Impact of adjuvant external irradiation in treatment of locally advanced papillary carcinoma of the thyroid

ABSTRACT

To look for the possible efficacy of external beam irradiation [EBRT] for locally advanced papillary thyroid cancers. Between April 2002 and June 2005, 91 patients with locally advanced papillary thyroid cancers [pathologic stage T4 or N1] were treated with surgical resection. After surgery, 23 patients received postoperative EBRT [12 patients were treated with EBRT+ ablative radioiodine therapy [RAI] and 11 patients received postoperative EBRT only], and 68 patients were treated with RAI alone. The distribution of age, sex, and stage was comparable in both therapeutic groups. The overall survival rates at 2 years were statistically not significantly different between the two groups at 98.1% for the no-EBRT group and 90% for the EBRT group [p = 0.5]. The locoregional control rates at 2 years were significantly different [EBRT 95.2% and no EBRT 67.5%; p = 0.04]. Analysis of the prognostic factors age, sex, stage, and use of radioiodine ablative therapy, indicated these were not significantly variables, except for EBRT. Adjuvant postoperative EBRT did not affect overall survival, but significantly improved locoregional control in patients with locally advanced papillary thyroid cancer [Stage T4 or Lymph node involvement]