Zarineh Alireza, Leon Marino E, Saad Reda S, Silverman Jan F
Department of Pathology and Laboratory Medicine, Allegheny General Hospital/Drexel University College of Medicine, 320 East North Avenue, Pittsburgh, PA 15212, USA.
Patholog Res Int. 2010;2010:614280. doi: 10.4061/2010/614280. Epub 2009 Sep 1.
Primary or idiopathic hypertrophy of the pyloric muscle (IHPM) is a rare entity with uncertain pathogenesis which both clinically and pathologically mimics gastric cancer. We present a rare late-occurring case of IHPM in a 71-year-old Caucasian man with no apparent predisposing factor. Imaging studies demonstrated gastric distension with air fluid levels and no evidence of extrinsic compression. At upper endoscopy, massive gastric distension and no evidence of any ulcer or other mucosal defects were observed. Microscopically, marked hypertrophy of muscularis mucosa with smooth muscle cells arranged in whorls and fascicles was present which gradually transitioned to normal areas. The muscle fibers stained with smooth muscle actin and trichrome stain highlighted fibrosis between the muscle fibers. Although uncommon, IHPM can clinically and histologically mimic other proliferations in the gastric wall, such as gastrointestinal stromal tumor or a spindle cell neoplasm. The recent advances in understanding the pathogenesis of IHPM are discussed.
原发性或特发性幽门肌肥大（IHPM）是一种发病机制不明的罕见病症，在临床和病理上都与胃癌相似。我们报告了一例罕见的迟发性IHPM病例，患者为一名71岁的白种男性，无明显诱发因素。影像学检查显示胃扩张伴气液平面，无外在压迫迹象。上消化道内镜检查发现胃大量扩张，未发现任何溃疡或其他黏膜缺损。显微镜下可见黏膜肌层明显肥大，平滑肌细胞呈漩涡状和束状排列，并逐渐过渡到正常区域。肌纤维经平滑肌肌动蛋白染色，三色染色突出显示了肌纤维之间的纤维化。尽管IHPM不常见，但在临床和组织学上可与胃壁的其他增殖性病变相似，如胃肠道间质瘤或梭形细胞瘤。本文讨论了近期在理解IHPM发病机制方面的进展。
