Neurogenic nature of so-called inflammatory fibroid polyps of the stomach

Giant Inflammatory Fibroid Polyp of the Descending Colon Treated with Endoscopic Resection

Inflammatory fibroid polyps (IFPs) of the colon are very rare, reactive, non-neoplastic polyps that may grow to large sizes but do not carry any risk of malignancy. Because of their size, IFPs are usually treated with surgery; however, size alone should not be an indication for surgery. Depending on the location and morphology of the polyp, endoscopic resection should be considered. We here describe a case of a giant IFP that was successfully removed with endoscopy without complication or recurrence.

Inflammatory fibroid polyp: a rare benign tumor of the alimentary tract in children presenting as intussusception-case report and review of literature

Inflammatory fibroid polyp (IFP) represents a rare cause of gastrointestinal polypoid disease in childhood. Τhe lesion has been described by various names beyond the currently accepted term, including “Vanek's tumour,” eosinophilic or submucosal granuloma, gastric fibroma with eosinophilic infiltration, inflammatory pseudotumor, and hemangiopericytoma. The etiopathogenesis and origin of the mesenchymal spindle-shaped cells that comprise the polyp remains enigmatic. Recent studies have shown familial occurrence, expression of platelet-derived growth factor receptor (PDGFRA) and oncogenic PDGFRA mutations in the majority of lesions, suggestive of a neoplastic nature. We present a rare case of a 10-year-old boy with an IFP of the terminal ileum, who presented acutely with intussusception and was treated with a right hemicolectomy. Postoperative course was uneventful and the patient has been asymptomatic during follow-up. Histopathology and immunohistochemical analysis excluded inflammatory myofibroblastic tumor (negative for Alk1, desmin, smooth muscle actin [SMA]), gastrointerstinal stromal tumors (GIST) (negative for CD117) and schwannoma (negative for S100). The lesion was positive for CD34 and faintly for vimentin. Despite the classification of IFPs as a mesenchymal benign neoplasm, in the vast majority of cases, surgical excision alone was curative, and no reports exist of a malignant transformation. A cautious approach with periodic surveillance of the affected children seems reasonable though.

An inflammatory fibroid polyp in the hepatic flexure of the colon treated with argon plasma coagulation, endoscopic clipping and polypectomy

Inflammatory fibroid polyp (IFP) is a rare benign polypoid lesion of the gastrointestinal tract. Most IFPs occur in the stomach and colonic occurrence is very rare. Histologically IFP is characterized by a mixture of numerous small vessels, fibroblasts and edematous connective tissue associated with marked inflammatory infiltration by eosinophils. We present a rare case of a pedunculated IFP in the hepatic flexure of the colon treated successfully with a combination of argon plasma coagulation, endoclipping and polypectomy. A 74-year-old asymptomatic female underwent a screening colonoscopy in our hospital. A 12-mm pedunculated polyp was found at the hepatic flexure of the colon. After saline injection, we attempted to remove the polyp with a hot snare. However the polyp stalk was extremely difficult to resect despite several attempts with the hot snare. We placed an endoclip at the base of the stalk and then applied argon plasma coagulation at 1.0 l/min and 40 W. After these measures we were able to resect the stalk and the polyp was retrieved. Histologically the polyp was located in the submucosa of the gastrointestinal tract. Proliferation of spindle cells and infiltration of inflammatory cells such as plasma cells and eosinophils were observed. The spindle cells were positive for CD34 and S100 but negative for c-kit and muscle markers. These findings are consistent with a histopathological diagnosis of IFP.

Inflammatory fibroid polyp occurring in the transverse colon diagnosed by endoscopic biopsy

A case of an inflammatory fibroid polyp occurring in the transverse colon and diagnosed by endoscopic biopsy is reported. The patient was an 82-year-old man who visited our hospital for further evaluation of occult blood in stool. The Colonoscopy revealed a small, red, and peduncular polyp, about 6 mm in diameter, in the transverse colon. Histological examination of the biopsy specimen obtained from the polyp revealed proliferation of fibroblasts and infiltration of inflammatory cells such as plasma cells and eosinophils. This polyp was diagnosed as an inflammatory fibroid polyp, which can appear in many different locations throughout gastrointestinal tract, though still rare in the transverse colon.

Vanek's tumor (inflammatory fibroid polyp). Report of 18 cases and comparison with three cases of original Vanek's series

Eighteen cases of Vanek's tumors are presented. The patients included nine men and nine women between the ages of 45 and 93 years (mean, 66.2 years). Nine cases were clinically diagnosed as polyps of the gastric antrum, five cases as polyps of the stomach (not otherwise specified), one polyp was located in the ileum and the three remaining polyps in the small intestine (not otherwise specified). The thirteen polyps with available size information measured from 0.4 to 5 cm in the greatest diameter (mean, 2.2 cm). Immunohistochemically, the affections were positive for vimentin (18/18) and CD34 (15/18). All the cases negative for CD34 also lacked concentric onion skin-like formations of the spindle cells around glands and vessels. The different immunophenotype and absence of concentric formations could be explained by the existence of two different lesions commonly designated as Vanek's tumor (inflammatory fibroid polyp) or by the hypothesis of various evolutional stages. In the differential diagnosis, it is important to distinguish namely eosinophilic gastroenteritis, gastrointestinal stromal tumor, inflammatory pseudotumor, hemangioendothelioma, and hemangiopericytoma. In contrast to gastrointestinal stromal tumors, genetically no substitution, deletion, or insertion occurred in c-kit exon 11 in all analyzed samples. Likewise, no deletion or insertion in part of c-kit exon 9 was observed.

Inflammatory Fibroid Polyps of the Gastrointestinal Tract

Inflammatory fibroid polyp (IFP) of the gastrointestinal tract is an uncommon proliferative lesion. When sampled by biopsy, IFP can be mistaken for various lesions, from granulation tissue to high-grade sarcoma. We present an unusual case of IFP and review a large series of IFPs to characterize clinical, histologic, and molecular features of diagnostic value. A total of 42 IFPs were gathered from the pathology archives of the University of Pittsburgh Medical Center over the past 22 years. Clinical, histopathologic, and immunohistochemical features were collected. A random subset of IFPs (n = 12) underwent microdissection genotyping for a broad panel of tumor suppressor gene-associated mutations (loss of heterozygosity). IFPs occurred in both sexes (male, 17; female, 25) over a broad age range (29-85 years). IFPs varied in size from 0.2 to 8 cm. The stomach (n = 19) was the most common location, followed by large bowel (n = 13) and small bowel (n = 10). Most IFPs displayed typical morphologic features (eosinophils admixed with loose, mature fibrous tissue), and in 2 instances, sampled by biopsy, IFP was confused for sarcoma. All IFPs lacked c-kit staining. No mutations were identified in any IFPs examined. IFP is a clinically underrecognized entity with unique morphologic and immunohistochemical features. On biopsy alone, the differential diagnosis may include sarcoma and other malignancies. The absence of mutational change may help to exclude malignant lesions.

Inflammatory fibroid polyps of the gastrointestinal tract: evidence for a dendritic cell origin

Inflammatory fibroid polyps (IFPs) are rare mesenchymal tumors of the gastrointestinal tract that consist of spindle-shaped stromal cells and an inflammatory infiltrate rich in eosinophils. Their etiology and histogenesis remain unknown. Based on previous reports of their immunoreactivity for CD34 and c-kit biomarkers, IFPs have been thought to be related to gastrointestinal stromal tumors (GISTs). After reviewing the current literature and examining IFPs at the light microscopic level, we evaluated a series of IFPs using an extensive panel of immunohistochemical and in situ hybridization markers in an effort to gain insight into their etiology and histogenesis and to determine their true relationship to GISTs. Sixteen routinely processed IFP specimens (14 gastric, 1 ileal, and 1 rectal) were immunohistochemically stained for antibodies to CD34, HMB-45, desmin, smooth muscle actin, calponin, h-caldesmon, anaplastic lymphoma kinase, S-100 protein, epithelial membrane antigen, c-kit (CD117), stem cell factor (SCF/N19 or kit ligand), p53, bcl-2, cyclin D1, and human herpesvirus-8 (HHV8). In situ hybridization for Epstein-Barr virus-encoded RNA (EBER) was also performed. Ten cases were further evaluated for the dendritic cell markers fascin, CD21, CD23, and CD35. Stromal cells were diffusely positive for CD34 and fascin in all (100%) cases, and these stromal cells were, in addition, immunoreactive for calponin and smooth muscle actin in 88% and 25% of cases, respectively. CD35 was also found to be focally reactive in the stromal cells. Cyclin-D1 was overexpressed in all (100%) IFPs. All other immunohistochemical markers and EBER were negative in the stromal cells. These findings suggest that the proliferating stromal cells in IFPs are of dendritic cell origin, with some cases also exhibiting myofibroblastic features. Absence of c-kit, SCF, and h-caldesmon immunoreactivity fails to support a relationship to GISTs. We also conclude that Epstein Barr virus and HHV8 are unlikely etiologic agents of IFPs. Overexpression of cyclin D1 in all cases suggests that a defect in cell-cycle regulation may be involved in the growth of IFPs.

Rare case of inflammatory fibrous polyp of the esophagus

Esophageal inflammatory fibrous polyps are extremely rare benign neoplasms. The manuscript illustrates a case of a man complaining of pyrosis and gastroesophageal reflux symptoms. Diagnostic work-up showed an expansive lesion of the distal esophagus simulating malignancy but with negative, repeated, multiple biopsies. The considerable size of the lesion, and the suspicion of a malignant tumor because of the presence of ulceration, indicated esophagectomy with extensive lymphadenectomy and intrathoracic esophagogastroplasty. The diagnosis of inflammatory polyp of the esophagus was achieved postoperatively. The Discussion deals with a review of the literature and considers the performed operation a good choice considering the hypothesis of a malign neoplastic evolution of this lesion.

Fibroid polyps of intestinal tract are inflammatory-reactive proliferations of CD34-positive perivascular cells

AIMS

Our aim was to determine the histogenesis of fibroid polyps (FP). These polyps are rare inflammatory-reactive, tumour-like lesions of unknown aetiology, arising in the submucosa or mucosa of the gastrointestinal tract. They are mainly due to a proliferation of characteristic spindle cells.

METHODS AND RESULTS

Nine FP were investigated by light microscopy and immunohistochemistry with endothelial markers (Factor VIII, CD34, CD31), a neuronal marker (S100), muscular markers (desmin, alpha-smooth muscle actin) and histiocytic markers (PGMI, KP1, MAC387) using the highly sensitive avidin-biotin-peroxidase technique. We demonstrate, for the first time, a consistent positivity of the characteristic spindle cells of FP for CD34. The proposed endothelial, histiocytic or neuronal origin of FP could be completely ruled out.

CONCLUSIONS

Because of the consistent positivity of the spindle cells of FP for CD34 we suggest an origin of these lesions from primitive perivascular or vascular cells. This origin and a probable relationship to gastrointestinal stromal tumours (GIST) is discussed.

Endoscopic evaluation of gastric inflammatory fibroid polyp

Clinical and endoscopic manifestations of 18 gastric inflammatory fibroid polyps (IFP) in 16 patients who underwent endoscopic or surgical removal were retrospectively analyzed. All of the lesions were located within the pyloric antrum, and the sizes varied from 0.8 to 7.0 cm. On endoscopy, six polyps which measured 1.0 cm or less uniformly seemed to be sessile or intramural tumors, whereas four of the nine polyps between 1.1 and 2.0 cm in size were additionally accompanied by a central depression. The remaining three, which measured more than 2.0 cm, showed characteristic polypoid growth with ulcerations. Three polyps more than 1.0 cm in size occasionally prolapsed into the duodenal bulb. Three patients with these prolapsing polyps and two with polyps accompanied by ulcerations experienced abdominal pain, nausea, or severe anemia. Two polyps (11%) were precisely diagnosed as IFP by means of conventional forceps biopsy. Histological examinations revealed that all of the polyps proliferated within the submucosa. Therefore, this type of polyp may be subject to endoscopic removal to enable a precise diagnosis and treatment.

The histogenesis of inflammatory fibroid polyps of the gastrointestinal tract

Inflammatory fibroid polyps are lesions occurring in the submucosa of the gastrointestinal tract. These lesions have been identified by a variety of names, indicative of their uncertain histogenesis. Three cases were studied by light microscopy and cytochemistry and, in one case, by electronmicroscopy. The most characteristic feature consisted of concentric fibrovascular structures. Peroxidase reaction for muscle actin and Ulex europeus agglutinin was positive in the two main cellular components. Electronmicroscopy revealed that the two principal cell constituents were endothelial and myocytic cells. These observations support the conclusion that inflammatory fibroid polyps are lesions of vascular origin.

Inflammatory fibroid polyp of the small intestine: ultrastructural and immunohistochemical observations

The ultrastructural and immunohistochemical features of a primary tumor of the ileum showing the classic histologic features of an inflammatory fibroid polyp (IFP) of the gastrointestinal tract are presented. Ultrastructurally the proliferating cells showed a combination of fibroblastic and histiocytic features, with abundant rough endoplasmic reticulum and active production of collagen in many of the cells and long, dendritic cytoplasmic projections with large cytoplasmic vacuoles containing remnants of phagocytosed cellular debris in others. Immunohistochemical studies showed strong cytoplasmic positivity in the proliferating cells with vimentin antibodies and scattered positivity with muramidase. Additional findings include the ultrastructural demonstration of oligocilia and occasional primitive intercellular junctions. The findings in this case suggest that IFP may represent a proliferation of primitive submucosal stromal cells exhibiting incomplete fibrohistiocytic differentiation.

Inflammatory fibroid polyp of the stomach in a child

A large inflammatory fibroid polyp of the stomach with endo-exophylic growth is described in a 5-year-old. CT and UGI demonstrate the lesion.

Inflammatory fibroid polyp of the stomach

Fourteen cases of inflammatory fibroid polyp of the stomach were studied in terms of immunohistochemistry and ultrastructure. They occurred as polypoid lesions in the antrum, except for two found in the body of the stomach. Out of the 14 cases, two were found to be multiple and the remainder solitary. In all but one lesion, the mucosal layer was involved and six lesions were entirely localized within the mucosal layer, suggesting that inflammatory fibroid polyps of the stomach originate in the mucosal layer. Neither S100 protein, factor VIII-related antigen, alpha 1-antitrypsin nor lysozymes were found in the cytoplasm of the proliferating cells. The ultrastructures of the proliferating cells were fibroblastic rather than neurogenic, angiogenic, or myofibroblastic. These findings suggest that the cells are fibroblasts, though the possibility that they are facultative fibroblasts remains. An interesting observation made with electron microscope was the infection of micro-organisms similar to mycoplasma. This seems to deserve further investigation as a possible etiologic factor of the disease.

Inflammatory fibroid polyps of the gastrointestinal tract. An immunohistochemical and electron microscopic study

Seven cases of inflammatory fibroid polyp (IFP) are studied, two of them with electron microscopy. The morphologic findings suggest a myofibroblastic origin for the proliferating cells. Other histogenetic hypothesis which propose a neural or vascular nature for this lesion are ruled out. The ultrastructural features of the proliferating cells are different from schwann and endothelial cell tumors. Moreover, the immunohistochemical technique to detect Factor VIII related antigen was negative in the intercapillary cells of the seven cases. Our conclusion is that inflammatory fibroid polyp of the gastrointestinal tract represent a reactive lesion of myofibroblastic nature.

Intussusception due to inflammatory fibroid polyps of the ileum: a report of 12 cases from Africa

Eleven cases of inflammatory fibroid polyp of the ileum from Malawi and 1 from Sierra Leone are described. All 12 patients presented with acute intestinal obstruction as a result of an intussusception caused by the polyp. The lesions are characterized by a variable proliferation of fibroblasts and small vessels which may involve the whole thickness of the bowel wall. Tissue mast cells and eosinophils were noted in the polyps. The aetiology of these lesions remains obscure but they appear to be reactive rather than neoplastic. The condition appears to occur more commonly in Malawi than in the United Kingdom or North America and is an important cause of small bowel obstruction in that part of Africa.

Inflammatory fibroid polyp of the gastrointestinal tract

Details of 13 new cases of inflammatory fibroid polyp of the gastrointestinal tract and of 76 patients recorded in the literature (total 89) are described and analysed. The lesion is always benign, may occur at any age but is commonest in the sixth and seventh decades, and involves the stomach most frequently. Abdominal pain, often related to obstruction, is the principal symptom. Eosinophilia of the peripheral blood does not occur. The lesions are sessile or polypoidal, originate in the gut submucosa, vary greatly in cellularity, and have a wide range of tissue eosinophilia. Some are very vascular, many of the larger vessels having a notably broad zone of connective tissue about them. The aetiology of the condition is discussed and reasons for distinguishing it from eosinophilic gastroenteritis, with which it is frequently confused, are given. The precise nature and aetiology of the inflammatory fibroid polyp remains undetermined.

Fibrous inflammatory polyps of the ileum and cecum: review of five cases with emphasis on differentiation from mesenchymal neoplasm

Five case histories of patients with fibrous inflammatory polyps of the ileocecum are reported. Clinical impression in all five cases was that these tumefactions represented gastrointestinal malignancies. Gross pathologic examination revealed polypoid intramural growths ranging from 2.5 to 7.0 cm in greatest dimension. Transmural desmoplasia through the bowel wall into subserosal fat was initially thought to be indicative of neoplastic invasion. Microscopic evaluation revealed a fibroblastic and vascular proliferative process. Pseudosarcomatous changes were identified in cellular fibroblastic areas with plemorphism and mitotic activity. The manner of dissection among bundles of muscularis mucosae and muscularis propria suggests an inflammatory process as opposed to the pushing aside of whole large muscle bundles as seen in mesenchymal neoplasms arising in bowel wall. All five patients experienced survival of 6 to 17 years following surgery. These lesions are thought by us to represent localized exuberant polypoid granulation tissue proliferations which simulate mesenchymal neoplasm.

Inflammatory pseudotumors (inflammatory fibrous polyps) of the esophagus. A clinicopathologic study

When they involve the gastrointestinal tract, inflammatory pseudotumors, composed of inflamed fibrous and granulation tissue, produce localized, frequently polypoid, masses. These rare lesions have been described in the stomach, small intestine, and colon. Only two have been previously reported in the esophagus. In this paper, 4 cases of inflammatory pseudotumor involving the esophagus are presented. These lesions usually occur in the esophagus as raised, occasionally pedunculated, masses and may be mistaken on radiologic examination and in the operating room for a neoplasm, usually a leiomyoma. Theories concerning pathogenesis of these lesions are considered and the differential diagnostic criteria are discussed.

Inflammatory pseudotumors (inflammatory fibrous polyps) of the small intestine: A clinicopathologic study

The clinical and pathologic features of 25 inflammatory pseudotumors of the small intestine are reported. These rare lesions, which clinically may simulate neoplasms, consist of localized, frequently polypoid masses composed of inflamed fibrous and granulation tissue. Inflammatory pseudotumors may produce intussusception and small-bowel obstruction. Some are found at laparotomy performed for other reasons. The diagnosis of inflammatory pseudotumor usually can not be made until the lesion is examined histogically. Their etiology remains unknown, but their relationship to intestinal ulceration is discussed. Problems in differential histologic diagnosis are considered.

Gastric pseudolymphoma (lymphofollicular gastritis)

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