Invasive inflammatory fibroid polyp of the stomach: a case report and literature review

Abstract

BackgroundInflammatory fibroid polyps (IFPs) are rare mesenchymal lesions that affect the gastrointestinal tract. IFPs are generally considered benign, noninvasive lesions; however, we report a case of an invasive gastric IFP. To the best of our knowledge, this is only the second case report of an invasive gastric IFP.Case presentationA 62-year-old woman presented with complaints of epigastric pain and vomiting. Computed tomography showed a 27-mm, hyper-enhancing tumor in the prepyloric antrum. Upper endoscopy also showed a submucosal tumor causing subtotal obstruction of the gastric outlet. Because a gastrointestinal stromal tumor was suspected, distal gastrectomy was performed. Histopathological examination revealed spindle cell proliferation in the submucosal layer. The spindle cells had invaded the muscularis propria layer and extended to the subserosal layer. The tumor was finally diagnosed as an IFP based on immunohistochemical findings. No mutations were identified in the platelet-derived growth factor receptor alpha (PDGFRA) gene via molecular genetic analysis.Discussion and conclusionsAfter the discovery that IFPs often harbor PDGFRA mutations, these growths have been considered neoplastic lesions rather than reactive lesions. Based on the present case, IFPs might be considered not only neoplastic but also potentially invasive lesions.

Inflammatory fibroid polyp: an unusual cause of abdominal pain in the upper gastrointestinal tract A case report

“…At the same time, it is often located in the submucosa and originated from the muscularis propria. It has a certain invasiveness and can be transferred, while there are still some IFP cases reported to be invasive though in a rareness [8]. The performance of a GIST under endoscopy is too similar to that of our case [9].…”

Inflammatory Fibroid Polyp of the Small Intestine: A Case Report and Systematic Literature Review

“…Immunohistochemically, IFPs are positive for smooth muscle actin, CD68 and CD34 and negative for S100 protein, CD117 and cytokeratin AE1/AE2. On the other hand, gastrointestinal stromal tumors (GISTs) are positive for CD117, schwannomas for S100 protein and inflammatory myofibroblastic tumors are negative for CD34 [8,66]. The distinction to GISTs is based on different morphology and clinical behavior, although both lesions frequently have PDGFRA mutations [7].…”

“…Therefore, further diagnostics and follow up are not recommended. However, recently three case reports have been published that showed the invasion of IFP through the muscularis propria layer, one in the ileum [79] and two in the stomach [66,80].…”

Inflammatory fibroid polyp in the antrum co-occurring with adenomatous polyp in the ascending colon

“…Histologically IFPs are submucosal (but often expand to the mucosa) with a well-developed network of capillaries, characteristic “onion skin” arrangement of spindle cells around vessels, and infiltration of eosinophils and lymphocytes [12]. Histopathologically they should be differentiated with gastrointestinal stromal tumors (GISTs), schwannomas, and inflammatory myofibroblastic tumours [13]. Immunohistochemical staining of IFPs is usually positive for CD-34 and negative for CD-117 and S-100 protein [12, 13].…”

“…Histopathologically they should be differentiated with gastrointestinal stromal tumors (GISTs), schwannomas, and inflammatory myofibroblastic tumours [13]. Immunohistochemical staining of IFPs is usually positive for CD-34 and negative for CD-117 and S-100 protein [12, 13]. This type of polyp is associated with mutation in the PDGFR-A gene, a feature shared with gastrointestinal stromal tumours [12, 13].…”