Fine needle aspiration (FNA) cytology is a minimally invasive, rapid, and inexpensive technique. The accuracy of FNA in diagnosing benign and malignant lymph node diseases is over 90%; however, the sensitivity of this method varies greatly between benign and malignant, primary and secondary disease groups.

If exfoliative cytology is based on natural or artificially exfoliated cells to diagnose diseases, aspiration cytology is based on cells aspirated from tissues and organs with a small needle (with a diameter of ≤ 22G).