ALAA AL- BAYOUK,RMT,MD,PhD. CONSULTANT & HEAD OF PATHOLOGY DEPT. NASSER MEDICAL COMPLEX

Case presentation

Personal data M.SH Female 36 years old

Clinical Huge abdominal mass Intestinal obstruction

Radiologcal USG CT - abdomen & pelvis Calcular GB Big mid & lower abdomen mesenteric lesion with mass effect suggesting sclerosing mesenteritis associated with inflammatory process without sizable collection.

Surgical Urgent exploratory laparotomy Transverse colon mass with internal abdominal wall involvement. En-bloc resection with extended right hemicolectomy

Pathology Gross Microscopy

Gross Muscular fascia 20x10 cm, Grayish, white glistening Colonic segment 100 cm /large mass 25x10 cm Adherent to bowel wall / serosa, not mucosal Muscular fascia 20x10 cm, Infiltrative borders Grayish, white glistening Firm homogenous Gritty sensation CS No hemorrhage No necrosis

Microscopy Spindled shaped fibroblasts, uniform Infiltrative margins Abundant collagen Myxoid matrix Vessels, delicate , compressed Lymphocytic infiltration No/ occ. mitosis Mild atypia No necrosis Serosa/ infiltation / Mucosa- LP (intact)

Approach Tumor ? Type ? B9 Malignant Primary Secondary Metastatic

Histology Epithelial Mesenchymal / Ct. Muscle Nervous

Provisional diagnosis Fibromatosis - superficial - Deep (DESMOID TUMOR)

Differential Diagnosis GIST strong CD117+, CD34+ Fibrosarcoma Low grade fibromyxoid sarcoma Leiomyoma Idiopathic retroperitoneal fibrosis Neurofibroma Shwannoma Sclerosing omentitis

Final Diagnosis MESENTERIC FIBROMATOSIS WITH INTESTINAL INVOLVEMENT. TRANSVERSE COLON MASS WITH ABDOMINAL WALL INVOLVEMENT, BIOPSY: MESENTERIC FIBROMATOSIS WITH INTESTINAL INVOLVEMENT. (INTRAABDOMINAL DESMOID TUMOR) . NO SIGNS OF MALIGNANCY .

Fibromatosis Abdominal Extra-abdominal Intra-abdominal Abdominal wall of women during or after pregnancy May see with cesarean section scar Extra-abdominal Outside abdomen and abdominal wall, usually in muscles of shoulder, chest wall, back and thigh, equal gender frequencies Intra-abdominal Mesenteric, pelvic or retroperitoneal locations, Often post-surgical

Fibromatosis Most patients present with asymptomatic abdominal mass which is large, measuring 10 cm or more. MF resembles gastrointestinal stromal tumors (GIST) that are mesenchymal neoplasms of the digestive tract and show a varied malignant potential.

Mesenteric fibromatosis (MF) Definition / General MF or intra-abdominal desmoid tumor is a rare proliferative disease affecting the mesentery. MF is a locally aggressive tumor that lacks metastatic potential, but the local recurrence is common.

Mesenteric fibromatosis (MF) Epidemiology The most common primary tumor of mesentery ~ 8 % of all fibromatosis Incidence of 2 - 4 per million population, less common than superficial fibromatosis Most cases are sporadic

Mesenteric fibromatosis (MF) Epidemiology May be familial (associated with Gardner's syndrome / FAP syndrome Clin Gastroenterol Hepatol 2008;6:215 Hyperestrogenic states

Mesenteric fibromatosis (MF) Epidemiology Related to trauma In a patient with a genetic predisposition, tissue injury like previous operation likely to be the cause

Fibromatosis Clinical features Usually ages 15 - 39 years, may be painful Seen in breast, colon , small bowel Common sites in children are head and neck May be fatal due to local effects, particularly in head and neck

Fibromatosis Treatment Excision with wide margins (Ann Surg Oncol 2009;16:1642) Inadequate excision may cause recurrence, less recurrence in abdominal wall than elsewhere but may recur 5 - 6 times May stop growing if stop excising, some recommend watchful waiting if asymptomatic or not growing (Expert Rev Anticancer Ther 2009;9:525)

Fibromatosis Treatment May respond to chemotherapy (J Clin Oncol2007;25:501) COX2 inhibitors (Urology 2007;70:591.e3), Imatinib / Gleevec (J Cancer Res Clin Oncol 2007;133:533), NSAIDs (World J Surg Oncol 2008;6:17), Radiation (Am J Clin Oncol 2005;28:211), Ramoxifen Watchful waiting (Eur J Surg Oncol 2008;34:462)

Fibromatosis Clinical features Stage: based on size, symptoms and complications Dis Colon Rectum 2008;51:897 Prognostic factors: age, tumor size, tumor site J Clin Oncol 2011;29:3553)

Case reports 27 year old woman with post-traumatic paraspinal mass (World J Surg Oncol 2008;6:28) 29 year old woman with tumor of abdominal wall (Radiology 2005;236:81) 29 year old woman with large desmoid tumor of the anterior abdominal wall (Internet J of Surg 2007;10:2) 30 year old man with aggressive mesenteric tumor that responded to chemotherapy (Jpn J Clin Oncol 2008;38:222) 43 year old woman with tumor of retroperitoneal space (World J Surg Oncol 2004;2:33)

Conclusion Treatment of mesenteric fibromatosis is a multidisiplinary approach

Conclusion Non- surgical treatment resulted in diverse & unpredictable outcome and it is considered to be an opportunity in patients with unrespectable lesions or for adjuvant therapy.

Conclusion Surgery has a key role in the management and radical resection with clear margins is the principal treatment of this tumor entity.

Take home message: Although intra-abdominal lesions with spindle cell morphology are relatively rare, and similarities in their clinical data, radiological and histopathological appearances may lead to misdiagnosis, it is also true that tumor diagnosis based on IHC staining or traditional criteria alone are not specific enough.

Take home message: Intra abdominal fibromatosis is benign and exclusively locally aggressive, where as GISTs, are malignant and potentially capable of leading to distant metastasis.