Mixed adeno(neuro)endocrine carcinoma arising from the ectopic gastric mucosa of the upper thoracic esophagus

We report a case of mixed adenoendocrine carcinoma of the upper thoracic esophagus arising from ectopic gastric mucosa. A 64-year-old man who had been diagnosed with an esophageal tumor on the basis of esophagoscopy was referred to our hospital. Upper gastrointestinal endoscopy revealed the presence of ectopic gastric mucosa and an adjacent pedunculated lesion located on the posterior wall of the upper thoracic esophagus. Subtotal esophagectomy with three-field lymph node dissection was performed. A microscopic examination revealed that there was a partially intermingling component of neuroendocrine carcinoma adjacent to a tubular adenocarcinoma which was conterminous with the area of the ectopic gastric mucosa. Although the tubular adenocarcinoma was confined to the mucosa and submucosa, the neuroendocrine carcinoma had invaded the submucosaand there was vascular permeation. Each component accounted for 30% or more of the tumor, so the final histopathological diagnosis was mixed adenoendocrine carcinoma of the upper thoracic esophagus arising from ectopic gastric mucosa. Adjuvant chemotherapy was not performed, because the postoperative tumor stage was IA. The patient was well and had no evidence of recurrence 16 months after surgery.