Negative pressure is not necessary for using fine-needle aspiration biopsy to diagnose suspected thyroid nodules: a prospective randomized study

Fine-needle aspiration biopsy (FNAB) can be used to diagnose thyroid cancer and other tumors. Although FNAB without negative pressure (FNAB？P) reduces the risk of blood contamination, FNAB with negative pressure (FNAB+P) increases the sensitivity of the biopsy results. Therefore, we performed a randomized study of FNAB with or without negative pressure to identify the better diagnostic method