Real-world experience with the Sydney System on 1458 cases of lymph node fine needle aspiration cytology.

These data support the usage of LN-FNAC as an agile first-level technique in the diagnosis of lymphadenopathies. The Sydney System supports and enhances this role of LN-FNAC, and its adoption is encouraged. In negative cases, coupled with ancillary techniques, LN-FNAC can reassure the clinician regarding the benignity of a lymphadenopathy and indicate the need for clinical follow-up, which will catch possible false negatives. In positive cases, LN-FNAC can provide sufficient information, including predictive biomarkers, to initiate management and obviate the need for subsequent, more invasive procedures. Given its speed, minimal invasiveness, and low cost, LN-FNAC can be performed in most cases, even when more invasive techniques are not feasible.