Yamada Rin, Horiguchi Shin-Ichiro, Onishi Tomoko, Motoi Toru, Hishima Tsunekazu
Department of Pathology, Tokyo Metropolitan Cancer and Infectious Diseases Center, Komagome Hospital, 3-18-22, Honkomagome, Bunkyo-ku, Tokyo 113-8677, Japan.
Department of Gastroenterology, Tokyo Metropolitan Cancer and Infectious Diseases Center, Komagome Hospital, 3-18-22, Honkomagome, Bunkyo-ku, Tokyo 113-8677, Japan.
Case Rep Pathol. 2018 Aug 28;2018:3620293. doi: 10.1155/2018/3620293. eCollection 2018.
Gastric carcinoma with enteroblastic differentiation (GCED) is a rare variant of gastric carcinoma, and a part of GCED produces alpha-fetoprotein. GCED is characterized by cells with clear cytoplasm and a tubulopapillary and solid growth pattern resembling those in the primitive gut. GCED is typically overlaid by a conventional adenocarcinoma (CA) component, implying that CA in the mucosa differentiates into GCED during tumor invasion and proliferation. We present the case of a 73-year-old woman with a 10-mm superficial elevated lesion and a slight central depression at the anterior wall of the lower gastric body. Endoscopic submucosal dissection revealed tumor cells having clear cytoplasm and severely atypical nuclei characteristic of GCED. The growth pattern was predominantly solid and trabecular but included submucosal layer invasion and limited tubular growth. Atrophic pyloric mucosa without intestinal metaplasia surrounded the tumor. Immunohistochemically, the tumor cells were positive for AFP, GPC3, and SALL4. The present patient showed a purely enteroblastic differentiation without a CA component despite the presence of early cancer, indicating that few cases of GCED may arise de novo in the gastric mucosa. GCED is more aggressive compared with CA; therefore, pathologists should be aware that GCED without CA can appear in biopsy specimens of early cancer while making an accurate diagnosis.
具有成肝细胞样分化的胃癌（GCED）是胃癌的一种罕见变体，部分GCED会产生甲胎蛋白。GCED的特征是细胞胞质清晰，呈管状乳头状和实体生长模式，类似于原始肠道中的细胞。GCED通常覆盖有传统腺癌（CA）成分，这意味着黏膜中的CA在肿瘤侵袭和增殖过程中分化为GCED。我们报告一例73岁女性病例，其胃体下部前壁有一个10毫米的浅表隆起性病变，中央有轻微凹陷。内镜下黏膜下剥离术显示肿瘤细胞具有清晰的胞质和GCED特征性的严重非典型核。生长模式主要为实体状和小梁状，但包括黏膜下层浸润和有限的管状生长。肿瘤周围是无肠化生的萎缩性幽门黏膜。免疫组化显示，肿瘤细胞AFP、GPC3和SALL4呈阳性。尽管存在早期癌症，但本病例显示为纯粹的成肝细胞样分化，无CA成分，这表明很少有GCED病例可能在胃黏膜中从头发生。与CA相比，GCED更具侵袭性；因此，病理学家在进行准确诊断时应意识到，无CA的GCED可能出现在早期癌症的活检标本中。
