Noh Byeong-Joo, Park Sun Jin, Jang Jae-Young, Kim Youn Wha
Department of Pathology, Gangneung Asan Hospital, University of Ulsan College of Medicine, Gangneung, Korea.
Department of Surgery, Kyung Hee University Hospital, Kyung Hee University College of Medicine, Seoul, Korea.
J Minim Invasive Surg. 2022 Mar 15;25(1):32-35. doi: 10.7602/jmis.2022.25.1.32.
Dome-type carcinoma (DC) has been recognized as a rare variant of adenocarcinoma, which arises in gut-associated lymphoid tissue. It has a specific morphologic feature of a dome-like protrusion associated with lymphoid tissue. We report a case of a DC of the rectum in an asymptomatic 58-year-old male. A 2-cm sized, well-demarcated, round mass masquerading as a submucosal tumor (SMT) was identified in the rectum and was resected by endoscopic submucosal dissection. The tumor was revealed as an adenocarcinoma with submucosal invasion of 3,700 µm, which consisted of dilated cystic glands and the lymphoid stroma with reactive germinal centers. On immunohistochemistry, the tumor cells revealed retained expression for mismatch repair proteins. Laparoscopic surgical resection was subsequently performed. DC is considered a distinctive subtype of colorectal adenocarcinoma with characteristic morphology and low-grade malignant potential. Careful detection of the overlying mucosal lesion is crucial to differentially diagnose DC from SMT.
穹顶型癌（DC）已被公认为腺癌的一种罕见变体，起源于肠道相关淋巴组织。它具有与淋巴组织相关的穹顶状突起这一特定形态特征。我们报告一例58岁无症状男性直肠DC病例。在直肠中发现一个2厘米大小、边界清晰的圆形肿块，伪装成黏膜下肿瘤（SMT），并通过内镜黏膜下剥离术切除。肿瘤为腺癌，黏膜下浸润深度为3700微米，由扩张的囊性腺体和具有反应性生发中心的淋巴间质组成。免疫组化显示，肿瘤细胞错配修复蛋白表达保留。随后进行了腹腔镜手术切除。DC被认为是结直肠癌的一种独特亚型，具有特征性形态和低恶性潜能。仔细检测覆盖的黏膜病变对于将DC与SMT进行鉴别诊断至关重要。
