SPECT/CT in assessment of incidence and impact factors of lymph nodes metastasis of low-risk papillary thyroid
10.13929/j.1003-3289.201902150
- Author:
Minmin ANG
1
Author Information
1. Department of Nuclear Medicine, Zhengzhou University People's Hospital, Henan Provincial Hospital
- Publication Type:Journal Article
- Keywords:
Iodine radioisotopes;
Lymph nodes;
Neoplasm metastasis;
Radionuclide imaging;
Thyroid neoplasms
- From:
Chinese Journal of Medical Imaging Technology
2019;35(10):1477-1481
- CountryChina
- Language:Chinese
-
Abstract:
Objective: To evaluate the incidence and probable impact factors of metastatic lymph nodes on SPECT/CT in patients with low-risk thyroid papillary cancer (PTC) after surgical operation and 131I treatment. Methods: Data of 409 patients with low risk PTC based on 2015 edition of American Thyroid Association guidelines after surgical operation and before 131I treatment were analyzed. Whole body scintigraphy(WBS) and SPECT/CT were performed 5 days after 131I treatment. According to imaging results and follow-up data, the presence of metastatic lymph nodes on SPECT/CT was estimated. Clinical data of patients with and without metastatic lymph nodes were compared, the impact factors of metastatic lymph nodes on SPECT/CT were analyzed, and optimal threshold value of lymph node metastasis was predicted with ROC curve. Results: SPECT/CT showed metastatic lymph nodes in 91 patients with low risk PTC after 131I treatment, with an incidence of 22.25% (91/409). Univariate analysis showed that the tumor size, stimulated thyroglobulin (sTg) and T stage were impact factors for the existence of metastatic lymph nodes (all P<0.05). Logistic regression showed that sTg was an independent predictor for assessment of metastatic lymph nodes in patients with low-risk PTC. ROC curve analysis showed that the optimal cutoff of sTg in predicting metastatic lymph nodes was 4.01 ng/ml, with sensitivity of 87.3% and specificity of 60.1%. Conclusion: The incidence of metastatic lymph nodes on SPECT/CT is relative high in patients with low risk PTC after surgical operation and 131I treatment. The large tumor and high level of sTg are the impactfactors of the existence of metastatic lymph nodes, and the latter is an important index to predict the existence of metastatic lymph nodes.
