Fine needle aspiration evaluation of pancreatic lymphoma: A retrospective study of 25 cases in a single institution.

BACKGROUND: Accurate diagnosis of pancreatic lymphoma is crucial for clinical management. We evaluate the role of fine-needle aspiration (FNA) in the diagnosis of pancreatic lymphoma with the aid of flow cytometry and/or immunohistochemistry on the cell block.

METHODS: Cases of pancreatic lymphoma were collected by searching our pathology laboratory information system over a period of 16 years. The clinical findings, cytologic features, and immunophenotypic results were reviewed. The diagnoses of FNA were correlated with surgical specimens in a subset of FNA cases.

RESULTS: A total of 25 FNA cases of pancreatic lymphoma were included. The most common type of pancreatic lymphoma was large B cell lymphoma followed by follicular lymphoma. With the aid of flow cytometry and immunohistochemical work-up on cell block, 72% (18/25) of the cases were diagnosed as lymphoma and 16% of the cases (4/25) were diagnosed as suspicious for lymphoma by FNA. Only two cases (8%) including one false negative and one nondiagnostic aspirate missed the lymphoma diagnosis and 1 case (4%) was indeterminate by FNA evaluation.

CONCLUSION: FNA demonstrated high accuracy in rendering diagnosis of pancreatic lymphoma. The overall sensitivity is 88% and the false negative and nondiagnostic rates are 4%, respectively. Further subtyping of certain lymphomas can be difficult due to the lack of architectural features of FNA specimens.