2023 Volume 49 Issue 3 Pages 267-272
We report a case of a hypopharyngeal tumor that was suspected to be malignant on preoperative endoscopic findings, but was diagnosed as glycogenic acanthosis on pathological examination. The patient was a 72-year-old man. During follow-up after radiotherapy for right glottic cancer, a small lesion of the right piriform sinus was found. The lesion enlarged and increased in thickness, and atypical vessels on its surface became evident, so transoral resection was performed. Intraoperative magnifying endoscopy showed abnormal vessels like type B1 vessels on its surface, suggesting early-stage cancer, but intraoperative Lugol staining showed the lesion to be dark brown with a pink color sign-negative non-staining zone adjacent to it. Pathological examination of the excised specimen confirmed the diagnosis of glycogenic acanthosis with dysplasia of the adjacent zone. In superficial lesions of the hypopharynx, glycogenic acanthosis, which is difficult to distinguish from cancer, should be included in the differential diagnosis, and the diagnosis and treatment should be made after comprehensive evaluation of the lesion using magnifying endoscopy and Lugol staining.
