Background Extremely well-differentiated adenocarcinoma (EWDA) is a deceptively bland-looking adenocarcinoma of the stomach. It often causes diagnostic problems, especially in endoscopic biopsy samples. To better recognize this deceptively bland lesion, we carefully reviewed a series of EWDAs treated at our institution.
Methods A total of 55 specimens from 19 patients were obtained. Endoscopic, gross and microscopic features defining EWDA were described and documented. For comparison, hyperplastic polyp specimens were randomly selected and analyzed.
Results Most cases (18 of 19, 94.7%) were advanced gastric cancer (AGC) and primarily located in the body of the stomach (15 of 19, 79.0%). The majority of AGCs were non-ulcerated (11 of 18, 61.1%) with an undermining growth pattern and a relatively small mucosal involvement. Specific histologic features included an irregular glandular shape, an undulating apical cytoplasmic border, disproportionately large glands, a variably distended mucinous cytoplasm. Classical features, such as small infiltrating glands or desmoplastic reactions, were barely observed. Identification of irregularly spaced nuclei and disruption of the foveolar epithelial structure, along with atypical features described above were helpful in making a diagnosis especially in gastric forceps biopsies.
Conclusions Awareness of the histomorphologic characteristics described in this report would lead to timely diagnosis and prevent repeated endoscopic procedures.
Citations
Citations to this article as recorded by
Unusual or Uncommon Histology of Gastric Cancer Jinho Shin, Young Soo Park Journal of Gastric Cancer.2024; 24(1): 69. CrossRef
A case of gastric adenocarcinoma with pyloric gland-type infiltrating submucosa Kaiho Hirata, Shusuke Yagi, Hideki Miyazaki, Kazuhiko Yamada, Naoki Akazawa, Naoki Enomoto, Kyoko Nohara, Chizu Yokoi, Toru Igari, Norihiro Kokudo Surgical Case Reports.2024;[Epub] CrossRef
Gastric-type extremely well-differentiated adenocarcinoma of the stomach: A rare tumor with diagnostic difficulties and high inter-observer variation in endoscopic pinch biopsies Soomin Ahn, Sujin Park, Hyun Hee Koh, Han Gyeol Kim, Hyunjin Kim, Jae Yeong Son, Boram Lee, Hyunwoo Lee, Soohyun Hwang, Junhun Cho, Yun Kyung Lee, Ryoji Kushima, Amitabh Srivastava, Kyoung-Mee Kim Pathology - Research and Practice.2024; 263: 155599. CrossRef