Effectiveness and Safety of Levothyroxine Tablets Combined with Iodine-131 in the Treatment of Thyroid Cancer

Abstract

Objective. To explore the effectiveness of levothyroxine tablets combined with iodine-131 in thyroid cancer patients after radical thyroidectomy and the effect on their serum thyroglobulin (Tg) and thyroglobulin antibody (TgAb) levels. Methods. A total of 70 thyroid cancer patients receiving radical thyroidectomy in our hospital from July 2015 to April 2016 were recruited and were assigned via different treatment methods (1 : 1) to receive either levothyroxine tablets (observation group) or levothyroxine tablets plus iodine-131 (control group). Outcome measures included treatment efficiency, 1, 3, and 5-year recurrence and metastasis, serum Tg and TgAb levels, postoperative survival, and adverse reactions. Results. The total effective rate of treatment in the control group was significantly higher than that in the observation group ( P < 0.05 ). There was no significant difference in cancer recurrence and metastasis rate between the two groups one year postoperatively ( P > 0.05 ). The rate of cancer recurrence and metastasis in the control group was significantly lower than that in the observation group 3 and 5 years after surgery ( P < 0.05 ). Before treatment, there was no significant difference in serum Tg and TgAb levels between the two groups ( P > 0.05 ). After treatment, serum Tg and TgAb levels decreased in both groups, with lower results in the control group ( P < 0.05 ). There was no significant difference in the 1 and 3-year survival rates between the two groups ( P > 0.05 ). The 5-year survival rate in the control group was significantly higher than that in the observation group ( P < 0.05 ). There was no significant difference in adverse reactions between the two groups ( P > 0.05 ). Conclusion. Levothyroxine tablets combined with iodine-131 for thyroid cancer patients undergoing radical thyroidectomy effectively could improve the treatment efficiency, reduce the risk of cancer recurrence and metastasis after surgery, lower the serum Tg and TgAb levels of patients, and prolong the survival of patients, with a high safety profile. Further trials are, however, required prior to clinical promotion.

Efficacy and safety of postoperative levothyroxine sodium tablets for improving serum thyroid hormone levels and tumor marker levels in patients with thyroid tumors

“… 19 The other seven studies evaluated the efficacy of levothyroxine tablets against combined therapies. Two included studies compared levothyroxine monotherapy with a combination of levothyroxine and iodine-131, 15 , 16 whereas five other studies evaluated levothyroxine monotherapy against LT4/LT3 combination therapy. 26-30 Of the seven studies, two were of China origin, 15 , 16 while the rest were from Australia, 29 Russia, 30 Brazil, 28 America, 26 and Spain.…”

“…Two included studies compared levothyroxine monotherapy with a combination of levothyroxine and iodine-131, 15 , 16 whereas five other studies evaluated levothyroxine monotherapy against LT4/LT3 combination therapy. 26-30 Of the seven studies, two were of China origin, 15 , 16 while the rest were from Australia, 29 Russia, 30 Brazil, 28 America, 26 and Spain. 27 Regarding patient age, most studies included adults between 18 and 78 years old, except for one study that included newborns aged between 3 to 5 days old.…”

“…Regarding the clinical safety and efficacy of levothyroxine sodium tablets in improving levels, two studies investigated the effect of sodium levothyroxine tablet monotherapy compared with the levothyroxine tablet combined iodine (131). 15 , 16 Based on their findings, the treatment regimen of sodium levothyroxine tablets combined with iodine 131 effectively reduced the serum Tg levels implying its effectiveness over levothyroxine tablet monotherapy. Pooled-meta-analysis results showed a statistically significant difference between LT4 tablet monotherapy and the combined regimen of L-T4 and iodine-131 (SMD= 3.61, 95% CI= [2.89, 4.33], p < 0.00001) ( Figure 9 ).…”