OBJECTIVETo discuss the selection of the initial surgery extent for differentiated thyroid cancer (DTC) without metastasis.

METHODSThe clinical data of 504 cases with DTC, who accepted the surgical treatment from Jan 1995 to Dec 2004, were analyzed and studied. There were 329 cases without metastasis. The operative extents less than total thyroidectomy were performed on 93 cases (92.1%) with stage T(1), 166 cases (88.3%) with stage T(2), 22 cases (91.7%) with stage T(3) and 12 cases (75.0%) with stage T(4). The recurrence situation after the initial surgery was compared between different T-stage groups and between different surgical extents, total and less than total thyroidectomy.

RESULTSThe recurrence of DTC was found in 37 cases of the follow-up cases (8.9%), including 29 cases without metastasis in the initial surgery. There was no significant difference in the recurrent rate between T(1) and T(2) groups (P>0.05). The significant difference was found in recurrent rate between T(1) and T(3) or T(4) groups, T(2) and T(3) or T(4) groups (P<0.05). No significant difference in the ratio of the initial surgical extent less than total thyroidectomy was found between stage T(1) and T(2) cases without metastasis (P>0.05). The rate of the recurrent laryngeal nerve injury was 1.2%. The transient hypoparathyroidism happened in 2% of the cases, without the permanent hypoparathyroidism.

CONCLUSIONSThe surgical extent less than total thyroidectomy, especially subtotal thyroidectomy, is rational and available to stage T(1) and T(2) cases of DTC without metastasis. It can effectively remove the tumor and avoid postoperative complications. Total thyroidectomy should be performed on stage T(3) and T(4) cases of DTC.