Operative strategy in follicular thyroid cancer.
OBJECTIVE
Surgery is the main treatment for most thyroid cancers. However, the indications for subtotal or radical thyroidectomy in cases of follicular thyroid cancer remain controversial. This study examined the indications for subtotal thyroidectomy or radical total thyroidectomy in patients with follicular cancer.


METHODS
A total of 196 cases of follicular cancer diagnosed among 1,545 thyroid cancer cases between 1960 and 2000 at National Taiwan University Hospital (NTUH) were included in this study. Diagnosis of follicular cancer was based on the findings of pathologic examination. All surgeries were performed in the Department of Surgery at NTUH. The average period of postoperative follow-up was 11.7 years. Subtotal thyroidectomy was defined as thyroid resection performed on not more than two-thirds of the whole lobe. Radical thyroidectomy was defined as total removal of the thyroid plus cervical lymph node removal if surgical examination revealed malignancy. Local recurrence was defined as tumor reappearance in soft tissue in the neck or cervical lymph node after initial treatment. Distal metastasis was also surveyed from medical records. Patients were classified into three groups according to the size of the surgical specimen as less than 3 cm in diameter, 3 to 5 cm, and more than 5 cm.


RESULTS
Between 1960 and 2000, the percentage of follicular cancer patients undergoing follicular cancer surgery decreased from 22.0 to 7.7%, while papillary cancer surgery increased from 65.5 to 87.1%. This change was associated with the addition of iodine to table salt island-wide from 1967. The change in percentage of surgically treated cases was greater between 1991 and 2000. Subtotal thyroidectomy was performed in 56 cases and radical thyroidectomy was performed in 140 cases during the study period. None of the 63 cases with a tumor diameter of less than 3 cm undergoing either radical or subtotal thyroidectomy had local recurrence during a mean follow-up of 11.7 years. However, six of those cases (9.5%) had distant metastasis.


CONCLUSIONS
For follicular cancers of less than 3 cm in diameter, subtotal thyroidectomy instead of radical thyroidectomy may be considered, but close follow-up is necessary.
Wang
Ming-Yung
MY
Department of Surgery, National Taiwan University Hospital, 7 Chung-Shan South Road, Taipei, Taiwan.
Lin
Ming-Tsan
MT
Liaw
Koung-Yi
KY
D018263:Adenocarcinoma, Follicular / Q000473:pathology / Q000601:surgery*; D005260:Female; D006801:Humans; D008297:Male; D008875:Middle Aged; D009362:Neoplasm Metastasis; D009364:Neoplasm Recurrence, Local; D013964:Thyroid Neoplasms / Q000473:pathology / Q000601:surgery*; D013965:Thyroidectomy / Q000379:methods*