Fig. 1

Upper gastrointestinal endoscopy in our case: a White light endoscopy shows a 1.5*0.6 cm lesion covered by smooth, normal mucosa; b EUS indicates well-defined, slightly heterogeneous, and hypoechoic lesions that might have originated from the submucosal layer; c two hypoechoic masses of approximately 1.5*1.5 cm and 1.1*1.0 cm in the mediastinum, with uniform echoes and clear boundaries, which were considered to be enlarged lymph nodes; d lesion specimen removed by ESD