBNAs) and 18 pleural effusion (PLEs). EGFR mutations were simultaneously detected using an ADx-ARMS EGFR kit (Amoy Diagnostics CO., ltd., Xiamen, China) and an ADx-SuperARMS EGFR kit (Amoy Diagnostics CO., ltd., Xiamen, China). Digital droplet PCR (ddPCR) and next-generation sequencing (NGS) were further used to verify the EGFR mutant inconsistent samples.

RESULTS

All of the 234 patients with advanced or recurrent NSCLC were diagnosed and assessed by two cytopathologists, and their EGFR mutation statuses were successfully detected by ARMS and SuperARMS. Importantly, the SuperARMS and ARMS methods showed a highly concordant result of 94.0% (220/234) (95%CI: 85.0, 95.0%). The positive rate of the SuperARMS was higher than the ARMS in the cytology samples for EGFR detection (46.2% vs. 40.2%). The specific EGFR mutation sites in 16 samples (6.8%) were not completely consistent between the SuperARMS and ARMS. A total of 14 patients showed EGFR mutations when detected by SuperARMS, but by ARMS there were EGFR wild-type. Two patients were detected as having one more EGFR mutation site by SuperARMS than by ARMS. ddPCR and NGS were used to further confirm the EGFR mutations in these inconsistent samples. Eight samples had the same mutation results as the SuperARMS, and 6 samples were not verified because the remaining DNA was insufficient. A total of 78 EGFR mutation patients received Tyrosine Kinase Inhibitor (TKI) treatment. The overall objective response rate (ORR) was 88.5% (69/78) for EGFR TKI treatment.

CONCLUSION

SuperARMS showed a high sensitivity and specificity for EGFR detection and thus, is expected to become a routine test in the clinic to be used as a widely available, easy-to-operate and sensitive method for EGFR mutation detection in liquid-based cytology samples.

Are we ready to develop a tiered scheme for the effusion cytology? A comprehensive review and analysis of the literature

BACKGROUND

Cytology is widely utilized in the initial evaluation of fluid accumulation in the body cavities. The aim of this study was to determine the accuracy of cytology in distinguishing between benign and malignant (MAL) effusions.

METHODS

A comprehensive and systematic review of the literature was conducted to evaluate the accuracy of serous effusion cytology (SEC) against tissue biopsy/resection histology, imaging, or clinical follow-up as the reference test. Risk of publication bias and level of heterogeneity in the included studies was assessed. Meta-regression was performed to assess the effect of various variables on the accuracy of SEC.

RESULTS

Eighty studies met the inclusion criteria for meta-analysis comprising of 34 941 samples; of which 52 (0.2%), 22 202 (72.7%), 194 (0.6%), 711 (2.3%), and 6507 (21.3%) could be reclassified as nondiagnostic (ND), negative for malignancy (NFM), atypical (atypia of uncertain significance-AUS), suspicious for malignancy (SFM), and malignant (MAL), respectively. On follow-up, the mean risk of malignancy for ND, NFM, AUS, SFM, MAL was 17.4%, 20.7%, 65.9%, 81.8%, and 98.9%, respectively. A total of 73 studies were included in estimating the diagnostic accuracy of SEC. The bivariate mixed-effect model estimated the SEC sensitivity, specificity, diagnostic odds ratio, positive likelihood ratio, and negative likelihood ratio as 73.1%, 99.9%, 7850.6%, 2112.2%, and 0.27%, respectively.

CONCLUSION

Serous effusion cytology shows high specificity and moderate sensitivity in the evaluation of serous effusions. A tiered classification scheme can improve the consistency of terminology for reporting SEC results, thus improving communication between the pathologists and clinical team, and quality of patient care.

Needle Biopsy Adequacy in the Era of Precision Medicine and Value-Based Health Care

CONTEXT.—

Needle biopsy of diseased tissue is an essential diagnostic tool that is becoming even more important as precision medicine develops. However, the capability of this modality to efficiently provide samples adequate for diagnostic and prognostic analysis remains quite limited relative to current diagnostic needs. For physicians and patients, inadequate biopsy frequently leads to diagnostic delay, procedure duplication, or insufficient information about tumor biology leading to delay in treatment; for health systems, this results in substantial incremental costs and inefficient use of scarce specialized diagnostic resources.

OBJECTIVE.—

To review current needle biopsy technology, devices, and practice with a perspective to identify current limitations and opportunities for improvement in the context of advancing precision medicine.

DATA SOURCES.—

PubMed searches of fine-needle aspiration and core needle biopsy devices and similar technologies were made generally, by tissue site, and by adequacy as well as by health economics of these technologies.

CONCLUSIONS.—

Needle biopsy adequacy can be improved by recognizing the importance of this diagnostic tool by promoting common criteria for needle biopsy adequacy; by optimizing needle biopsy procedural technique, technologies, clinical practice, professional education, and quality assurance; and by bundling biopsy procedure costs with downstream diagnostic modalities to provide better accountability and incentives to improve the diagnostic process.

Role of Ancillary Techniques in Fluid Cytology

The cytologic evaluation of serous effusions may be challenging for a number of reasons. Distinction of benign, reactive conditions from malignancy represents the main focus when examining these specimens. The morphologic diagnosis of malignancy may be difficult due to the relative paucity of abnormal cells. In other situations, cellularity is not an issue, but the ability to confidently identify a second, foreign (i.e., tumor) population within a background mesothelial cells on the basis of cytomorphologic features alone may pose problems. Cases with definitive morphologic evidence of malignancy may require additional studies in order to determine the tumor subtype and, in the case of carcinoma, the primary site of origin. Cases in which a definitive and precise diagnosis of malignancy is made may be optimal candidates for further molecular testing in order to gain prognostic information and guide personal therapeutic decisions. Finally, while an inflammatory or infectious condition can be suggested on the basis of cellular components and associated background elements, the identification of causative agent(s) may be difficult without additional studies. In all of these situations, the use of ancillary studies and techniques is critical; their utility and appropriate application are the subject of this review.