Improvement of lymph node recurrence rate, but not distant recurrence and carcinoma death rates, in patients with papillary thyroid carcinoma after disease-free survival for 5 years.

In this study, we investigated the difference in lymph node-recurrence free survival (LN-RFS), distant recurrence-free survival (DRFS), and cause-specific survival (CSS) between patients with papillary thyroid carcinoma (PTC) in the entire group (Group I) and those with lymph node- and distant-recurrence-free survival (DFS) for 5 years after initial surgery (Group II). The LN-RFS of patients with all risk classifications in Group II was significantly better than that of those in Group I. The LN-RFS of intermediate-risk patients in Group II did not differ from that of low-risk patients in Group I, but LN-RFS of high-risk patients in Group II was significantly poorer than intermediate- and low-risk patients in Group I. DRFS and CSS of Group II patients did not significantly differ from those of Group I patients in the same risk classification. DRFS and CSS of high-risk patients in Group II were significantly poorer than those of intermediate- and low-risk patients in Group I, and those of intermediate-risk patients in Group II were also significantly poorer than those of low-risk patients in Group I. Taken together, the lymph node recurrence rate, but not distant recurrence and carcinoma death rates, of patients in all classifications significantly improved after DFS for 5 years. However, careful follow-up for lymph node recurrence of high-risk patients and for distant recurrence of intermediate- and high-risk patients is necessary thereafter.