Surgery 112(6): 1139-1147, 1992.
Hay ID, Grant CS, van Heerden JA, et al.
The study aims were to characterize patients with papillary thyroid microcarcinoma and to provide data on outcome after surgical therapy.
Five hundred thirty-five patients with papillary microcarcinoma had initial treatment at Mayo Clinic from 1940 to 1989. Follow-up extended to 48 years. Median follow-up time for 400 survivors was 16 years. Recurrence and mortality details were derived from a computerized cancer database.
Median tumor size was 8 mm. Ninety-nine percent of tumors were histologic grade 1; 98% were not locally invasive. Thirty-two percent of patients had nodal metastases at examination. TNM stages were I in 485 patients (91%), III in 49 patients (9%), and IV in one patient (0.2%). Ninety-one percent of patients underwent bilateral lobar resection. Tumor resection was incomplete in three cases (0.6%). Radioiodine remnant ablation was performed in 55 patients (10%). All-causes survival did not differ from expected; two patients (0.4%) died of papillary microcarcinoma. Twenty-year tumor recurrence rate was 6%. Higher recurrence rates were seen either with node-positive patients (p < 0.0001) or after unilateral lobectomy (p < 0.0001). Recurrence rates did not appear to be significantly altered by total thyroidectomy (p = 0.44) or radioiodine remnant ablation in node-positive patients (p = 0.99).
These results reaffirm that papillary microcarcinoma has an excellent prognosis if managed initially by bilateral lobar resection. Routine radioiodine remnant ablation is not indicated.
Rheinische Friedrich- Wilhelms- Universität Bonn