Large desmoid tumors in familial adenomatous polyposis: a successful outcome

Desmoid tumors develop from connective tissue, fasciae, and aponeuroses, and may occur in the context of familial adenomatous polyposis or may arise sporadically; also, they may be extra-abdominal, intra-abdominal, or located in the abdominal wall. These benign tumors have a great aggressiveness with a high rate of local recurrence. We present the case of a 54-year-old woman with germline APC gene mutation, who underwent a total colectomy, subsequently developing two large infiltrative solid intra-abdominal lesions consistent with desmoid tumors. Medical treatment with Cox-2 inhibitors was initiated without result. She was submitted to resection for intestinal obstruction, but developed local recurrence. The lesions were also unresponsive to tamoxifen, and chemotherapy was initiated with dacarbazine plus doxorubicin, switching to vinorelbine plus methotrexate, achieving a good response in all lesions after 12 months. The approach to these intra-abdominal lesions should be progressive, beginning with observation, then a medical approach with non-steroidal anti-inflammatory drugs or with an anti-hormonal agent. Afterwards, if progression is still evident, chemotherapy should be started. Surgery should be reserved for resistance to medical treatment, in palliative situations, or for extra-abdominal or abdominal wall desmoid tumors.

Here, we describe a case of fibromatosis that developed within the capsule around a silicone breast implant treated with surgical excision alone. The patient remains recurrence free at 3 months post-operative magnetic resonance imaging.

The treatment paradigm in desmoid-type fibromatosis (DF) has changed in recent years from a surgery-based strategy to a multidisciplinary approach that includes systemic therapies. Among various medical therapies, hydroxyurea has been considered of potential interest. This case series summarizes the experience gained at four centers using hydroxyurea in relapsing DF. Hydroxyurea was given orally at an initial dose of 20 mg/kg/day (escalated up to 30 mg/kg/day as necessary, if well tolerated). The response rate was 18.7% major partial remissions, 37.5% considering any amount of shrinkage, 68.7% considering symptom response or signs of tissue response as well. In patients with no progression, the treatment was continued for 9-24 months. The response rate was moderate, but similar to that reported for other medical therapies currently considered as treatment options in this disease. Though further, larger series are needed to confirm as much, hydroxyurea has potential as an effective alternative therapy for DF.

A giant desmoid tumour required full thickness excision of the lower abdominal wall. The resultant massive defect was closed with reconstructive tissue matrix (Strattice). The mesh acted as successful scaffold for regenerative repair enabling skin grafting of a stable granulation bed giving a satisfactory mechanical and cosmetic result. This mesh should be explored further as a simpler alternative to complex plastic reconstructive techniques for large abdominal soft tissue defects.

A 17-year-old male reported swelling of his abdomen and abdominal pain. He was referred to our hospital with no history of surgery, trauma, or familial adenomatous polyposis. A large tumor in the abdominal cavity was detected by computed tomography, and surgical resection was performed. The tumor was thought to have developed from the anterior lobe of the transverse colon mesentery. It weighed 5.9?kg. Tumor cells with collagen fibers were observed in histopathological examination, but heteromorphism and the nuclear fission image were not apparent. Immunostaining revealed beta-catenin expression in the tumor cell nucleus. Diagnosis was an intra-abdominal desmoid tumor. Currently, there are no signs of recurrence. In this case, preoperative diagnosis was difficult, but surgery was the optimal treatment according to the symptoms.

Here we report the case of a 46-year-old patient with a desmoid-type fibromatosis (DF) mimicked a large cystic tumor in the retroperitoneum. Ultrasonography and computed tomography were performed in order to search for localizations and characteristics of the cystic tumor. Radiological findings showed an oval cystic mass with a relatively thick wall, measuring 18.3?×?12.3?×?21.5 cm in the left upper abdomen. Laparoscopic spleen-preserving distal pancreatectomy was performed and histopathological examination by immunohistochemical study enabled us to diagnose a DF invading the pancreatic parenchyma. The patient remained asymptomatic during an 8-month follow up period. DF can manifest as a mainly cystic mass with a thick wall, as in our case, which makes the correct diagnosis difficult. DF should be included in the preoperative differential diagnosis of a cystic retroperitoneal mass, regardless of its rarity.