title: Diagnosis of Metastasis to the Thyroid Gland: Comparison of Core-Needle Biopsy and Fine-Needle Aspiration.
abstract: OBJECTIVE
  Early detection and diagnosis of metastasis to the thyroid gland is important. This study aims to evaluate the clinical value of core-needle biopsy (CNB) by comparing the results of CNB and fine-needle aspiration (FNA) in patients with clinically suspected metastasis to the thyroid gland.
  
  
  METHODS
  Case series with chart review.
  
  
  METHODS
  Tertiary referral practice.
  
  
  METHODS
  Fifty-two thyroid nodules from 52 patients with clinically suspected metastasis to the thyroid gland (mean age, 62.8 years).
  
  
  METHODS
  Of these 52 patients, FNA was initially used in 41 patients and CNB in 20 patients (11 patients as the initial approach and 9 patients after inconclusive FNA results). Ultrasound features of metastasis to the thyroid gland were evaluated. The diagnostic performance, repeated diagnostic examination rate, and diagnostic surgery rate were evaluated for FNA and CNB.
  
  
  RESULTS
  Among these 52 patients, 46 were diagnosed with thyroid metastases and 6 were diagnosed with primary thyroid cancer. Common ultrasound features were an ovoid to round shape (58.7%), ill-defined margin (56.5%), hypoechogenicity (65.2%), and no calcifications (87.0%). Core-needle biopsy achieved a significantly higher sensitivity than FNA (100.0% vs 58.6%, P = .008) without any false-negative results. Both the repeated diagnostic examination rate and the diagnostic surgery rate were significantly lower in CNB than in FNA (5.0% vs 46.3%, P = .001, and 5.0% vs 34.1%, P = .013, respectively).
  
  
  CONCLUSIONS
  In cases of known rare primary malignancy, nontypical ultrasound features of primary thyroid malignancy, and need for an additional immunohistochemical analysis, CNB may be primarily considered.
authors.affiliation: Department of Radiology and the Research Institute of Radiology, University of Ulsan College of Medicine, Asan Medical Center, Songpa-Gu, Seoul, Korea.
authors.forename: Sang Hyun
authors.initials: SH
authors.lastname: Choi
authors.affiliation: Department of Radiology and the Research Institute of Radiology, University of Ulsan College of Medicine, Asan Medical Center, Songpa-Gu, Seoul, Korea radbaek@naver.com.
authors.forename: Jung Hwan
authors.initials: JH
authors.lastname: Baek
authors.affiliation: Department of Radiology, Ajou University School of Medicine, Wonchon-Dong, Yeongtong-Gu, Suwon, Korea.
authors.forename: Eun Ju
authors.initials: EJ
authors.lastname: Ha
authors.affiliation: Department of Radiology and the Research Institute of Radiology, University of Ulsan College of Medicine, Asan Medical Center, Songpa-Gu, Seoul, Korea.
authors.forename: Young Jun
authors.initials: YJ
authors.lastname: Choi
authors.affiliation: Department of Pathology, University of Ulsan College of Medicine, Asan Medical Center, Songpa-Gu, Seoul, Korea.
authors.forename: Dong Eun
authors.initials: DE
authors.lastname: Song
authors.affiliation: Department of Radiology, Chung-Ang University College of Medicine, Dongjak-gu, Seoul, Korea.
authors.forename: Jae Kyun
authors.initials: JK
authors.lastname: Kim
authors.affiliation: Department of Surgery, University of Ulsan College of Medicine, Asan Medical Center, Songpa-Gu, Seoul, Korea.
authors.forename: Ki-Wook
authors.initials: KW
authors.lastname: Chung
authors.affiliation: Department of Endocrinology and Metabolism, University of Ulsan College of Medicine, Asan Medical Center, Songpa-Gu, Seoul, Korea.
authors.forename: Tae Yong
authors.initials: TY
authors.lastname: Kim
authors.affiliation: Department of Radiology and the Research Institute of Radiology, University of Ulsan College of Medicine, Asan Medical Center, Songpa-Gu, Seoul, Korea.
authors.forename: Jeong Hyun
authors.initials: JH
authors.lastname: Lee
mesh_terms: D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D044963:Biopsy, Fine-Needle; D062005:Biopsy, Large-Core Needle; D055088:Early Detection of Cancer; D005260:Female; D006801:Humans; D008297:Male; D008875:Middle Aged; D012189:Retrospective Studies; D012680:Sensitivity and Specificity; D013964:Thyroid Neoplasms / Q000000981:diagnostic imaging / Q000556:secondary* / Q000601:surgery; D014463:Ultrasonography
keywords: biopsy; fine needle; large-core needle; metastasis; thyroid; ultrasound