Value of fine needle aspiration cell blocks in the diagnosis and classification of lymphoma.

Fine needle aspiration biopsy (FNAB) is a simple yet accurate diagnostic procedure. However, the role of FNAB in lymphoma diagnosis and classification remains controversial. This study aimed to evaluate the value of FNAB cell blocks in the diagnosis and classification of lymphoma using our patented aspirator in a pencil-grip operation manner and a simplified cell block preparation method. We retrospectively reviewed 177 cases of lymph node and extranodal lymphoproliferative disorders that were diagnosed with cytomorphology, morphology, and immunohistochemistry of cell blocks. Of these, 83 were primary lymphoma; 14 were recurrent lymphoma; 8 were suspected as lymphoma, and 72 were benign reactive hyperplasia (BRH). Our analysis indicated 99.0% sensitivity, 95.9% specificity, 97.1% positive predictive value, and 98.6% negative predictive value in discriminating among primary/recurrent lymphoma and BRH. The diagnostic accuracy for sub-classification of lymphoma was 86.6% (84/97), with 77.8% (7/9) for classical Hodgkin's lymphoma and 87.5% (77/88) for non-Hodgkin's lymphoma. Our results implicated cell blocks as a reliable and useful adjunct to FNAB for the diagnosis and classification of lymphoma. Cytomorphology, morphology, and immunohistochemical studies of cell blocks offered very high accuracy in the diagnosis of lymphoma and allowed further sub-classification in many cases. Thus, patients with a definitive diagnosis and classification might avoid invasive and expensive surgical biopsy procedures.