Area Abbonati
LoginPassword
doi   10.1700/1053.11523
Tumori 2012;98(1):e13-e15




Ileal Vanek’s tumor mimicking cecal carcinoma
Antonio Piñero1, Pedro A García-Muñoz1, María J López2,
Jose A Ruiz-Maciá
2, Joaquín Sola2, and Jose A Pons3
1Department of Surgery, 2Department of Pathology, and 3Department of Digestive Diseases,
Mesa del Castillo Hospital, Murcia, Spain

Key words: inflammatory fibroid polyp, Vanek’s tumor, ileal tumor, carcinoembryonic antigen.

Acknowledgments: We are grateful to Dr Mike Tobin for his help in reviewing and translating the manuscript.

Correspondence to: Antonio Piñero, MD PhD, Mesa del Castillo Hospital, Ronda Sur 20, 30010 Murcia, Spain.
Tel +34-968-246116;
fax +34-968-234036;
e-mail antonio.pinero@carm.es

Received February 17, 2011;
accepted May 19, 2011.

abstract

Inflammatory fibroid polyps or Vanek’s tumors are rare benign pseudotumoral lesions  with morphological characteristics similar to those of submucosal mesenchymal tumors. They have been described in the gastrointestinal tract, most frequently in the gastric antrum. We present a case of ileal Vanek’s tumor associated with a raised carcinoembryonic antigen level and with radiological and endoscopic features mimicking cecal carcinoma.
Introduction
Subepithelial lesions are a heterogeneous group of digestive tract tumors which can be difficult to differentiate from malignant epithelial tumors but whose management and prognosis are very different. Submucous tumors account for less than 1% of all gastrointestinal neoplasms1. Eighty percent are gastrointestinal stromal tumors (GISTs), which arise from Cajal’s interstitial cells and are related to peristaltic activity. The remainder develop from other subepithelial tissues resulting in leiomyomas, schwannomas, lipomas, glomic tumors and their malignant variants2. There is also an even rarer group of submucous tumors that do not arise from the mesenchyma and that produce lesions such as carcinoid tumors, ectopic tissue, or inflammatory fibroid polyps (IFP). We present a patient with an unusual clinical presentation that illustrates the difficulty in differentiating between cecal carcinoma and this benign entity.
Case report
An asymptomatic 49-year-old man undergoing routine analysis was found to have a high level of carcinoembryonic antigen (CEA) (14 ng/mL, normal <5 ng/mL). Colonoscopy showed a 4-cm exophytic polypoid cecal mass, with histology revealing nothing more than inflammatory changes within normal colonic epithelium. Barium enema confirmed a cecal tumor (Figure 1) and abdominal ultrasonography reported a mass compatible with a cecal or appendicular tumor.
At laparotomy, a small bowel intussusception was seen with a polypoid ileal tumor being the precipitating lesion with no other abnormality. An ileocecal resection was performed and the macroscopic appearance was that of a 4-cm terminal ileal mass, 15 cm from the ileocecal valve. The patient made an unremarkable postoperative recovery and was discharged well.
Histological examination showed a well-demarcated non-ulcerated tumor with submucosal proliferation of mononuclear and monomorphic spindle and stellate cells in a fibromixoid stroma, with vascular proliferation and inflammatory infiltration dominated by mast cells and eosinophils. Immunohistochemistry gave negative results for S-100, ALK and CEA, and only mast cells were positive for CD117 (c-kit). The tumor showed a diffuse positive pattern for vimentin and focal positive expression of cyclin D1, and the perivascular stromal cells stained positive for CD34 (Figure 2). At follow-up 6 months following discharge, the patient remained well with normal CEA.



Discussion
IFP or Vanek’s tumor is a benign pseudotumoral lesion that has morphological features similar to those of submucosal mesenchymal tumors. It consists of cells reminiscent of fibroblasts, inflammatory eosinophilic infiltrate, collagenous fibrils, and abundant vasculature. These features were described by Vanek in 6 gastric tumors3. IFPs seem to occur most frequently between the fifth and seventh decades and can be found throughout the gastrointestinal tract but most commonly in the gastric antrum (70%) and ileum (20%), and rarely in the duodenum or jejunum4,5. They can be distinguished from GISTs and inflammatory myofibroblastic tumors because these 2 tumors show immunohistochemical positivity for CD117 and smooth muscle actin, respectively.
The reactive rather than neoplastic nature of the lesion is suggested by its low mitotic activity, low recurrence rate, absence of necrosis, and absence of metastases. Although Vanek initially suggested an allergic etiology because of the presence of eosinophils, its etiopathogenesis is not clear and a form of reparative tissue response to injury has been suggested6. It is not, however, a clearly defined pseudotumor and it is possible that 2 histogenetically different lesions exist: CD34-positive typical Vanek’s tumors and less typical CD34-negative lesions that may be related to inflammatory myofibroblastic tumors7. Other authors8 have studied overexpression of cyclin D1 in these tumors and they concluded that the stromal cells derive from dendritic cells with myofibroblastic differentiation and a possible defect in cell cycle regulation. Small bowel obstruction secondary to intussusception is the most frequent clinical presentation described in the literature9-11 and its presentation as an isolated finding of raised CEA in an asymptomatic individual has not been previously reported. The CEA level increase should be related to its expression by the epithelial component of the tumor, although, as in other diseases12, the source of CEA production at the cellular level has not been elucidated.




References
 1. Nowain A, Bhakta H, Pais S, Panel G, Verma S: Gastrointestinal stromal tumors: clinical profile, pathogenesis, treatment strategies and prognosis. J Gastroenterol Hepatol, 20: 818-824, 2005.
 2. Stupnik S, Rafaelli C, Osorio-González G, Luján-Pestalardo M, Quesada M, Viudez P: Tumores subepiteliales del tracto gastrointestinal. Acta Gastroenterol Latinoam, 39: 118-124, 2009.
 3. Vanek J: Gastric submucosal granuloma with eosinophilic infiltration. Am J Pathol, 25: 397-412, 1949.
 4. Wysocki AP, Taylor G, Windsor JA: Inflammatory fibroid polyps of the duodenum: a review of the literature. Dig Surg, 24: 162-168, 2007.
 5. Gara N, Falzarano JS, Limm WML, Namiki TS, Tom LKS: Ileal inflammatory fibroid polyp causing chronic ileocolic intussusception and mimicking cecal carcinoma. World J Gastrointest Oncol, 15: 89-92, 2009.
 6. De Petris G, Leung ST: Pseudoneoplasms of the gastrointestinal tract. Arch Pathol Lab Med, 134: 378-392, 2010.
 7. Daum O, Hes O, Vanecek T: Vanek’s tumor (inflammatory fibroid polyp). Report of 18 cases and comparison with three cases of original Vanek’s series. Am Diagn Pathol, 7: 337-347, 2003.
 8. Pantanowitz L, Antonioli DA, Pinkus GC, Shahsafaei A, Odze RD: Inflammatory fibroid polyps of the gastrointestinal tract: evidence for a dendritic cell origin. Am J Surg Pathol, 28: 107-114, 2004.
 9. Malik KA, Pande GK, Aftab Z, Nirmala V: Inflammatory fibroid polyp of the ileum causing intussusception. Saudi Med J, 26: 995-998, 2005.
10. Karamercan A, Kurukahvecioglu O, Yilmaz TU, Aygencel G, Aytac B, Sare M: Adult ileal intussusception: an unusual emergency condition. Adv Ther, 23: 163-168, 2006.
11. Costamagna D, Erra S, Zullo A, Sevente G, Durando R: Small bowel intussusception secondary to inflammatory fibroid polyp of the ileum: report of a case. Chir Ital, 60: 323-327, 2008.
12. Gakiopoulou H, Litsiou E, Valaris K, Balafoutas D, Patsouris E, Tseleni-Balafouta S: Possible association of CEA expression with oxyphilic change but not with C-cell hyperplasia in Hashimoto’s thyroiditis. Endocr J, 57: 693-699, 2010.