Diagnostic pitfalls in fine needle aspiration biopsy of the spleen.

Fine needle aspiration (FNA) of the spleen is rarely performed, due to fear of procedure complications. The objective of this study is to review the cytologic diagnoses of aspiration biopsy of the spleen performed in a cancer center. Archival material (9-year period) was reviewed and correlated with histologic and ancillary test results, when available.Forty-one splenic FNA specimens were identified. There were no reported procedure complications. Nineteen cases were diagnosed as malignant. Of these, 11 were lymphomas. Nineteen cases were diagnosed as benign. There was one false-negative case and four false-positive cases. Primary splenic neoplasms were rare and misinterpreted as malignant. It is important to be familiar with the normal cytology of this uncommonly aspirated organ in order to successfully identify neoplastic and malignant processes. The use of ancillary studies is important in the definitive classification of benign and malignant splenic lesions.