• 作者：Ana M. Vallejo-Bení ; tez^a ; Judith Suá ; rez-Aguado^b ; Montserrat Mora-Cabezas^a ; Teresa Aramendi^b ; Margarita Gimeno^b ; José ; Salas^c ; Ricardo Gonzá ; lez-Cá ; mpora^a ; ^{rcampora@us.es}
• 关键词：Mixoma ; Fibromixoma ; Estó ; mago ; Antro ; Tumores del estroma gastrointestinal
• 刊名：Revista Espa?ola de Patolog¨ªa
• 出版年：2013
• 出版时间：April-June, 2013
• 年：2013
• 卷：46
• 期：2
• 页码：93-100
• 全文大小：1005 K

Plexiform, angiomyxoid myofibrobastic tumour, or plexiform fibromyoma, is a rare, recently described, benign neoplasm that affects the gastric antrum. Histologically the tumour has a plexiform growth pattern and is composed of fibro/myofibroblastic cells in a variable mixed stroma with a prominent capillary network. We have reviewed the literature and present 2 further cases occurring in young patients (36 and 46 years of age) who presented with gastric discomfort and upper gastrointestinal bleeding. Both lesions were located in the submucosa and muscularis and showed a plexiform growth pattern. Fusiform cells were found in an abundant myxoid extracellular matrix. Numerous small fine-walled blood vessels were present. Immunohistochemistry revealed positivity for smooth muscle actin, vimentin, h-caldesmon and desmin (in one case) and negativity for CD117, DOG1, EMA, S100, ¦Â-catenin and CD34. Molecular studies showed no mutations in the KIT and PDGFRA genes in either case. To date, neither of the patients has recurrences or metastases, 4 years and 8 months after diagnosis.

Differential diagnosis includes a wide variety of myxoid lesions that may arise in or invade the stomach wall (GIST, intraabdominal desmoid tumour, inflammatory fibroid polyp, leiomyoma-leiomyosarcoma, perineuroma, schwannoma and neurofibroma), among these, plexiform neurofibroma is the only one showing the characteristic growth pattern.

In our review of the literature, we found 23 cases described as gastric plexiform angiomyxoid myofibroblastic tumour, or gastric plexiform fibromyxoma. However, before the introduction of these terms, similar, if not completely characterized, gastric myxoid lesions had been described in the gastric antrum, suggesting that a single entity with a variable degree of fibro/myofibroblastic differentiation and a plexiform growth pattern might exist, perhaps developing in cells found only in the stomach.