A Submucosal Tumor-like Lesion of the Cervical Esophagus Similar to the Tonsillar Structures of Waldeyer's Ring: A Case Report.

Esophageal submucosal tumors are rare, but their pathological types are diverse. In addition to the relatively common leiomyomas, some rare submucosal lesions are occasionally reported. Waldeyer's ring is described as a unique subtype of mucosa-associated lymphoid tissue, located in the naso-oropharynx. Studies have reported that Waldeyer's ring is the most common site of primary extranodal lymphoma in the head and neck. Interestingly, we encountered an esophageal submucosal tumor-like lesion similar to the tonsillar structures of Waldeyer's ring. A 38-year-old man underwent esophagoscopy after experiencing swallowing discomfort for 3 months. A protruding submucosal mass with slightly rough mucosa was found at the cervical esophagus approximately 20 cm from the incisors. Considering the possibility of the coexistence of a submucosal tumor and a mucosal lesion, as well as the continuous symptoms of swallowing discomfort, the patient underwent endoscopic submucosal dissection. The lesion was removed en bloc. However, histology revealed a lesion similar to the tonsillar structure of Waldeyer's ring between the lamina propria and submucosa. The patient was followed up for 6 months without recurrence or complaints. We report a new submucosal lesion and discuss its origin and treatment. Diagnostic ESD might be an effective option until its malignant potential is clarified.