The role of fine-needle aspiration biopsy and flow cytometry in the evaluation of persistent neck adenopathy

BACKGROUND: The role of fine-needle aspiration biopsy (FNAB) and flow cytometry (FCM) in the evaluation of persistent neck adenopathy has not been completely defined. METHODS: All patients who underwent FNAB of an abnormal lymph node from 1990 to 1997 were identified, and the results of FNAB and FCM were correlated with histology or clinical follow-up. RESULTS: FNAB was performed on 133 patients with an abnormal lymph node in the neck. FNAB was malignant in 82 (62%), atypical in 13 (10%), benign in 27 (20%), and nondiagnostic in 11 (8%) patients. FNAB was compared with histologic results in 114 (86%) or with the results of clinical follow-up (average 17 months) in 12 patients (9%). Seven patients (5%) were lost to follow-up. Lymphoma and metastatic carcinoma were diagnosed in 25 (19%) and 76 (57%) patients, respectively. Sensitivity of FNAB and FCM was 96% and 100%, respectively, and specificity was 58% and 100%, respectively. Patients with Hodgkin’s lymphoma accounted for 80% of false negative FCM results. FCM was nondiagnostic in 3 of 34 patients (9%). Definitive subclassification of lymphoma was accomplished in only 3 of 17 (18%) patients in whom FCM was performed. CONCLUSIONS: FNAB is reliable in identifying metastatic disease, non-Hodgkin’s lymphoma, and reactive lymphadenopathy in the neck. FNAB and FCM still have a limited role in definitive diagnosis of Hodgkin’s lymphoma and classification of non-Hodgkin’s lymphoma, underscoring the importance of excisional biopsy.