Serial endoscopic ultrasound in the assessment of response to chemoradiotherapy for carcinoma of the esophagus

The aim of the study was to assess whether endoscopic ultrasound (EUS) could accurately measure the locoregional response to chemoradiotherapy in patients with carcinoma of the esophagus. Seventeen patients with esophageal carcinoma underwent EUS examination before and on completion of chemoradiotherapy. The EUS findings were correlated with the results of histologic examination of the esophagectomy specimen. The accuracy of EUS in these patients was compared with the accuracy of EUS in a control group of 17 patients treated by surgery alone. In 16 of 17patients EUS-determined tumor (T) stage was unchanged following treatment and in one patient there was T-stage progression. No patient demonstrated downstaging of the primary tumor according to classical EUS criteria. In 10 of 17 patients a reduction in maximum tumor depth of ≥2 mm was observed (range 2 to 18 mm). Histologic examination revealed that four patients with squamous cell carcinoma had experienced a complete pathologic response. These four patients had significantly lower posttreatment EUS tumor depths compared to patients without a complete response (5.0 vs. 9.0 mm; P