Peripheral T-cell lymphoma not otherwise specified vs. Hodgkin's lymphoma on fine needle aspiration cytology

To study the morphologic features of peripheral T-cell lymphoma, not otherwise specified (PTCL, NOS) on fine needle aspiration cytology (FNAC) smears and to identify cytomorphologic features that would delineate them from features of cases of Hodgkin's lymphoma (HL).

Fourteen cases each of PTCL, NOS, and HL with adequate FNAC smears were retrieved. These cases were analyzed for 12 cytomorphologic features: presence of atypical lymphoid cells, percentage of large lymphoid cells, lymphoid cells with cleaved/indented nuclei, typical Reed-Sternberg (RS) cells, mononuclear cells with prominent eosinophilic macronucleoli, mononuclear cells with prominent nucleoli, histiocytes, eosinophils, plasma cells, polymorphonuclear leukocytes, vessels and perivascular clustering of atypical mononuclear/atypical lymphoid cells. Each of these features was evaluated for its presence or absence and was semiquantitated on a scale from 0 to +3.

The presence of atypical lymphoid cells with a spectrum ranging from small to intermediate and large was seen exclusively in cases of PTCL. Lymphoid cells with cleaved or indented nuclei, endothelium-lined vessels with perivascular clustering of tumor cells and absence of typical RS cells, and mononuclear cells with prominent eosinophilic macronucleoli emerged as the parameters significant in not only diagnosing cases of PTCL, NOS, but also in their delineation from cases of HL.

A careful analysis of cytomorphologic features can be useful in at least suggesting a diagnosis of PTCL and help to distinguish that diagnosis from HL, which the features may mimic. Immunophenotyping and molecular studies are important in arriving at a definitive diagnosis.