Endoscopic submucosal dissection of a tumor in the upper esophageal sphincter and piriform sinus. We present a 77-year-old male who initially underwent routine EGD for gastroesophageal reflux that demonstrated mucosal irregularity at the proximal esophagus and upper esophageal sphincter. The patient was brought back for an endoscopic ultrasound for evaluation of the mucosal irregularity with EUS revealing a raised UT1AN0MX mass at the cricopharyngeus and the upper esophageal sphincter concerning for a likely malignant esophageal tumor. Biopsy was then done confirming squamous cell carcinoma and after discussion with the cardiothoracic and ENT surgery, it was decided that surgery would be both extensive and complicated involving an esophagectomy and laryngectomy. EGD was then pursued in an attempt to preserve the patient's quality of life while pursuing complete removal of the squamous cell carcinoma. On EGD, we initially visualized the 2-centimeter flat mucosal mass with no bleeding and no stigmata of recent bleeding in the upper esophageal sphincter. This was measured at 18 to 20 centimeters from the incisors. The mass was partially circumferential. In other words, it involved one half of the lumen circumference and was observed using both Lugol's solution and chromoendoscopy. Preparations were made for endoscopic submucosal dissection. We began the case by thermally marking the borders of the lesion as to quickly identify the location of the mass and resection area. Careful measures were taken to ensure accurate marking throughout this procedure. This was then followed by injection of 37 milliliters of O-Rise, providing adequate lift of the lesion from the muscularis propria, allowing for a smooth dissection to be carried out. We then began by creating a circumferential incision around the lesion into the submucosa, performing a mucosotomy using a dual knife, careful to avoid damage to any surrounding structures while ensuring the mass was resected in its entirety. Once this was complete, the lesion was then dissected from the underlying deep submucosal layers utilizing a triangle-tipped knife and retrieved with a cap. A total 25 millimeter area was resected. Visualization of the resected area was then pursued to help ensure total resection of the mass with no bleeding witnessed upon completion of the procedure. This case helps demonstrate that resection of lesions in the cricopharyngeus and the upper esophageal sphincter can be done ensuring complete resection of the esophageal mass. While these cases may be technically difficult given the location of these tumors, this procedure may help avoid complex surgeries that would otherwise involve removal of the larynx and the esophagus. Successful endoscopic submucosal resection of the two centimeter flat mucosal mass at the piriform sinus and the upper esophageal sphincter was complete with pathology showing a PT1B SM1 poorly differentiated squamous cell carcinoma with negative deep and lateral margins R0 resection along with no lymphovascular invasion noted. Adjuvant chemotherapy was recommended due to the tumor invading into the submucosal layer along with the cancer being poorly differentiated. The patient has since completed six cycles of concurrent chemoradiation and is recovering well. Once again, our case helps demonstrate that resection of lesions in the cricopharyngeus and the upper esophageal sphincter may help avoid complex surgeries that would otherwise involve removal of the larynx and the esophagus.

endoscopic submucosal dissection

upper esophageal sphincter

piriform sinus

squamous cell carcinoma

endoscopic resection