[A Case of Familial Adenomatous Polyposis with a Desmoid Tumor Probably Communicating to the Intestinal Lumen That Was Successfully Treated with Non-Surgical Therapy].

A 44-year-old man with familial adenomatous polyposis underwent laparoscopic-assistedtotal proctocolectomy with ilealpouch anal anastomosis(IPAA). Computed tomography conducted 21 months after IPAA demonstrated bilateral hydronephrosis andan intra-abdominal mass with a maximal diameter of 22 cm, leading to a diagnosis of stage IV desmoid disease, according to the classification by Church and associates. Six courses of combination chemotherapy with doxorubicin plus dacarbazine were administered. Computed tomography after chemotherapy demonstrated marked shrinkage of the desmoidtumor with intraabdominal air andfluidcollection extending just below the skin of the ileostomy closure site. Stoollike fluidoverflowedspontaneously through the site of the ileostomy closure andthe abscess cavity was successfully drained. The patient was discharged 30 days after the start of drainage. The patient is doing well 10 months after the drainage without regrowth of the desmoid tumor, even though a cavity-like lesion encapsulatedby a thick wall remains.