The patient was sent to a tertiary care center for further evaluation.  

Repeat endoscopic biopsy of the esophageal mass again showed primarily squamous epithelium, although a single fragment of tissue showed monotonous spindle cells. Based on the specimen, the differential diagnosis included esophageal gastrointestinal stromal tumor, leiomyoma, or less likely a schwannoma. There was not enough tissue to run immunohistochemistry analysis.

Due to progressive symptoms and indeterminate etiology of the mass, it was decided to resect the mass. An initial attempt was made at endoscopic excision; however, the mass was too large to be encircled by cautery snare, and so resection was achieved by transcervical approach.

Intraoperatively, it was discovered that the mass originated from the hypopharynx (above the level of the cricopharyngeus), and hung from a pedicle down into the lower esophagus.  The surgical pathology showed a 11 cm submucosal mass consistent with leiomyosarcoma.