EX-VIVO FINE-NEEDLE ASPIRATION CYTOLOGY AND FLOW CYTOMETRIC PHENOTYPING IN THE DIAGNOSIS OF LYMPHOPROLIFERATIVE DISORDERS - A PROPOSED ALGORITHM FOR MAXIMUM RESOURCE UTILIZATION

Surface marker characterization of lymphoproliferative disorders is an essential component in the diagnostic work-up of these lesions. Immun ohistochemical surface marker analysis (SMA) is somewhat costly, fixat ion-dependant, and difficult to objectively quantitate. Two-color flow cytometric (TCFCM) SMA allows for more quantitative dual marker analy sis of a wide range of surface antigens, and is less expensive. Ex viv o fine-needle aspiration (xvFNA) has been reliably used for FCM DNA an alysis. The procedure has also been used to harvest tumor cells for xe notransplantation. In this study, we attempted to test the reliability of material obtained by xvFNA for SMA. We also designed an algorithm initiated by cytological assessment of the xvFNA smears in order to ta ilor the panel of antibodies required for TCFCM SMA of the aspirates. We performed 20 xvFNAs on freshly resected specimens from 19 patients with suspected lymphoproliferative disorders. The specimens included 1 2 lymph nod biopsies, seven splenectomies, and on breast biopsy. There were 10 male and nine female patients with a median age of 58 yr. The aspirate cell suspensions were examined by FCM within 24 hr of harves ting. The number of markers used ranged from four to 14 with an averag e of eight. The diagnoses included non-Hodgkin's lymphoma (n=5), lymph ocytic leukemia (n=5), reactive lymphoid hyperplasia (n=8), and Hodgki n's disease (n=1). Combining cytological assessment of the xvFNA smear s and TCFCM SMA, the diagnosis was reached prior to histopathologic ex amination in 17 cases (90%). The two remaining cases showed a reactive pattern on cytology and a polyclonal FCM SMA profile, and the diagnos is of sarcoidosis and toxoplasmosis was made on histological examinati on. Our study suggests that xvFNA provides adequate material for TCFCM SMA. An algorithm combining xvFNA cytology, FCM SMA, and histological examination is appropriate for the diagnosis of lymphoproliferative d isorders in most instances with maximal resource utilization and minim al expense. (C) 1997 Wiley-Liss, Inc.