Prognosis and prognostic factors of patients with papillary thyroid carcinoma requiring resection of recurrent laryngeal nerve due to carcinoma extension.

The recurrent laryngeal nerve (RN) is one of the most common organs to which papillary thyroid carcinoma (PTC) extends. However, the prognosis and prognostic factors for patients with PTC extending to the RN remain unclear. In this study, we investigated this issue in 298 patients who underwent initial and locally curative surgery for PTC requiring RN resection due to carcinoma extension. Preoperative vocal cord paralysis was detected in 179 patients (60.1%), and directly linked to significant extension to other organs, large tumor size, and advanced age. However, it did not have a significant prognostic impact on uni- or multivariate analyses. On multivariate analysis, independent prognostic factors were large node metastasis and advanced age for lymph node recurrence, significant extension to other organs for distant recurrence, and significant extension to other organs, large node metastasis, extranodal tumor extension, and advanced age for carcinoma death, respectively. Most prognostic factors identified in the entire series of patients also had a strong prognostic impact on the subset of patients requiring RN resection, together with significant extension to other organs. Preoperative vocal cord paralysis reflected the aggressive characteristic of PTC to some extent, but did not have a significant prognostic value.