Relationship between the initial change of thyroglobulin and outcome in differentiated thyroid carcinoma patients with pulmonary metastases after 131I treatment

Abstract

Objective To investigate the relationship between the initial change of thyroglobulin (Tg) and clinical outcome in differentiated thyroid carcinoma (DTC) patients with pulmonary metastases after 131I treatment. Methods A total of 69 DTC patients with pulmonary metastases from January 2010 to December 2015 were retrospectively analyzed. Patients were divided into 3 groups according to the variation of Tg: group Ⅰ(Tg declined ≥ 50%), group Ⅱ (Tg declined<50% or Tg increased<10%), and group Ⅲ (Tg increased ≥10%). The follow-up time was (49.2 ± 9.3) months. Clinical outcomes were divided into remission, stable disease and progressive disease according to the serum test and imaging results. Results The percentage of group Ⅰ, Ⅱ, Ⅲ patients was 44.9% (31/69), 40.6% (28/69), and 14.5% (10/69) respectively. Results of follow-up showed 19.4% (6/31) patients achieved remission and 80.6% (25/31) had stable disease in group Ⅰ. There were 10.7% (3/28) patients with remission, 60.7% (17/28) with stable disease and 28.6% (8/28) with progression disease in group Ⅱ. All patients showed progressive disease in group Ⅲ. The clinical outcome was related to the variation of Tg after 131I treatment (P<0.01). Conclusions Initial Tg after 131I treatment could be a predictor to the outcome of patients. The increased Tg level indicates a high possibility of 131I refractory disease. Key words: Thyroid neoplasms; Thyroglobulin; Iodine radioisotopes; Lung metastasis