| Abstract: | Objective: The aim of the present study was to assess the usefulness of endoscopic ultrasonography (EUS) for evaluating the efficacy of neoadjuvant therapy for advanced esophageal carcinoma based on the Response Evaluation Criteria in Solid Tumors (RECIST). Patients and Methods: Sixty‐two patients with advanced esophageal carcinoma underwent surgical resection after neoadjuvant therapy. The maximal tumor thickness was measured by EUS before and after neoadjuvant therapy, and the percent reduction was compared with the pathological response. Based on the RECIST, PD‐SD (progressive disease‐stable disease) was defined as < 30% reduction of tumor thickness on EUS, PR (partial response) as ≥ 30% reduction of tumor thickness, and CR (complete response) as no detectable tumor (100%). Results: The percent reduction of the thickness of Grade 0–1, Grade 2 and Grade 3 tumor was 11.5 ± 21.0%, 48.2 ± 17.0% and 74.9 ± 21.1%, respectively. There were significant differences in the extent of reduction among the three groups. Based on the RECIST, 80% of Grade 0–1 cases, 91% of Grade 2 cases and 22% of Grade 3 cases were PD‐SD, PR, and CR according to EUS, respectively. EUS correctly identified 80% of non‐responders and 94% of responders. Conclusions: The percentage reduction of tumor thickness on EUS closely reflected the pathological evaluation. EUS evaluation based on the RECIST seems to be useful for monitoring neoadjuvant therapy in patients with esophageal carcinoma. |
