Number of Lymph Node Metastases Determined by Presurgical Ultrasound and Endoscopic Ultrasound Is Related to Prognosis in Patients With Esophageal Carcinoma

Abstract
To analyze the impact on prognosis of the number of lymph node metastases detected by ultrasound and endoscopic ultrasound in patients with esophageal carcinoma. Ultrasound and endoscopic ultrasound are useful for diagnosing tumor depth and lymph node metastasis in patients with esophageal carcinoma. However, the clinical significance of the number of lymph node metastases before surgery has not been elucidated. The authors evaluated lymph node metastases using preoperative ultrasound and endoscopic ultrasound in 329 consecutive patients who underwent esophagectomy with lymphadenectomy. TNM classification and one-to-one comparison of lymph node metastasis was performed between the preoperative and histologic diagnosis. The number of lymph node metastases was subdivided into four groups: zero, one to three, four to seven, and eight or more. The accuracy of preoperative ultrasound and endoscopic ultrasound diagnosis exceeded 70% in each category of TNM classification. The incidence of lymph node metastasis determined by preoperative and histologic diagnosis was 69.0% (234/339) and 59.3% (201/339), respectively. The correlation between preoperative and histologic diagnosis was significant (P < .0001). According to the subdivision of number of lymph node metastases, the accuracy rates associated with nodal involvement of zero, one to three, four to seven, and eight or more were 83.8%, 59.7%, 43.3%, and 96.0%, respectively. The clinical outcome between ultrasound and endoscopic ultrasound diagnosis and histologic diagnosis in stage grouping was almost similar. The 5-year survival rates of patients with zero, one to three, four to seven, and eight or more lymph node metastases determined by ultrasound and endoscopic ultrasound were 53.3%, 33.8% 17.0%, and 0%, respectively. The differences among groups were statistically significant. The survival curves associated with preoperative and histologic diagnosis were similar. Not only the stage grouping of TNM classification but also the number of lymph node metastases determined by ultrasound and endoscopic ultrasound before surgery may be useful for predicting prognosis in patients with esophageal carcinoma.