The value of contrast-enhanced ultrasound in differential diagnosis of cervical tuberculous lymphadenitis and lymph nodes metastasis in nasopharyngeal carcinoma

Abstract

Objective To analyze the characteristics of contrast-enhanced ultrasound in cervical tuberculous lymphadenitis (CTBL) and lymph nodes metastasis of nasopharyngeal carcinoma (NPC), and to investigate the value of CEUS in differential diagnosis. Methods The images of 61 cases of CTBL and 48 cases with metastatic lymph nodes in patients with NPC, which confirmed by histopathology in Hangzhou Red Cross Hospital during Jul 2013 to Aug 2017, were retrospectively analyzed. The location, shape, hilum, calcification, necrosis, blood flow and the pattern of contrast enhancement were recorded. The different characteristics were compared by χ2 test. Results U1trasonographic features specific to CTBL were calcifications, and microcalcifications were the ultrasound features of lymph nodes metastasis in NPC. There were statistically significant difference of calcification between two groups (P 0.05). Most of the 61 cervical tuberculous lymphadenitis were found at levelⅢ,ⅣandⅡ(39.3%, 31.1% and 14.8%). Most of the 48 lymph nodes metastasis of nasopharyngeal carcinoma were found at levelⅡ,ⅤandⅢ (45.8%, 29.2% and 12.5%). There were statistically significant difference of the location between two groups (χ2=32.125, P<0.05). According to the thickness of rim, there were three forms of enhancements: thick rim enhancements, thin rim enhancements and no rim enhancement. The thick rim enhancements was more common in the CTBL (39/54, 72.2%), while more metastatic lymph nodes of NPC showed the thin rim enhancements (26/38, 68.4%). There were statistically significant difference between two groups (χ2=25.171, P<0.05). Conclusions Combined with conventional ultrasound, contrast-enhanced ultrasound can provide valuable information of lymph node blood flow in the enhanced mode further, which can help to identify the tuberculous lymphadenitis and lymph nodes metastasis of nasopharyngeal carcinoma. Key words: Cervical tuberculous lymphadenitis; Nasopharyngeal carcinoma; Lymph nodes metastasis; Contrast-enhanced ultrasound; Differential diagnosis