Accuracy of ultrasound for the diagnosis of cervical lymph node metastasis in esophageal cancer: a systematic review and meta-analysis.
BACKGROUND
Esophageal cancer is considered a serious malignancy with respect to its prognosis and mortality rate. Cervical lymph node status is one of the keys to determining prognosis and treatment methods. However, published data vary regarding the accuracy of ultrasound in the diagnosis of cervical lymph node metastasis. We performed a meta-analysis to assess the efficacy of ultrasound for detecting cervical lymph node metastasis in patients with esophageal cancer.


METHODS
The PubMed/MEDLINE, EMBASE, Web of Science, and Cochrane Library databases were searched to identify studies related to cervical lymph node metastasis, and 22 studies comprising 3,513 patients met our inclusion criteria. We used a bivariate meta-analysis following a random effects model to summarize the data. We also explored reasons for statistical heterogeneity using meta-regression, subgroup, and sensitivity analyses. Publication bias was assessed with a Deeks funnel plot.


RESULTS
The area under the receiver operating characteristic curve was 0.97 [95% confidence interval (CI): 0.95-0.98], and the pooled diagnostic odds ratio was 121.00 (95% CI: 47.57-307.79). With cut-off values of 5 mm and >5 mm for cervical lymph node size, the sensitivities and specificities (95% confidence interval) for ultrasound detection of cervical lymph node metastasis were 84% (67-93%) and 93% (90-95%); and 94% (76-98%) and 98% (89-100%), respectively.


CONCLUSIONS
We show for the first time the diagnostic accuracy of ultrasound for predicting cervical lymph node-positive metastasis in esophageal cancer. Our analysis shows that ultrasonography may be an effective and reliable approach to detect cervical lymph node metastasis in esophageal cancer. However, to accommodate heterogeneity, high-quality studies are needed to further verify the efficacy of ultrasound detection.
Department of Cardiothoracic Surgery, the Affiliated Hospital of Chengdu University, Chengdu 610081, China ;
Xue-Feng
XF
Leng
Department of Ultrasound, Sichuan Cancer Hospital, Chengdu 610041, China ;
Yi
Y
Zhu
Department of Cardiothoracic Surgery, the Affiliated Hospital of Chengdu University, Chengdu 610081, China ;
Ge-Ping
GP
Wang
Department of Cardiothoracic Surgery, the Affiliated Hospital of Chengdu University, Chengdu 610081, China ;
Jian
J
Jin
Department of Thoracic Surgery, the First Affiliated Hospital of Guangxi Medical University, Nanning 530021, China ;
Lei
L
Xian
Department of Gastroenterology, the First Affiliated Hospital of Guangxi Medical University, Nanning 530021, China.
Yu-Hong
YH
Zhang
Esophageal cancer; cervical lymph node; ultrasonography