Management of cytologic material, preanalytic procedures and biobanking in lymph node cytopathology

The Current and Future Impact of Lymph Node Fine-Needle Aspiration Cytology on Patient Care

Lymph node (LN) fine-needle aspiration cytology (FNAC) is a common diagnostic procedure for lymphadenopathies. Despite the qualities and potentialities of LN-FNAC, the number of possible pathologies and the variety of clinical contexts represent a challenge and require a continuous upgrading of the procedure according to the emerging clinical requests and new technologies. This study presents an overview of the current and future impact of LN-FNAC on the care of patients with lymphadenopathy.

Cytological Diagnosis of Aggressive Small-Cell Lymphomas

BACKGROUND

Despite their sometimes deceivingly bland appearance, some small-cell lymphomas are very aggressive and the prognosis of patients depends on a prompt diagnosis that allows the initiation of appropriate therapy.

SUMMARY

The present review discusses the salient cytological features of the most common aggressive small-cell lymphomas and then proceeds to analyze their main diagnostic criteria, including the usage of ancillary techniques.

KEY MESSAGES

Lymph node fine-needle aspiration cytology is a fast, safe, cheap, minimally invasive, and accurate procedure that can be used for a prompt and accurate diagnosis of lymphomas.

[New aspects in fine needle biopsies of the lymph nodes]

BACKGROUND

The cytology of lymph nodes is a cost-effective method with a short turnaround time and low risk to patients that delivers valuable information on the cause of the lymphadenopathies.

OBJECTIVES

To discuss the value of lymph node cytology in the diagnosis of lymph node swellings.

METHODS

Analysis of the causes of the controversially discussed aspects of lymph node cytology. Presentation of the diagnostic groups of lymph node cytology according to the Sydney system.

RESULTS

The technical aspects of lymph node sampling during fine needle biopsy, as well as the subsequent preparation of the correctly fixed direct smears and the triage of the sample for the auxiliary studies, may pose a significant challenge for some puncturers. The whole spectrum of modern pathologic auxiliary studies can be applied to correctly triaged cytologic samples. The diagnoses of fine needle biopsies of the lymph nodes can be divided into five groups according to the recently proposed Sydney reporting system: insufficient/non-diagnostic, benign, atypical, suspicious, and malignant. Further details concerning the diagnosis as well as recommendations on how to proceed are additionally included in cytologic reports.

CONCLUSIONS

The improvement of lymph node sampling as well as the technical aspects of the sample handling, including the application of auxiliary studies, considerably increase the diagnostic value of fine needle biopsy of the lymph nodes. Wide implementation of the usage of the diagnostic groups for reporting fine needle biopsies of the lymph nodes can standardize reporting and improve communication with other clinical specialists.

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 performance of melanocytic markers for immunocytochemical evaluation of lymph-node melanoma metastases on cytological samples

AIMS

The diagnosis of metastatic cutaneous melanoma (CM) on lymph node fine needle aspiration samples may be challenging and usually requires confirmation by immunocytochemistry. However, the cytological material could be too scant to order a broad panel of markers. In this case, the pathologist is forced to choose the most advantageous antibodies. The most commonly used melanocytic markers include S100, Melan-A, HMB45 and SOX10 but their diagnostic yield on cytological samples has been poorly studied. The current work aimed to evaluate the diagnostic performance of melanocytic markers when applied to cell blocks obtained from fine needle aspiration cytology (FNAC) of lymph node metastases from CM.

METHODS

S100, Melan-A, HMB45 and SOX10 were tested on cell block sections of 38 lymphnode metastases from CM diagnosed by cytology. A combined score was built to evaluate each immunostaining, considering the intensity of the staining and the percentage of stained neoplastic cells.

RESULTS

S100 and SOX10 revealed a higher sensitivity (100%) than Melan-A and HMB45 for the diagnosis of metastatic CM. Furthermore, SOX10 emerged as the melanocytic marker with the best staining performance.

CONCLUSION

SOX10 has a 100% detection rate and the most easily interpretable staining pattern compared with other melanocytic markers. Therefore, it is strongly recommended that SOX10 is included in the minimal immunocytochemical panel for the diagnostic evaluation of lymph node FNAC in patients with suspected CM metastasis.

Real-world experience with the Sydney System on 1458 cases of lymph node fine needle aspiration cytology

INTRODUCTION

Lymph node (LN) fine needle aspiration cytology (FNAC) is a safe, quick, inexpensive, reliable, and minimally invasive technique for the diagnosis of lymphadenopathies. Recently, an international committee of experts proposed guidelines for the performance, classification, and reporting of LN-FNAC: the Sydney System. We set out to analyse the diagnostic performance of the Sydney System in a retrospective study.

METHODS

We retrieved 1458 LN-FNACs, reformulated the diagnoses according to the Sydney System, and compared them to the histological control where available (n = 551, 37.8%).

RESULTS

The risk of malignancy for each of the five categories was 66.7% for inadequate/insufficient, 9.38% for benign (overall: 0.84%), 28.6% for atypical, 100% for suspicious and 99.8% for malignant. LN-FNAC showed a sensitivity of 97.94%, a specificity of 96.92%, a positive predictive value of 99.58%, and a negative predictive value of 86.30%.

CONCLUSIONS

These data support the usage of LN-FNAC as an agile first-level technique in the diagnosis of lymphadenopathies. The Sydney System supports and enhances this role of LN-FNAC, and its adoption is encouraged. In negative cases, coupled with ancillary techniques, LN-FNAC can reassure the clinician regarding the benignity of a lymphadenopathy and indicate the need for clinical follow-up, which will catch possible false negatives. In positive cases, LN-FNAC can provide sufficient information, including predictive biomarkers, to initiate management and obviate the need for subsequent, more invasive procedures. Given its speed, minimal invasiveness, and low cost, LN-FNAC can be performed in most cases, even when more invasive techniques are not feasible.

Image-guided lymph node fine-needle aspiration: the Johns Hopkins Hospital experience

INTRODUCTION

Although the diagnostic utility of lymph node fine-needle aspiration (FNA) is well established in the evaluation of metastatic malignancy, its value in the diagnosis of lymphoma is more controversial; yet, there is a growing trend among practitioners towards less-invasive procedures such as FNA and core needle biopsy (CNB). The guidelines recently published by the American Society for Clinical Pathology/College of American Pathology (CAP) regarding the workup of lymphoma include recommendations on the value and limitations of FNA.

MATERIALS AND METHODS

We reviewed 1237 image-guided lymph node aspirates from 695 procedures (410 nodes from 360 ultrasound [US]-guided cases, 799 from 309 endobronchial ultrasound [EBUS], 25 from 23 endoscopic ultrasound [EUS], and 3 from 3 computed tomography [CT]).

RESULTS

The majority (40 of 46, 87%) of lymph nodes suspected of lymphomatous involvement were aspirated under ultrasound. Core needle biopsy [CNB] was obtained for 41 (89%) lymph nodes, including all 40 US specimens. Flow cytometry (FC) was performed on 37 (80%) aspirates; aspirates without FC were from patients who had a history of Hodgkin lymphoma, or showed granulomata or non-hematologic malignancy onsite. Thirty-one (67%) lymph nodes were sent for review by hematopathology. Forty-two (91%) lymph node FNA/CNB yielded actionable diagnoses. Seventeen of 241(7%) cases aspirated for other indications (14 US, 3 EBUS) were involved by a lymphoproliferative process. All were reviewed by hematopathology. All 14 US cases had FC and CNB.

CONCLUSION

Our institutional approach towards lymph node cytopathology for lymphoma workup appears to be in accordance with the new CAP guidelines, and demonstrates a potential triage and workflow model for lymph node FNA specimens that allows for accurate diagnosis in cases where lymphoma is a consideration.

Time-related changes in cell morphology and biomarker immunoreactivity for cells stored in a buffer-based cell medium

OBJECTIVE

Buffer-based cell media (BBCM) are a valuable tool in the post-collection processing of cytology samples, though with poorly defined effects on cell properties. In this study, time-related changes in cell morphology and biomarker immunoreactivity were evaluated for cells stored at room temperature in a BBCM prepared with bovine serum albumin (BSA) and ethylene diamine tetraacetic acid (EDTA).

METHODS

Cytospins were prepared at five consecutive 24-hour intervals (0, 24, 48, 72, 96) from three human cell lines (MCF7, SK-MEL-28, FaDu) suspended and stored in BBCM. Preservation of cell morphology was evaluated on Papanicolaou-stained cytospins from the percentages of apoptotic cells. Preservation of immunoreactivity was evaluated for cytokeratins, oestrogen receptors, Ki67, and melanoma markers from the percentages of cells positive for the corresponding immunocytochemical reactions.

RESULTS

Cell morphology was well preserved for the majority of cells of the three lines stored for 24 and 48 hours (93%, 97%, 98% and 62%, 81%, 88%, respectively), while the majority of cells were apoptotic after 72 and 96 hours (70%, 47%, 39% and 77%, 70%, 59%, respectively). The immunoreactivity of cytokeratins remained unchanged during the entire 96 hours, while that of melanoma markers (S100, HMB45, Melan-A) decreased by 27%, 2%, and 3%, respectively. The immunoreactivity of oestrogen receptors and Ki67 decreased by 29% and 17% after the first 24 hours, and was completely lost after 96 hours.

CONCLUSIONS

A BBCM with the addition of BSA and EDTA facilitates good preservation of cell morphology and immunoreactivity of biomarkers for up to 48 hours at room temperature.

Lymph node fine needle aspiration cytology (FNAC) in paediatric patients: Why not? Diagnostic accuracy of FNAC in a series of heterogeneous paediatric lymphadenopathies

Fine needle aspiration cytology (FNAC) can be a precious tool for the evaluation of lymphadenopathies in children and adolescents. The purpose of this study was to analyse the diagnostic accuracy of FNAC in a paediatric lymph node series. We report a series of 76 patients, aged up to 19 years, who underwent lymph node FNAC. In our series, 57 cases were diagnosed as non-neoplastic, including benign reactive hyperplasia and other inflammatory lesions, 18 cases were diagnosed as malignant and 1 case was diagnosed as suspicious for lymphoproliferative process, not otherwise specified. Sensitivity, specificity, positive predictive value and negative predictive value were 93 %, 100 %, 100 % and 98 %, respectively. Diagnostic accuracy resulted 98.6 %. FNAC is an accurate, minimally invasive method with minimal complications that allows evaluation of paediatric lymphadenopathies and a correct triage of reactive/inflammatory and neoplastic lymphadenopathies. The application of rapid on-site evaluation, the realization of a cell block and the application of ancillary diagnostic tests, including at least immunocytochemistry and flow cytometry, allows to achieve an excellent diagnostic performance.

A Proposal for the Performance, Classification, and Reporting of Lymph Node Fine-Needle Aspiration Cytopathology: The Sydney System

BACKGROUND

The evaluation of lymph nodes (LN) by fine-needle aspiration cytology (FNAC) is routinely used in many institutions but it is not uniformly accepted mainly because of the lack of guidelines and a cytopathological diagnostic classification. A committee of cytopathologists has developed a system of performance, classification, and reporting for LN-FNAC.

METHODS

The committee members prepared a document that has circulated among them five times; the final text has been approved by all the participants. It is based on a review of the international literature and on the expertise of the members. The system integrates clinical and imaging data with cytopathological features and ancillary techniques. The project has received the endorsement and patronage of the International Academy of Cytology and the European Federation of the Cytology Societies.

RESULTS

Clinical, imaging, and serological data of lymphadenopathies, indications for LN-FNAC, technical procedures, and ancillary techniques are evaluated with specific recommendations. The reporting system includes two diagnostic levels. The first should provide basic diagnostic information and includes five categories: inadequate/insufficient, benign, atypical lymphoid cells of undetermined/uncertain significance, suspicious, and malignant. For each category, specific recommendations are provided. The second diagnostic level, when achievable, should produce the identification of specific benign or malignant entities and additional information by utilizing ancillary testing.

CONCLUSION

The authors believe that the introduction of this system for performing and reporting LN-FNAC may improve the quality of the procedure, the report, and the communication between cytopathologists and the clinicians. This system may lead to a greater acceptance and utilization of LN-FNAC and to a better interdisciplinary understanding of the results of this procedure.

CD15, CD30, and PAX5 evaluation in Hodgkin's lymphoma on fine-needle aspiration cytology samples

BACKGROUND

The phenotypical identification of diagnostic cells is crucial for the diagnosis of Hodgkin's lymphoma (HL) on fine-needle aspiration cytology (FNAC). The aim of this study is to evaluate the immunocytochemical (ICC) expression of CD30, CD15, and PAX5 in Hodgkin's cells (HC) and Reed-Sternberg cells (RSC) on smears and cell-blocks (CB) of HL and to compare the performance of each antibody on smears and CB.

METHODS

In 21 FNAC cases of histologically confirmed classical HL, ICC identification of HC and RSC was performed using CD15, CD30, and PAX5 on smears and CB, respectively.

RESULTS

CD30 was positive in 19/21 cases (90.5%; 11/11 smears and 8/10 CB), CD15 was positive in 14/21 cases (66.7%; 5/11 smears and 9/10 CB), and PAX5 was positive in 13/21 cases (61.9%; 9/11 smears and 4/10CB).

CONCLUSIONS

CD15, CD30, and PAX5 are useful to the FNAC identification of HC and RSC. CD30 is the most sensitive, followed by CD15 and PAX5, which are more effective on CB and smears, respectively.

Lymph node fine-needle cytology in the era of personalised medicine. Is there a role?

The 2016 World Health Organisation revised classification of lymphoma has sub-classified well-defined entities and added a number of provisional entities on the basis of new knowledge on genetic, epigenetics and phenotypical data; prognostic and predictive features are also part of this classification. New knowledge on well-defined entities further enlightens the mechanisms of lymphomagenesis, which are more complex and multifactorial than once believed. Therapies are also more complex because traditional clinical trials have been integrated with new drugs and compounds with unique mechanisms of actions against distinct molecular targets. As lymphoma acquires additional genetic and phenotypic features over the time, pathological assessment is also necessary. Histological evaluation and tissue collection by surgical biopsies are necessary for phenotypical and molecular purposes; however, these are demanding procedures for both the patient and the health care system. At the same time, the choice of the best treatment for a specific entity, in different phases and different patients requires information that may not be available when the biopsy is performed. Fine needle aspiration cytology (FNAC) is successfully used in lymph nodes (LNs) in combination with different ancillary techniques and might be used to assess the phenotypic and genetic profile of specific targets and to get key information for therapy, in different phases and stages of the disease, with the option to re-check the same target over time, without surgical excision. This brief review describes LN-FNAC diagnostic criteria, current therapies for lymphomas and the potential role of LN-FNAC in selecting non-Hodgkin lymphomas patients for specific targeted treatments.