title: Differentiated adenocarcinoma with a gastric phenotype in the stomach: difficulties in clinical and pathological diagnoses.
abstract: Differentiated-type adenocarcinoma with gastric phenotype of the stomach is rare and is difficult to diagnose both clinically and pathologically. We report a case of differentiated-type adenocarcinoma with a gastric phenotype in the stomach. A 60-year-old Japanese female was referred to our hospital with gastric cancer. A barium meal examination and esophagogastroduodenoscopy revealed a granular elevated lesion in the lower body near the lesser curvature and a depressed lesion on the antrum. A biopsy specimen showed benign atrophic mucosa in a granulated lesion and moderately differentiated adenocarcinoma in the depressed lesion. The patient underwent laparoscopy-assisted distal gastrectomy with lymph node dissection. The postoperative course was uneventful. Histological examination of the resected tissue confirmed well-differentiated adenocarcinoma in the granulated lesion and moderately differentiated adenocarcinoma in the depressed lesion, without lymph node metastasis. Both lesions were confined to the mucosa. Since mucin immunohistochemistry revealed MUC5AC-positive staining in the granulated lesion, the final diagnosis was differentiated-type adenocarcinoma with gastric phenotype in the stomach. Despite the high malignant potential, the clinical and pathological diagnoses of gastric-type differentiated adenocarcinoma are often difficult. Mucin immunohistochemistry together with hematoxylin and eosin (HE) staining may be helpful in the pathological diagnosis of this rare disease.
authors.affiliation: Department of Surgery, Kochi Medical School, Kohasu-Okocho, Nankoku, Kochi, 783-8505, Japan. tsutomun@kochi-u.ac.jp.
authors.forename: Tsutomu
authors.initials: T
authors.lastname: Namikawa
authors.affiliation: Department of Human Health and Medical Sciences, Kochi Medical School, Nankoku, Kochi, Japan.
authors.forename: Michiya
authors.initials: M
authors.lastname: Kobayashi
authors.affiliation: Department of Surgery, Kochi Medical School, Kohasu-Okocho, Nankoku, Kochi, 783-8505, Japan.
authors.forename: Hiroyuki
authors.initials: H
authors.lastname: Kitagawa
authors.affiliation: Department of Surgery, Kochi Medical School, Kohasu-Okocho, Nankoku, Kochi, 783-8505, Japan.
authors.forename: Takehiro
authors.initials: T
authors.lastname: Okabayashi
authors.affiliation: Department of Surgery, Kochi Medical School, Kohasu-Okocho, Nankoku, Kochi, 783-8505, Japan.
authors.forename: Takeki
authors.initials: T
authors.lastname: Sugimoto
authors.affiliation: Department of Gastroenterology and Hepatology, Kochi Medical School, Nankoku, Kochi, Japan.
authors.forename: Yoshinori
authors.initials: Y
authors.lastname: Kuratani
authors.affiliation: Laboratory of Diagnostic Pathology, Kochi Medical School Hospital, Nankoku, Kochi, Japan.
authors.forename: Manabu
authors.initials: M
authors.lastname: Matsumoto
authors.affiliation: Department of Surgery, Kochi Medical School, Kohasu-Okocho, Nankoku, Kochi, 783-8505, Japan.
authors.forename: Kazuhiro
authors.initials: K
authors.lastname: Hanazaki
keywords: Differentiated adenocarcinoma; Early gastric cancer; Gastrectomy; Gastric phenotype; Mucin core protein; Mucous phenotype