Overall Survival of Papillary Thyroid Carcinoma Patients: A Single-Institution Long-Term Follow-Up of 5897 Patients

Introduction Papillary thyroid carcinoma (PTC) generally shows an excellent prognosis except in cases with aggressive backgrounds or clinicopathological features. Although the cause-specific survival (CSS) of PTC patients has been extensively investigated, the overall survival (OS) of these patients is unclear. We herein investigated both the OS and CSS of a large PTC patient series. Materials and methods We enrolled 5897 PTC patients who underwent initial surgery between 1987 and 2005 (658 males and 5339 females; median age 51 years). Their median postoperative follow-up period was 177 months. Univariate and multivariate analyses for OS and CSS assessed the effects of gender, older age (≥55 years), distant metastasis at diagnosis ( M 1), significant extrathyroid extension, tumor size (cutoffs 2 and 4 cm), large node metastasis ( N ≥ 3 cm), and extranodal tumor extension. Results To date, 387 patients (7%) in this series have died from various causes, including 117 (2%) due to PTC. The 10-, 15-, and 20-year OS rates are 97, 95, and 90%, respectively. Older age and M 1 were important prognostic factors for OS and CSS. Older age was a more significant factor than M 1 for OS and vice versa for CSS. In the older patients, M 1 was a prominent prognostic factor for both OS and CSS. In the young patients, M 1 had less prognostic impact than in the older patients, and the prognostic values of M 1 and N ≥ 3 cm for OS and CSS were identical and similar, respectively. Conclusions The most important prognostic value for OS was patient age, indicating that PTC is generally indolent. However, the control of distant metastasis in older patients remains a future challenge in order to further improve their OS and CSS. PTC of ≥3 cm in young patients should be carefully followed, even in the absence of metastases, and these patients should undergo aggressive therapies for recurrent lesions and metastases.