Gastrointestinal: Extramammary Paget disease of the esophagus.

A 74-year-old man with a history of drinking and smoking underwent esophagogastroduodenoscopy during a medical check-up. Circumferential ring-shaped scars were observed from the middle to lower esophagus (Fig. 1a), and narrow-band imaging (NBI) also showed white ring-shaped scars, and the background color did not change (Fig. 1b). Lugol’s iodine staining showed an unstained area spread throughout (Fig. 1c). There were no findings of reflux esophagitis at the esophagogastric junction. A 10-mm-sized reddish flat elevated lesion was found at the lower esophagus (Fig. 1d). Biopsy specimens of the elevated lesion revealed squamous cell carcinoma (SCC). Esophagectomy with lymph node dissection was performed. Histopathological examination of the circumferential ring-shaped scars region in the resected specimen revealed a large number of atypical cells with clear nuclei and weakly acidic vesicles along the basal layer of squamous epithelium that appeared to be Paget cells (Fig. 2a). Immunohistochemical staining was partially positive for periodic acid-Schiff with diastase staining (PAS-D) and Alcian blue; positive for p53, CK7, and GCDFP15; and negative for CK5/6 and CK20 (Fig. 2b–g). HMB-45 and Melan Awere negative. Based on these examinations, the diagnosis was extramammary Paget disease of the esophagus. The pathological examination of the lower esophageal tumor was moderately to poorly differentiated SCC, depth of submucosa, negative lymphovascular invasion, and negative lymph node metastasis (Fig. 2h, i). Extramammary Paget disease of the esophagus is very rare. The definition of Paget disease is intraepithelial growth of neoplastic cells showing glandular differentiation. Primary extramammary Paget disease is thought to be derived from an underlying neoplastic transformation of the intraepidermal portion of a sweat gland such as in vulvar and perianal Paget disease, whereas almost esophageal Paget disease is caused by the intraepidermal spread of neoplastic cells, typically derived from an underlying invasive SCC and poorly differentiated adenocarcinoma of the esophagogastric junction. In this case, it is presumed that the Paget cells were derived from poorly differentiated SCC and developed with glandular differentiation. The endoscopic findings of esophageal Paget disease have been rarely described in previous reports. Circumferential ring-shaped scars and widespread Lugol’s iodine non-staining may be characteristic endoscopic findings of esophageal Paget disease. When circumferential ring-shaped scars of the esophagus coexisting with esophageal cancer are observed, the possibility of Paget disease should be considered.