An intra-abdominal solid-cystic desmoid that emerged after distal gastrectomy

Desmoid is a locally aggressive fibroblastic neoplasm, typically showing a heterogeneous solid mass, and its pathogenesis is multifactorial, including surgical scars. We herein report a rare case of an intra-abdominal desmoid, consisting of solid and cystic components covered with epithelial linings, that emerged after distal gastrectomy. The preoperative diagnosis was inconclusive, so laparotomy was performed. Histopathology of the solid component showed proliferating spindle cells, which were positive for beta-catenin in their nuclei. Clinicians need to bear in mind that desmoids can appear in a solid-cystic form, and immunostaining of beta-catenin should be applied for tumors that emerge around postoperative wounds.