FNA cytodiagnosis of non-Hodgkin's lymphoma and its subtyping under working formulation of 175 cases.

One hundred thirty-two cases diagnosed as non-Hodgkin's lymphoma (NHL) by fine-needle aspiration cytology (FNAC) and histology, and 43 cases in which there were minor or major discrepancies between cytology and histology for diagnosis of NHL, were reviewed. The diagnostic accuracy of FNAC for NHL was 86.3% at the initial diagnosis. Following review, all the 132 cases initially diagnosed as NHL by cytology and histology remained so with minor changes in subtypes in a few cases. Of the 43 discrepant cases, 28 turned out to be NHL and 6 as Hodgkin's disease (HD); 3 were anaplastic carcinoma; and in 6 cases the discrepancy still persisted. Diagnostic accuracy of FNA for NHL improved to 98.0% following review. Categorization of histologically diagnosed NHL cases under working formulation showed that 10.4%, 21.5%, and 57.7%, respectively, were low, intermediate, and high-grade lymphomas. The corresponding figures were 16.6%, 18.4%, and 60.1%, respectively, in cytology. The diagnostic accuracy of cytology for subtyping was found to be 67.5%.