A multidisciplinary approach to desmoid tumors. When intra-abdominal fibromatosis degenerates into an abscess, which is the right treatment?

Introduction: Desmoid tumors are rare benign tumors that originates in the fibrous sheath or musculo-aponeurotic structure. Histologically benign, they tends to invade locally and to be recurrent.

Presentation Of Case: We report a rare case of an intra-abdominal desmoid tumor in a patient affected by familial adenomatous polyposis, which degenerated into abscess. Male, 38 years, was hospitalized for abdominal pain, bowel obstruction and fever. The computed tomography showed a big dishomogeneous mass occupying the whole mesentery with internal massive liquefaction. The mass extended from the epigastrium for 13cm up to L3. On the right mesogastric side a solid, thick mass of about 2cm, with a length of 4.5cm, was identified; it was not cleavable from the wall and from some of the loops. We decided to perform a computed tomography-guided percutaneous drainage. Two hundred ml of purulent necrotic material was aspirated, and washing with antibiotic solution was carried out. Cytological examination of fluid drainage showed histiocytes and neutrophils. At follow-up, the patient's clinical condition had improved. An abdominal ultrasound showed a substantial reduction in the diameter of the mass.

Discussion: Diagnosis and treatment of desmoids tumor in patients with familial adenomatous polyposis may be difficult, especially when desmoids are located intra-abdominally and in the mesentery. Seldom will desmoid tumors be complicated by abscess formation.

Conclusion: The management of desmoids tumors is not easy and the choice of the best treatment may be difficult due to the different possible anatomical presentations.