Vanek Tumor (Inflammatory Fibroid Polyp) of the Ileum in Patient with von Recklinghausen Disease (Neurofibromatosis)

Figure 1. Vanek Tumor (Inflammatory Fibroid Polyp) of the Ileum. A. Lesion protruding through ilecocecal valve. B. Pseudopolypoid lesion with mucosal surface lceration. C. There is no specific pit pattern for these lesions. The main characteristics are their polypoid, fingerlike shape with irregular mucosa and surface ulceration.

Inflammatory fibroid polyp (IFP) or Vanek’s tumor is a rare, usually solitary and intraluminal polypoid benign tumor that can affect any part of the gastrointestinal (GI) tract, although in most cases it affects the stomach (1-5). Inflammatory fibroid polyp (IFP) was first described by Vanek in 1949 as a ‘submucosal granuloma with eosinophilic infiltration’ (2). IFP is characterized by proliferation of highly vascular fibrous tissue and infiltration by a variable number of different inflammatory cells (1, 3). Its etiology is unknown.

A plethora of different names have been suggested to describe IFP, such as eosinophilic granuloma, granuloblastoma or gastric fibroma with eosinophilic infiltration, granuloma with eosinophils, hemangiopericytoma, inflammatory fibroid tumor, and inflammatory pseudotumor (1, 3, 4). There is a possible association of IFP or a variant of IFP with neurofibromatosis (NF1) (NF1 = von Recklinghausen disease with pheochromocytoma) (4, 5). Indeed, gastrointestinal "juvenile-like (inflammatory/hyperplastic) mucosal polyps" (JLIHMPs) have been proposed as a neurofibromatosis type 1 (NF1)-specific gastrointestinal manifestation (4, 5). Juvenile polyposis syndrome (JPS) has also been reported in a NF1 patient, harboring concurrent NF1 and SMAD4 germline mutations. Additionally, NF1-like cafe-au-lait spots have been described in biallelic mismatch repair deficiency, another condition featuring gastrointestinal polyps. The SMAD4 and BMPR1A genes that are involved in 50-60% of JPS cases have not been investigated in the ~ 20 published cases of NF1-associated JLIHMPs except for the abovementioned patient with concomitant JPS and NF1 (5). However, incidental associations between NF1 and gastrointestinal polyposes at risk for gastrointestinal carcinoma should not be overlooked, given their implications in terms of clinical surveillance (5).

In sum, this case expands on the existing knowledge on IFP (Vanek tumor). We show the characteristic endoscopic appearance and add another case associated with neurofibromatosis.

References

1. Vanek J. Gastric submucosal granuloma with eosinophilic infiltration. Am J Pathol 25(3): 397-411, 1949. PMID: 18137133.

Garmpis N, Damaskos, C, Garmpi A, et al. In Vivo January 2021, 35 (1) 81-93; DOI: https://doi.org/10.21873/invivo.12235

Goto K, Hirosaki T, Masubuchi M. Neurofibromatosis Type 1-Associated Inflammatory Polyp of the Gastrointestinal Tract. Int J Surg Pathol. 2017 Feb;25(1):65-68. doi: 10.1177/1066896916648772. Epub 2016 Jul 28. PMID: 27170677. The entity known as "juvenile-like (inflammatory/hyperplastic) mucosal polyps of the gastrointestinal tract in neurofibromatosis type 1 (NF1)" was recently proposed, but is not well known. Here, we describe the characteristics of this entity in a surgically resected case. The hemorrhagic 2 × 1 cm-sized polyp was resected from the ascending colon of a 55-year-old male NF1 patient. The polyp was composed of characteristic multiple mucosal protrusions and submucosal elements that included vasculopathic changes. Histologically, this lesion was similar to an inflammatory fibroid polyp rather than juvenile or hyperplastic polyps. This disease could be a distinct entity, and "inflammatory vasculopathic polyp" would be a suitable name.

Ravegnini G, Quero G, Sammarini G, Giustiniani MC, Castri F, Pomponi MG, Angelini S, Alfieri S, Genuardi M, Zamboni G, Ricci R. Gastrointestinal juvenile-like (inflammatory/hyperplastic) mucosal polyps in neurofibromatosis type 1 with no concurrent genetic or clinical evidence of other syndromes. Virchows Arch. 2019 Feb;474(2):259-264. doi: 10.1007/s00428-018-2462-6. Epub 2018 Oct 1. Erratum in: Virchows Arch. 2019 Feb;474(2):265. doi: 10.1007/s00428-018-2472-4. PMID: 30276464.

Enea D, Dray X, Guillerm E, Guilloux A, Yver M, Cervera P, Svrcek M. Inflammatory/juvenile-like polyps in neurofibromatosis type 1 associated with epithelial dysplasia. Virchows Arch. 2024 May;484(5):865-868. doi: 10.1007/s00428-024-03769-w. Epub 2024 Feb 24. PMID: 38396165.