Abstract:
Objective To investigate the value of serum midkine (MK) and galectine-3 (Gal-3) in the differential diagnosis of benign and malignant thyroid nodules, and to analyze the ability of serum MK and Gal-3 to evaluate metastases before the first 131I treatment in patients with differentiated thyroid cancer (DTC) after thyroidectomy.
Methods ①Data on benign and malignant thyroid nodule differential diagnosis were collected from November 2016 to November 2017 in the First Hospital of Shanxi Medical University. In general surgery, 41 cases (11 males and 30 females, aged 29−73 (48.61±11.59) years) of surgical treatment of thyroid nodules in patients with preoperative blood specimens were determined. The patients were divided according to the result of pathology as follows: malignant group (23 cases) and benign group (18 cases). A total of 32 healthy subjects served as controls. One-way ANOVA was used to analyze whether preoperative serum MK and Gal-3 were different in benign and malignant thyroid nodules. Receiver operating characteristic curve was drawn to study the diagnostic value of the two in thyroid nodules. ②From November 2016 to November 2017, 51 patients (12 males and 39 females, aged 25−72 (44.41±10.21) years) with DTC before the first 131I treatment in the Nuclear Medicine Department of the First Hospital of Shanxi Medical University participated in the evaluation of postoperative metastasis. All patients underwent 131I treatment two times, and the whole body iodine scan was performed 5−7 days after each treatment. According to the results and other examination results (ultrasound, CT, PET/CT), the lymph node and/or lung metastasis was judged. Serum was collected before the first iodine treatment. The differences in MK and Gal-3 between groups were compared using two-sample t-test. Pearson test was used to analyze the correlation between serum MK and Gal-3.before the first iodine treatment. The differences in MK and Gal-3 between groups were compared using two-sample t-test. Pearson test was used to analyze the correlation between serum MK and Gal-3.
Results ①Pre-surgical MK and Gal-3 levels were significantly higher in patients with malignant thyroid nodule than those in benign cases and in controls (F=48.40, 5.08, both P<0.05). The ROC curve analysis determined the optimal value of MK and Gal-3 for differential diagnosis between malignant and benign thyroid nodules. The diagnostic power of MK was the highest at 318.87 pg/mL, with an area under the ROC curve (AUC) of 0.91(95%CI: 0.81~0.99), specificity of 78.1%, and sensibility of 88.5%. The diagnostic power of Gal-3 was the highest at 1.61 ng/mL, with AUC of 0.72(95%CI: 0.57~0.86), specificity of 70.4%, and sensibility of 69.8%. ②The patients were grouped according to the presence of lymph node and bone and/or lung metastasis into metastasis positive group (8 cases) and negative group (43 cases). Thyroglobulin, MK(A), and Gal-3(A) in the positive group were significantly higher than those in the negative group (t=−4.86, −4.01, −2.89, all P<0.05). MK (r=0.67, P<0.05) and Gal-3 (r=0.84, P<0.05) were significantly correlated in pre-surgical and pre-131I-ablative.
Conclusions Serum MK and Gal-3 can be used for the differential diagnosis of benign and malignant thyroid nodules and to evaluate whether metastasis is present in patients with DTC before 131I treatment.