Follicular and Hurthle cell carcinoma of the thyroid in iodine-sufficient area: retrospective analysis of Korean multicenter data.
OBJECTIVE
Follicular thyroid carcinoma (FTC) and Hurthle cell carcinoma (HCC) of the thyroid are relatively uncommon thyroid malignancies in iodine-sufficient areas. In this study we evaluated the clinical behavior, prognostic factors and treatment outcomes of FTC and HCC in Korea.


METHODS
This multicenter study included 483 patients with FTC and 80 patients with HCC who underwent an initial surgery between 1995 and 2006 in one of the four tertiary referral hospitals in Korea. We evaluated clinicopathological factors associated with distant metastases and recurrence during a median of 6 years of follow-up.


RESULTS
HCC patients were significantly older (49 years vs. 43 years; p < 0.001) and had more lymphovascular invasions (22% vs. 14%; p = 0.03) compared with FTC patients. Distant metastases were confirmed in 40 patients (8%) in the FTC group and in two patients (3%) in the HCC group (p = 0.07). Distant metastases were significantly associated with older age, widely invasive cancer and extrathyroidal invasion. Only 14 patients (3%) had recurrent disease and there was no significant difference between FTC and HCC groups (p = 0.38). Recurrence was associated with larger tumor size and cervical lymph node metastasis.


CONCLUSIONS
HCC patients were older and had more lymphovascular invasions than FTC patients. However, FTC and HCC patients had similar initial clinicopathological features. Older age, wide invasiveness and extrathyroidal invasion were independent risk factors for predicting distant metastases in FTC and HCC patients.
Department of Internal Medicine, Asan Medical Center, University of Ulsan College of Medicine, Seoul, Korea.
Won Gu
WG
Kim
Department of Internal Medicine, Asan Medical Center, University of Ulsan College of Medicine, Seoul, Korea.
Tae Yong
TY
Kim
Department of Internal Medicine, Seoul National University College of Medicine, Seoul, Korea.
Tae Hyuk
TH
Kim
Department of Internal Medicine, Samsung Medical Center, Sungkyunkwan University School of Medicine, Seoul, Korea.
Hye Won
HW
Jang
Department of Internal Medicine, Chungnam National University School of Medicine, Daejeon, Korea.
Young Suk
YS
Jo
Department of Internal Medicine, Seoul National University College of Medicine, Seoul, Korea.
Young Joo
YJ
Park
Department of Internal Medicine, Samsung Medical Center, Sungkyunkwan University School of Medicine, Seoul, Korea.
Sun Wook
SW
Kim
Department of Internal Medicine, Asan Medical Center, University of Ulsan College of Medicine, Seoul, Korea.
Won Bae
WB
Kim
Department of Internal Medicine, Chungnam National University School of Medicine, Daejeon, Korea.
Minho
M
Shong
Department of Internal Medicine, Seoul National University College of Medicine, Seoul, Korea.
Do Joon
DJ
Park
Department of Internal Medicine, Samsung Medical Center, Sungkyunkwan University School of Medicine, Seoul, Korea.
Jae Hoon
JH
Chung
Department of Internal Medicine, Asan Medical Center, University of Ulsan College of Medicine, Seoul, Korea.
Young Kee
YK
Shong
Department of Internal Medicine, Chung-Ang University College of Medicine, Seoul, Korea.
Bo Youn
BY
Cho
D018263:Adenocarcinoma, Follicular / Q000453:epidemiology* / Q000556:secondary / Q000601:surgery; D018249:Adenoma, Oxyphilic; D000328:Adult; D000367:Age Factors; D004032:Diet; D005260:Female; D006801:Humans; D007455:Iodine; D008207:Lymphatic Metastasis; D008297:Male; D008875:Middle Aged; D009364:Neoplasm Recurrence, Local; D009752:Nutritional Status; D056910:Republic of Korea / Q000453:epidemiology; D012189:Retrospective Studies; D012307:Risk Factors; D062606:Tertiary Care Centers; D013964:Thyroid Neoplasms / Q000453:epidemiology* / Q000473:pathology / Q000601:surgery; D013965:Thyroidectomy; D013997:Time Factors; D016896:Treatment Outcome
D007455:Iodine
Distant metastases; Follicular adenocarcinoma; Hurthle cell thyroid cancer; Iodine; Prognosis