RESUMO
We reviewed the institutional experience with fine needle aspiration biopsy (FNAB) of peripheral lymph nodes in the Instituto Nacional de la Nutrición Salvador Zubiran from January 1988 to December 1992. A total of 298 FNAB had been performed in 288 patients. Aspirates with just blood, few stromal cells or with desiccation changes were excluded (63 cases), as well as those in whom it was not possible to establish a clinical or morphologic correlation (56 cases). In the 179 cases included, the FNAB diagnosis was histologically confirmed in 137 and in 42 cases the correlation was established by clinical follow-up and response to treatment. According to the diagnosis, aspirates were divided in benign and malignant in the analysis. We observed 70 aspirates (39%) with benign lesions and 109 (61%) with primary or metastatic neoplastic cells. The most frequent benign diagnosis was hyperplasia followed by epithelial metastatic neoplasms. In 25 aspirates there was a discrepant cyto-histologic diagnosis but only six were false negatives. No false positive or complications were identified. The FNAB in our cases showed: sensitivity 95%, specificity 100%, positive predictive value 100% and negative predictive value 91.4%. Our data support the value of FNAB as a reliable, safe, inexpensive and easy to perform method in the diagnosis of lymph node enlargements. Thus, we believe this method should be recommended as the initial approach in the study of lymphadenopathies.