The prognostic value of regional lymph node metastases in patients of Guangdong Province, China with differentiated thyroid cancer

Abstract

Although the prognostic value of nodal metastases in differentiated thyroid cancer remains controversial, it is of interest to evaluate and understand the different characteristics of predictive outcomes.A multicenter retrospective study was conducted in 215 untreated patients with differentiated thyroid cancer from July 1997 to July 2015 in 4 medical centers of Guangdong Province. A total of 107 patients with nodal metastases (group A) were compared to 108 patients without metastases (group B). The 5-year disease-free survival (DFS), overall survival (OS), and postoperative complications in both groups were calculated. Variables predictive of DFS and OS were evaluated in group A.The group A had lower 5-year DFS (69.16%, 11 months) and shorter median time of recurrence than those in group B (87.96%, 8.5 months, respectively, P < 0.001). The incidence of temporary hypoparathyroidism in group A is lower; whereas higher incidence of temporary unilateral vocal cord palsy, permanent hypoparathyroidism, permanent unilateral vocal cord palsy, and bilateral vocal cord palsy in group A were observed. Both univariate and multivariate analyses in group A revealed that age, pathological tumor node metastasis (pTNM) stage, and histology were related to DFS (P < 0.05); while pTNM stage and histology were related to OS only in univariate analyses.Positive nodal metastases have significant prognostic value in patients with differentiated thyroid cancer in Guangdong, China and primarily reduce DFS. Moreover, patients with positive nodal metastases who are >45 years and have higher pTNM stage or follicular histology tend to have poor prognosis. Selective lymph node dissection with appropriate postoperative treatment and frequent follow-up should be accorded to these vulnerable groups of patients.

The Relationship of Age and Clinicopathologic Pattern to the Aggressiveness of Thyroid Cancer

“…The dose of radioiodine therapy for post operative patients with welldifferentiated thyroid cancer is controversial. Some recommended low-dose of I131 ablation (30,50 or 75 mCi of I131) But we need to give repeated doses for ablation, the cumulative ablation rate was 99% [32]. Higher ablative treatments ranging from 100 -150 mCi should be used for older high-risk patients particularly those known to have an incomplete resection of the primary tumor, and invasive primary tumor or metastasis with a success rate of 84% [33].…”