FINE-NEEDLE ASPIRATION CYTOLOGY OF SARCOMA - RETROSPECTIVE REVIEW OF DIAGNOSTIC UTILITY AND SPECIFICITY

Fine-needle aspiration cytology (FNA) is useful because of its low cos t, quick turn around time, and low incidence of complications. This st udy investigates the role FNA plays in the evaluation of sarcoma. We r eviewed all the pathologic material from patients with sarcoma or a FN A diagnosis suggestive of sarcoma at the University of California-Davi s Medical Center (1985-1994). Fifty-two of 196 patients identified (26 .5%) were evaluated with FNA exhibiting 46 soft tissue and 6 bone lesi ons located in the extremities (19), trunk (19), head and neck (8), re troperitoneum (3), and abdominal cavity (3). Among 196 patients identi fied, those evaluated by FNA had soft tissue rather than bone lesions (P < .001) and primary sites other than in the extremities (P < .001). The primary neoplasms for the 52 FNA patients included 47 sarcomas (1 0 malignant fibrous histiocytomas and 16 other types), I intramuscular myxoma, 2 lymphomas, and 2 spindle cell (sarcomatoid) carcinomas. In 43 patients (22% of total), FNA was used first, before a primary diagn osis. The FNA report showed the correct specific neoplasm in only 20.9 %. However, the FNA reports reflected an effective positive diagnosis leading to appropriate diagnostic biopsy in 88.4%, while only 7.0% wer e misleading (benign or inflammatory) and 4.6% inadequate. Review of F NA slides for 32 of 43 patients in which FNA was used first, in a blin ded fashion, exhibited 21.9% specificity for the specific neoplasm, an d 88.4% effective positive diagnoses. In 9 patients, FNA was utilized to investigate recurrence. Five out of 5 instances of recurrent sarcom a we,re identified by FNA. However, FNA misidentified recurrence in 3/ 4 instances, exhibiting suspicious cells from regenerating skeletal mu scle (2) and a traumatic neuroma (I). The specific diagnosis for sarco mas is challenging even with surgical material. FNA usually does not p rovide a specific diagnosis (only in 20.9% of cases) and review of rou tinely prepared slides showed the same specificity as reflected by the original FNA report, at times formulated with the benefit of immunohi stochemistry or electron microscopy. FNA effectively evaluated lesions in 45 of 52 patients (86.5%), confirming the useful screening role fo r this technique in sarcomas. (C) 1996 Wiley-Liss, Inc.