Fine-needle aspiration (FNA) biopsy has proven to be a rapid, cost-effective, and accurate means for evaluating a wide variety of conditions in almost any organ system. In some situations, conditions resulting in reactive lymphadenopathies can be discerned on clinical grounds, and many require no specific therapy. However, cases in which an atypical presentation or a prolonged clinical course occurs warrant further investigation of the enlarged lymph nodes, often with the aim of ruling out a malignancy. In such cases, FNA biopsy can provide a rapid and accurate means of ruling out lymphoma and metastatic disease. With the aid of flow cytometry, reactive lymphoid hyperplasia can be readily assessed. Discerning the exact cause of a reactive lymphadenopathy by FNA biopsy can be problematic but can be aided with an appropriate serologic workup (ie, toxoplasma titers, Epstein-Barr virus titers). Granulomatous lymphadenitis may be caused by mycobacterial or fungal organisms, which can be grown in culture or detected by modern molecular studies performed on the aspirated material (ie, PCR). Rapid and accurate assessment of metastatic disease, particularly carcinomas and melanomas, is readily accomplished by FNA biopsy, with an overall sensitivity, specificity, and accuracy of over 90%. In these cases, cell block material can be obtained for additional useful prognostic information.
CASE REPORTT he patient was a 65-year-old man with a month-long history of enlarged lymph nodes in the left anterior cervical region. He had no prior malignancy and had had no recent dental work. Palpable lymph nodes were noted in the left anterior cervical chain. The lymph nodes were from 0.3 to 0.5 cm in diameter, firm, mobile, and slightly tender. The overlying skin appeared normal. Oral examination revealed no lesions. A fine-needle aspiration (FNA) biopsy was performed. Immediate evaluation revealed a mixed population of small and large lymphocytes and tingible body macrophages, suggesting a reactive process (Fig. 1A-D). Given the patient's age, additional passes were obtained for flow cytometry studies. Flow cytometry revealed CD19-positive B-cells that were polyclonal by and light chain expression (Fig. 1E, F). The findings were consistent with a reactive process. The patient was observed, and the lymphadenopathy resolved over the next several weeks.
DISCUSSIONFNA biopsy is a rapid, cost-effective, and accurate means for the workup of lymphadenopathy. Often, an aspirated specimen provides sufficient information for appropriate patient triage, ie, to decide if a patient requires simple observation, antimicrobial therapy for an infection, or additional tissue for workup in the form of a core or excisional lymph node biopsy. FNA biopsy evaluation of lymphadenopathies requires strict adherence to the cytopathologic principal of the "triple test," ie, correlation of the cytologic findings with the clinical and radiographic findings. The etiology of lymphadenopathy is extensive and runs the gamut from innocuous/self-limited processes, to in...