Introduction: Peripheral T-cell lymphoma (PTCL) accounts for 10-20% of all non-Hodgkin lymphomas in the United States. In this study, the authors reviewed the cytologic and immunophenotypic findings of 33 fine-needle aspirations (FNAs) of PTCL.
Methods: Thirty-three FNAs from 26 patients (12 females and 14 males) with PTCL were identified during 1991-1999. The patients' age ranged from 19 to 96 years. Immunophenotyping was performed in 24 cases by using either flow cytometry (FC; 21 cases) or immunocytochemistry (IC; 3 cases). Follow-up included review of prior or current histology and clinical records.
Results: Nine cases were associated with mycosis fungoides, three cases were classified as T-cell chronic lymphocytic leukemia, and two were angioimmunoblastic adenopathy (AILD)-like T-cell lymphoma. The remaining 19 were classified as PTCL, not otherwise specified. The latter consisted of eight mixed cell variant, eight large cell variant, and three anaplastic variant. One of the mixed cell variant and one of the large cell variants contained numerous epithelioid histiocytes (Lennert lymphoma). Thirty (91%) cases had a definitive diagnosis of malignant lymphoma. Twenty-two cases (2 IC and 20 FC) showed a predominant population of T lymphocytes without a monoclonal B-cell population. In addition, FC revealed an aberrant expression of T-cell markers in 13 cases. Two cases were interpreted as "atypical lymphoid population"; one case was an AILD-like T-cell lymphoma, and the other case was PTCL, large cell type. One case initially was interpreted as granulomatous lymphadenitis; subsequent biopsy revealed PTCL, Lennert type.
Conclusions: Peripheral T-cell lymphoma is a heterogeneous group of lesions with diverse cytomorphology. Cytologic analysis and immunophenotyping is an accurate method of diagnosing peripheral T-cell lymphoma.