Spectrum of cytomorphological features of extranodal NK/T‐cell lymphoma, nasal type

Abstract

Objective: Extranodal natural killer/T-cell lymphoma, nasal type (ENKTL) is an aggressive extranodal lymphoma of NK-cell or T-cell lineage. Its clinical features overlap with those of several sinonasal mass lesions. While the histopathological features are well described, diagnosis is often difficult, owing to presence of extensive coagulative necrosis, so that repeated biopsies may sometimes be necessary for correct diagnosis. Literature on cytological findings of ENKTL is limited. Methods: Cytomorphological features of cases of histologically confirmed ENKTLhaving corresponding cytology samples were reviewed retrospectively, to identify distinctive features that could possibly suggest this entity. Results:Aspirates from five patients were studied: four from cervical nodes, one from cheek swelling and one from pleural fluid. Two aspirates were reported as positive for malignancy, two as atypical lymphoid proliferation and one was non-diagnostic. Pleural fluid was reported as malignant, favouring a diagnosis of carcinoma. On cytology, aspirates showed medium to large cells with folded, indented nuclei and abundant pale cytoplasm, some with tongue-like cytoplasmic protrusions. A distinctive feature was presence of large loose clusters of tumour cells with arborising capillaries running through them. Interestingly, necrosis was consistently absent.Subsequent biopsies from palate (three cases) and nasal masses (two cases) confirmed the diagnosis of ENKTL.Conclusions: Suspicion of ENKTL on cytology is crucial for timely diagnosis to avoid diagnostic delay, especially when only highly necrotic biopsy samples are available.Awareness of distinctive cytomorphological features is required to make fine needle aspiration an effective diagnostic tool for initial diagnosis and for evaluation of possible recurrences. K E Y W O R D Saspiration cytology, fluid cytology, haematolymphoid, NK/T-cell lymphoma, sinonasal

Malignant effusions from extranodal NK/T‐cell lymphomas are frequently of anaplastic morphology with azurophilic granules and of T‐cell lineage

“…To date, there are only a handful of reported cases with very limited data on the cytological features. [8][9][10][11][12][13][14][15][16][17] In this study of four new cases of effusion ENKTL, we found that the neoplastic cells were frequently of large to anaplastic morphology with azurophilic granules.…”

“…ENKTL rarely involves pleural effusion or ascites, which may occur at disease progression. In the literature, there are only a few cases of ENKTL with lymphomatous effusions . Herein we report four new cases of effusion ENKTL and the results of literature review, focusing on the cytopathological features, immunophenotype, and cellular lineage in terms of T‐vs NK‐cell origin.…”

“…We searched PubMed for cases of ENKTL-related malignant effusion as of July 2019 and selected only cases with relatively complete clinicopathological findings. [8][9][10][11][12][13][14][15][16][17]19,20 Four literature cases without confirmed EBV association were excluded. 8,11,17,19 We identified a total of 12 cases in the literatures.…”

“…In the literature, there are only a few cases of ENKTL with lymphomatous effusions. [8][9][10][11][12][13][14][15][16][17] Herein we report four new cases of effusion ENKTL and the results of literature review, focusing on the cytopathological features, immunophenotype, and cellular lineage in terms of T-vs NK-cell origin. Interestingly, we found that effusion ENKTL was characterized by anaplastic large cell morphology, presence of cytoplasmic azurophilic granules, and a higher proportion of T-cell lineage as compared to de novo tumors arising from the prototypic sites.…”

The role of cytology in the diagnosis of haematological malignancies

“…The cytological diagnosis of two different types of T cell malignancies is discussed in the two papers by Kanwalpreet et al and Kobata et al . The former is a retrospective analysis of histologically confirmed cases of extranodal nasal type NK/T cell lymphomas.…”