A Basic Approach to Lymph Node and Flow Cytometry Fine-Needle Cytology

Abstract

According to the World Health Organization (WHO), the new classification of lymphomas is mainly based on morphological, immunophenotypical, and molecular criteria. Consequently, this new approach has led from the substantial role that architecture played in the past to a secondary panel highlighting the role of fine-needle biopsy (FNB). Applied together with other ancillary techniques, such as flow cytometry (FC), FNB is a potential tool for the diagnosis of lymphomas, and enlarged lymph nodes represent an excellent target for the implementation of this technique. Despite the difficulties inherent in this technology, which might pose problems in differential diagnosis, in the majority of cases this joint work allows an accurate diagnosis of malignancy and even correct subcharacterization in routine lymphomas. Additionally, in selected cases, other molecular techniques like FISH and PCR can also be performed on FNB specimens, helping in the characterization and diagnosis of lymphomas. In this review, we discuss the basic aspects of the combination of FNB cytology and FC in the diagnosis and subclassification of lymphomas. The preanalytical phase is extensively discussed. The advantages, disadvantages, and technical limitations of this joint work are addressed in general and in terms of the accurate subclassification of lymphomas.

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

“…The main advantages shared by cytospins and LBC are the capacity of concentrating cells from low‐cellularity samples and the possibility of multiple slides with a clean background that facilitates ICC and its interpretation. Good ICC results can be obtained for different antibodies, including κ and λ chainS, which are mandatory in lymphoma and whose interpretation may be difficult in CB and smears due to the excessive background signal . Conversely, disadvantages of ICC on cytospins and LBC are the lack of appropriate and validated cytologic controls and the limited number of slides obtained, which may not be sufficient for a final diagnosis.…”

“…Being aware of these limitations is important when dealing with LN‐FNC, so that additional passes can be performed to enrich cell suspensions. Even when FC is available, cytospins should be prepared for those antibodies that are not routinely used in FC but may be useful in the differential diagnosis of lymphoma, such as cyclin D1, CD30, CD15, PAX5, Ki67 and MUM1, or for the characterisation of metastases. Another advantage of cytospin and LBC when compared to FC is the possibility to detect and immunostain large cells (large‐cell NHL, Reed‐Sternberg or Hodgkin cells) that are not detected by FC or rare neoplastic cells with severe necrosis, such as Reed‐Sternberg cells in HL and malignant B cells in T‐cell‐rich large B‐cell lymphoma.…”

‘Six Memos' for Lymph Node Fine-Needle Cytology and Flow Cytometry

“…Perfect technical procedures and preanalytical interpretation of the smear are essential conditions for a successful analysis. The article by Barroca and Marques [7] describes the technical basis and preanalytical evaluations of FC, as well as the basis for a correct application. FNC diagnosis and classification of non-Hodgkin lymphoma (NHL), which was once considered impossible, is now an acknowledged diagnostic possibility, despite its limitations.…”

Microfluidic chip technology applied to fine‐needle aspiration cytology samples for IGH clonality assessment

“…[1][2][3] However, even when FNC is combined with FC, a definitive FNC/FC diagnosis of B NHL is not obtained in 5%-15% of cases. In fact, the combination of FNC with flow cytometry (FC) immunophenotyping improves the diagnosis of B-cell non-Hodgkin lymphoma (NHL).…”

“…In fact, the combination of FNC with flow cytometry (FC) immunophenotyping improves the diagnosis of B-cell non-Hodgkin lymphoma (NHL). [1][2][3] However, even when FNC is combined with FC, a definitive FNC/FC diagnosis of B NHL is not obtained in 5%-15% of cases. 4,5 In such cases, immunoglobulin heavy chain (IGH) molecular clonality testing is required.…”