Utilization of fine-needle aspiration cytology and flow cytometry in the diagnosis and subclassification of primary and recurrent lymphoma

BACKGROUND. The primary diagnosis of non-Hodgkin's lymphoma/leukemia (NHL) by fine-needle aspiration (FNA) is controversial. The authors reviewed their experience with FNA and flow cytometry (FC) to determine the usefulness and limitations of these techniques in the diagnosis of NHL. METHODS. Slides and reports from all lymph node and extranodal FNAs performed during the period July 1993 to January 1997 with a diagnosis of lymphoma or benign lymphoid process were reviewed. Clinical and biopsy follow-up data were recorded. Results were tabulated and the usefulness of cytology was analyzed. RESULTS. There were 100 adequate aspirates from 87 patients. These included 72 cases of NHL, 58 (80%) of which were diagnosed by FNA and FC without the need for histologic sampling (69% of the primary lymphomas and 88% of the recurrent lymphomas). There were 22 aspirates suspicious for lymphoma, 12 equivocal results, and 7 benign diagnoses. Eighty-six percent of malignant FNAs (50 of 58) had flow cytometry (FC) as compared with only 15% (5 of 34) of the suspicious or equivocal FNAs. CONCLUSIONS. FNA is a valuable method for diagnosing and subclassifying NHL, although immunophenotyping by FC is often an essential ancillary rest. In our experience, correlating the FNA results with the FC results can eliminate the need for a more invasive surgical biopsy in many cases. Cancer (Cancer Cytopathol) 1998;84:252-61. (C) 1998 American Cancer Society.