Lymphoreticular malignancies in serous effusions: Cytomorphologic, flow cytometric and immunocytochemical analysis

The urgency of Burkitt lymphoma diagnosis in fluid cytology-A tertiary care experience

BACKGROUND

Burkitt lymphoma (BL) is an aggressive high-grade B-cell non-Hodgkin lymphoma commonly diagnosed in young age and is known to involve extra nodal sites. But the involvement of body fluids by BL is an uncommon presentation. Rapid diagnosis of BL is vital to prevent complications like tumour lysis syndrome. Cytological examination of body fluids continues to be an indispensable tool for rapid diagnosis of BL.

OBJECTIVES

In this study, we aim to study the clinical, cytomorphological and immunophenotypic characteristics of BL involving serous effusions and other fluids.

MATERIALS AND METHODS

In this retrospective study, 17 cases reported as BL in fluid cytology from 2016 to 2022 were collected and reviewed. We performed a comprehensive analysis of the clinical data, cytomorphological features, immunophenotyping data along with the haematological workup of these cases. We have also compared with the histopathological diagnosis for those cases where biopsy was available.

RESULTS

BL more commonly involved ascitic fluid (52%), followed by pleural fluid (4 cases) and cerebrospinal fluid (CSF; 4 cases). Primary diagnosis of BL in fluid was done in 88% of the cases. Bone marrow involvement was noted in two cases. Cytological smears showed discrete monomorphous population of medium-sized atypical lymphoid cells with frequent apoptotic bodies. Classic cytoplasmic punched out vacuoles were observed in 88% of the cases. Immunophenotyping data was available for 12 cases in which tumour cells showed positivity for CD20 (100%), CD10 (4 of 7 cases), BCL6 (3 of 5 cases) and cMYC (7 of 7 cases-100%) and were negative for Terminal deoxynucleotidyl transferase (TdT) (11 of 11 cases). Mean Ki67 labelling index was 95%. Histopathological diagnosis was available for 9 cases, and there was 100% agreement between cytological and histopathological diagnosis in 7 cases.

CONCLUSION

Precise diagnosis of BL can be rendered in body fluids by identification of classic cytomorphological features and by performing supportive ancillary tests in fluids for immunophenotyping.

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.

[Cytology of body cavity fluids - established methods and new developments]

BACKGROUND

Body cavity fluids are among the most frequently examined samples in cytology. Cytomorphology is supplemented by additive testing. An international system of terminology and classification has been recently presented.

OBJECTIVES

Cytopreparation and staining techniques as well as some exemplary morphological patterns are presented. "The International System for Serous Fluid Cytopathology" (TIS) is briefly presented.

MATERIALS AND METHODS

Pleural effusion, pericardial effusion, and ascites: special technical issues, immunocytochemistry, molecular diagnostics, and reporting system issues are discussed.

RESULTS

Body cavity fluids are important samples that provide significant information. Additive testing is established for routine use. The form and structure of reports is widely divergent in practical use.

DISCUSSION

A reporting system for serous fluid cytopathology that is easily applied and recognized internationally is highly desirable. TIS is a valuable approach to this goal.

Flow cytometric immunophenotyping in a liquid-based cytology sample of pleural fluid: Connecting the dots

Primary mediastinal large B-cell lymphoma (PMBCL) is an uncommon non-Hodgkin lymphoma that is rarely described in cytology samples. The present study highlights the importance of flowcytometric immunophenotyping and immunocytochemistry in an effusion sample of an uncommon case of PMBCL.