Clinical value of color Doppler ultrasound combined with serum tumor markers for the diagnosis of medullary thyroid carcinoma

The present study aimed to explore the clinical value of color Doppler ultrasound combined with serum tumor markers, including calcitonin (CT) and carcinoembryonic antigen (CEA), for the diagnosis of medullary thyroid carcinoma (MTC). A total of 39 patients with MTC (MTC group), 50 patients with papillary thyroid carcinoma (PTC) (PTC group) and 30 patients with thyroid adenoma (benign control group) were enrolled in the present study. The patients were hospitalized at the Affiliated Hospital of Qingdao University from January 2012 to December 2018 and were diagnosed through surgical procedures and pathology laboratory results. The ultrasound results, as well as serum CT and CEA results, were collected and analyzed. A significant difference was observed between the MTC and PTC groups in regards to morphology, margin, aspect ratio, calcification, internal blood flow and lymph node metastasis (all P<0.01). There was also a significant difference between the MTC and benign control group in regards to internal echo, calcification, internal blood flow and lymph node metastasis (all P<0.01). In addition, the levels of serum CT and CEA in the MTC group were significantly higher than those in the PTC and the benign control groups (both P<0.01). For patients with MTC, the levels of serum CT and CEA were significantly associated with maximum tumor diameter, lymph node metastasis and the patient state after treatment (all P<0.01). Furthermore, the sensitivities of ultrasound, serum CT and CEA for the diagnosis of MTC were 76.92, 74.36 and 68.23%, respectively. The value for the combination of the three markers (94.87%) was significantly higher compared with the sensitivity value of each separate marker (all P<0.05). In conclusion, color Doppler ultrasound combined with detecting the levels of serum tumor markers (CT and CEA) significantly improved the diagnostic efficiency for MTC, which could be useful for the clinical diagnosis and treatment of MTC.