Endoscopic Resection of Hypopharyngeal Squamous Cell Carcinoma
A 55-year-old Asian male was referred to our department for the management of suspicious hypopharyngeal cancer diagnosed by endoscopic biopsy at a primary medical clinic. The patient was not present with symptoms related to hypopharyngeal disease, such as dysphagia or throat discomfort. He was a 40-pack/year current smoker and consumed alcohol on a regular basis (>3 times per week). He had previously undergone Ivor-Lewis operation for esophageal squamous cell carcinoma (pT1N0M0) 1 year ago. Pathologic review of the biopsy specimen from the referring clinic showed squamous cell carcinoma. Endoscopic examination disclosed a round slightly elevated hyperemic mucosal lesion, approximately 8 mm at the longest diameter, at the right pyriform recess (). NBI showed dilated, tortuous and irregular intrapapillary ca-pillary loops (IPCL), consistent with type V IPCL pattern described by Inoue et al. (). Contrast enhanced neck and chest computed tomography (CT) scans showed no evidence of focal lesions or lymph node enlargement in the head and neck region, and positron emission tomography-CT scans were unrevealing. Based on these findings we diagnosed stage I early hypopharyngeal squamous cell carcinoma (cT1N0M0). The patient refused extensive resection and endoscopic resection was planned. Endoscopic resection was performed under general anesthesia. A cap fitted, forward-viewing, sterilized endoscope (EG2001i; Pentax Medical Systems Corp., Tokyo, Japan) was used for the entire procedure. Lugol's solution was applied for demarcation of the lesion, and marking around the lesion was performed with the Dual knife (KD-650Q; Olympus, Tokyo, Japan). Saline solution with 0.001% epinephrine and 0.004% indigo carmine dye was injected with a 23-gauge needle (NM-200L-0423; Olympus) into the submucosa under and around the lesion for mucosal elevation. After sufficient mucosal elevation around the lesion had been achieved, a snare was introduced into the accessory channel and suction was applied. The lesion was ensnared and resected en bloc using the cap assisted endoscopic mucosal resection (EMR-C) technique. The total procedure time was 35 minutes, and no complications occurred during the procedure. The resected specimen measured 10×9 mm and an erythematous elevated lesion was observed in the center of the specimen ().\nImmunohistochemical staining and pathologic analysis was consistent with squamous cell carcinoma in situ with p53 protein overexpression in the full thickness of the epithelial layer (). Both lateral and vertical resection margins were free from involvement of the tumor. The patient recovered without incident and was discharged on the 6th postoperative day. Six months later on routine endoscopic follow-up, a slightly depressed hyperemic lesion was observed at the opposite left pyriform sinus (). Although endoscopic biopsy was negative, NBI showed an irregular vascular pattern () and additional EMR-C was performed (). Final pathologic results showed low grade dysplasia with focal p53 protein overexpression confined to the lower one-third of the epithelial layer ().