Background: The clinical significance of microscopically locoresional-residual differentiated thyroid carcinoma is still an unsolved problem.
Methods: Patients who underwent resectional management for advanced differentiated thyroid carcinoma were divided into complete (n = 58), microscopic (n = 37), macroscopic (n = 14), and distant (n = 22) groups.
Results: Postoperative recurrence was similar in the complete (28%) and microscopic (22%) groups and was significantly lower than that of the macroscopic (57%) and distant (67%) groups. Age, gender, lymph node metastasis, and the residual status (complete and microscopic versus macroscopic and distant) were independent risk factors for recurrence. Postoperative survival of the complete and microscopic groups groups was better than that of the macroscopic and distant groups. Age and the residual status were independent prognostic factors for overall and cause-specific survival.
Conclusions: Postoperative recurrence and survival of patients with microscopic residual cancer were similar to those of patients with complete resection, and macroscopic residual cancer either in locoregional or distant loci was an ominous prognostic sign.