Abstract
BACKGROUND: Desmoid tumors (DT) are locally advanced but histologically benign monoclonal neoplasms that can occur from any musculoaponeurotic structure. The aim of this report is to analyze a rare clinical case of an aggressive intra-abdominal DT successfully treated with sorafenib. CASE SUMMARY: A 36-year-old man presented with increasing colicky abdominal pain and a self-palpable mass in his left abdomen. Fourteen years earlier he was diagnosed with a large intra-abdominal tumor, which adhered to the left colonic flexure, part of the major gastric curvature and the spleen. Subsequent exploratory laparotomy revealed a voluminous mass in the epigastrium, arising from the posterior surface of the stomach and invading the superior mesenteric vessels, transverse mesocolon and the small bowel mesentery. As the tumor was unresectable, a jejunojejunal bypass was performed. Traditional therapeutic interventions proved insufficient, and the patient was started on sorafenib with a subsequent full-disease response. CONCLUSION: DT's pathogenesis has been associated with mutations in the adenomatous polyposis coli (APC) gene or beta-catenin gene CTNNB1, sex steroids or previous surgical trauma. Local treatment modalities, such as surgery or radiotherapy, are implemented in aggressively progressing or symptomatic patients. Sorafenib is a hopeful therapeutic option against DTs, while several pharmacological agents have been successfully used.