Fine-needle aspiration cytology of hematopoietic lesions from multiple sites

We reviewed 130 fine-needle aspiration (FNA) biopsies from 118 patients with a variety of benign and malignant hematopoietic lesions. There were 74 (57%) malignant, 45 (35%) benign, and 11 (8%) atypical diagnoses. Immunocytochemistry of the aspirated material was performed in 47 (36%) and electron microscopy in 4 (3%) of the cases. FNA cytology was utilized to make a primary hematopoietic malignant diagnosis in approximately half of the cases and to confirm recurrence in the remainder. The malignant cases included non-Hodgkin's lymphoma. Hodgkin's disease, medullary and extramedullary plasmacytoma, and granulocytic sarcoma. Forty-two malignant cases had either previous or follow-up surgical biopsy with no false-positive diagnoses. Of the 11 atypical cases, seven had surgical confirmation with five malignant and two benign diagnoses. The benign hematopoietic lesions correctly identified included acute and chronic lymphadenitis, granulomatous processes, and eosinophilic granuloma. Only 5 of the 45 benign FNA biopsies had surgical pathology follow-up, with no false-negative diagnoses. The most commonly aspirated sites were lymph nodes (71%), although hematopoietic lesions were correctly identified in a number of extranodal locations, including soft tissue (8%), abdominal viscera (6%), lungs (5%), mediastinum (2.5%), bone (3%), and thyroid, salivary gland, and breast (1.5% each). This study demonstrates the clinical utility and diagnostic accuracy of FNA cytology in the evaluation of benign and malignant hematopoietic disorders from multiple sites. Ancillary studies performed on the aspirated material aided in making a specific and accurate diagnosis.