title: Overcoming the limitations of fine needle aspiration biopsy: detection of lateral neck node metastasis in papillary thyroid carcinoma.
abstract: OBJECTIVE
  Ultrasound (US) and US-guided fine needle aspiration biopsies (FNAB) are considered the modalities of choice for assessing lymph nodes suspected of containing metastases, but the sensitivity of FNAB varies and is specific to the operator. We analyzed the risk of FNAB providing false negative results of lateral neck node metastasis, and evaluated diagnostic accuracy of FNAB, in patients with papillary thyroid cancer.
  
  
  METHODS
  FNAB was performed in 242 patients suspected of having lateral neck node metastasis on preoperative imaging. Thyroglobulin in the fine-needle aspirate washout (FNA wash-out Tg) and computed tomography enhancement (Hounsfield units) were measured. Patients with negative results on FNAB were examined by intraoperative frozen section. The false negative and true negative groups were compared.
  
  
  RESULTS
  Of the 242 patients, 130 were confirmed as having lateral neck node metastases. In 74 patients, the metastasis was identified by FNAB. False positive results were observed in 2 patients (0.8%) and false negatives in 58 (44.6%). Risk analysis showed that patient age <45 years (p=0.006), tumor size >1 cm (p=0.008) and elevated FNA wash-out Tg (p=0.004) were significantly associated with false negative results on FNAB. The accuracy of FNAB increased significantly when combined with FNA wash-out Tg (p=0.003).
  
  
  CONCLUSIONS
  To reduce the false negative rate of FNAB, patient age (<45 years), tumor size (>1 cm) and FNA wash-out Tg (>34.8 ng/mL) should be considered in preoperative planning. Accuracy may be improved by combining the results of FNAB and FNA wash-out Tg.
authors.affiliation: Department of Surgery, CHA Bundang Medical Center, CHA University, Seongnam, Korea.
authors.forename: Hak Hoon
authors.initials: HH
authors.lastname: Jun
authors.affiliation: Thyroid Cancer Center, Department of Surgery, Gangnam Severance Hospital, Yonsei University College of Medicine, Seoul, Korea.
authors.forename: Seok Mo
authors.initials: SM
authors.lastname: Kim
authors.affiliation: Thyroid Cancer Center, Department of Surgery, Gangnam Severance Hospital, Yonsei University College of Medicine, Seoul, Korea.
authors.forename: Bup Woo
authors.initials: BW
authors.lastname: Kim
authors.affiliation: Thyroid Cancer Center, Department of Surgery, Gangnam Severance Hospital, Yonsei University College of Medicine, Seoul, Korea.
authors.forename: Yong Sang
authors.initials: YS
authors.lastname: Lee
authors.affiliation: Thyroid Cancer Center, Department of Surgery, Gangnam Severance Hospital, Yonsei University College of Medicine, Seoul, Korea. surghsc@yuhs.ac.
authors.forename: Hang-Seok
authors.initials: HS
authors.lastname: Chang
authors.affiliation: Thyroid Cancer Center, Department of Surgery, Gangnam Severance Hospital, Yonsei University College of Medicine, Seoul, Korea.
authors.forename: Cheong Soo
authors.initials: CS
authors.lastname: Park
mesh_terms: D000293:Adolescent; D000328:Adult; D000368:Aged; D044963:Biopsy, Fine-Needle; D002277:Carcinoma / Q000175:diagnosis* / Q000000981:diagnostic imaging / Q000473:pathology* / Q000601:surgery; D002291:Carcinoma, Papillary; D005188:False Negative Reactions; D005260:Female; D006801:Humans; D008198:Lymph Nodes / Q000000981:diagnostic imaging / Q000473:pathology*; D008207:Lymphatic Metastasis / Q000000981:diagnostic imaging / Q000473:pathology*; D008297:Male; D008875:Middle Aged; D015999:Multivariate Analysis; D011300:Preoperative Care; D012307:Risk Factors; D012680:Sensitivity and Specificity; D013954:Thyroglobulin / Q000378:metabolism; D000077273:Thyroid Cancer, Papillary; D013961:Thyroid Gland / Q000473:pathology*; D013964:Thyroid Neoplasms / Q000175:diagnosis* / Q000000981:diagnostic imaging / Q000473:pathology* / Q000601:surgery; D014057:Tomography, X-Ray Computed; D055815:Young Adult
chemical_list: D013954:Thyroglobulin
keywords: Papillary thyroid carcinoma; metastasis