Abstract: In this paper, the application value of the enhancement feature and quantitative parameters of contrast-enhanced ultrasound in the identification for papillary thyroid carcinoma and benign nodules were explored, as well as their relationship with biological behaviors of the thyroid carcinoma. There were 68 patients with papillary thyroid carcinoma who were selected as the study group, and 65 patients with benign thyroid nodules who were selected as the control group. The contrast enhancement features of the study group were mainly low enhancement in the early stage or in the whole stage, and in the control group was mainly equal or high enhancement. There was a statistically significant difference in enhancement characteristics of contrast-enhanced ultrasound between the two groups (P<0.05). The PI of the study group was lower than that of the control group, and the TTP was longer than the control group (P<0.05). The area under the curve (AUC) of the combined diagnosis for thyroid micropapillary carcinoma by contrast-enhanced ultrasound, PI, and TTP was 0.896, which was greater than that of each index alone. Tumor diameter, extraglandular invasion and lymph node metastasis of thyroid micropapillary carcinoma were negatively correlated with the enhanced degree of contrast-enhanced ultrasound and PI, and positively correlated with TTP. The degree of 422 differentiation was positively correlated with the enhanced degree of contrast-enhanced ultrasound and PI, and negatively correlated with TTP (P<0.05). In conclusion, contrast-enhanced ultrasound features and quantitative parameters (PI and TTP) have high diagnostic efficiency in the diagnosis of thyroid micropapillary carcinoma, and has a close correlation with the biological behavior of cancer.

Key words: thyroid micropapillary carcinoma, benign thyroid nodules, contrast-enhanced ultrasound, differential diagnosis, tumor biological behavior