The Role of Core Needle Biopsy and Its Impact on Surgical Management in Patients with Medullary Thyroid Cancer: Clinical Experience at 3 Medical Institutions.
OBJECTIVE
Medullary thyroid carcinoma is an uncommon malignancy that is challenging to diagnose. Our aim was to present our experience using core needle biopsy for the diagnosis of medullary thyroid carcinoma compared with fine-needle aspiration.


METHODS
Between January 2000 and March 2012, 202 thyroid nodules in 191 patients were diagnosed as medullary thyroid cancer by using sonography-guided fine-needle aspiration, core needle biopsy, or surgery. One hundred eighty-three thyroid nodules in 172 patients were included on the basis of the final diagnosis. We evaluated the sensitivity and positive predictive value of fine-needle aspiration and core needle biopsy for the diagnosis of medullary thyroid cancer. We compared the rate of a delayed diagnosis, a diagnostic surgery, and surgery with an incorrect diagnosis for fine-needle aspiration and core needle biopsy and investigated the factors related to the fine-needle aspiration misdiagnosis of medullary thyroid cancer.


RESULTS
Fine-needle aspiration showed 43.8% sensitivity and 85.1% positive predictive value for the diagnosis of medullary thyroid cancer; 25.7% (44/171) of patients had a delayed diagnosis, while 18.7% (32/171) underwent an operation for accurate diagnosis, and 20.5% (35/171) underwent an operation with an incorrect diagnosis. Core needle biopsy achieved 100% sensitivity and positive predictive value without a delay in diagnosis (0/22), the need for a diagnostic operation (0/22), or an operation for an incorrect diagnosis (0/22). A calcitonin level of <100 pg/mL was the only significant factor for predicting the fine-needle aspiration misdiagnosis of medullary thyroid cancer (P = .034).


CONCLUSIONS
Core needle biopsy showed a superior sensitivity and positive predictive value to fine-needle aspiration and could optimize the surgical management in patients with medullary thyroid cancer. Because the ability of fine-needle aspiration to diagnose medullary thyroid cancer significantly decreases in patients with serum calcitonin levels of <100 pg/mL, core needle biopsy could be indicated for these patients to optimize their surgical management.
From the Department of Radiology and the Research Institute of Radiology (E.J.H., J.H.B) Department of Radiology (E.J.H.), Ajou University School of Medicine, Suwon, Korea.
E J
EJ
Ha
From the Department of Radiology and the Research Institute of Radiology (E.J.H., J.H.B) radbaek@naver.com.
J H
JH
Baek
Department of Radiology (D.G.N.), Human Medical Imaging and Intervention Center, Seoul, Korea Healthcare System Gangnam Center (D.G.N.), Seoul National University Hospital, Seoul, Korea.
D G
DG
Na
Departments of Radiology (J.-h.K.).
J-h
JH
Kim
Department of Radiology (J.K.K.), Chung-Ang University College of Medicine, Seoul, Korea.
J K
JK
Kim
Pathology (H.S.M.).
H S
HS
Min
Departments of Pathology (D.E.S.).
D E
DE
Song
Surgery (K.E.L.), Seoul National University Hospital, Seoul National University College of Medicine, Seoul, Korea.
K E
KE
Lee
Metabolism and Endocrinology (Y.K.S.), University of Ulsan College of Medicine, Asan Medical Center, Seoul, Korea.
Y K
YK
Shong
D000328:Adult; D000368:Aged; D044963:Biopsy, Fine-Needle; D062005:Biopsy, Large-Core Needle; D018278:Carcinoma, Neuroendocrine / Q000175:diagnosis*; D003951:Diagnostic Errors; D005260:Female; D006801:Humans; D008297:Male; D008875:Middle Aged; D012680:Sensitivity and Specificity; D013964:Thyroid Neoplasms / Q000175:diagnosis*; D016606:Thyroid Nodule / Q000473:pathology