CASE REPORT Cytoreductive strategy for multiple intra-abdominal and abdominal wall desmoid tumors in familial adenomatous polyposis: report of three cases Koji Tanaka • Yuji Toiyama • Yoshinaga Okugawa • Junichiro Hiro • Aya Kawamoto • Yasuhiro Inoue • Keiichi Uchida • Toshimitsu Araki • Yasuhiko Mohri • Masato Kusunoki Received: 24 May 2012 / Accepted: 25 August 2012 / Published online: 8 September 2012 Ó Springer 2012 Abstract Desmoid tumors (DTs) are benign myofibrob- lastic neoplasms originating from the fascia or muscle aponeurosis, which occur in one-third of patients with familial adenomatous polyposis (FAP). Most FAP-associ- ated DTs occur in the intra-abdominal or abdominal wall region, thus, their infiltrative or expansive growth causes life-threatening organ damage, such as intestinal obstruc- tion, urethral obstruction, and mesenteric infiltration with the involvement of mesenteric vessels. Treatments including surgical resection, cytotoxic chemotherapy, nonsteroidal anti-inflammatory drugs and anti-estrogen therapy have all been tried with variable success. Here, we report on three patients with FAP who developed multiple intra-abdominal and abdominal wall DTs after total proc- tocolectomy and ileal pouch–anal anastomosis. Two cases underwent surgical resection of uncontrolled abdominal wall DTs after successful control of intra-abdominal DTs by systemic chemotherapy. The remaining case underwent repeated surgical resections of multiple intra-abdominal and abdominal wall DTs, and consequently had recurrent intra-abdominal DTs, with involvement of the small bowel and ureter. Surgical intervention as tumor volume reduc- tion (cytoreduction) may be useful for cases with medical treatment-refractory or symptomatic FAP-associated abdominal DTs. Keywords Cytoreduction Á Desmoid tumor Á Familial adenomatous polyposis Introduction Familial adenomatous polyposis (FAP) is a dominantly inherited cancer predisposition syndrome, leading to a nearly 100 % cancer risk by the age of 40 years. Patients with FAP also show extracolonic manifestations, including duodenal cancer and desmoid tumors (DTs) [1]. DTs are aggressive or desmoid-type fibromatoses and benign myofibroblastic neoplasms originating from the fascia or muscle aponeurosis, which occur sporadically or associated with FAP [2]. DTs occur as one of the extracolonic manifestations in 10–30 % of patients with FAP [3, 4]. The anatomical locations of DTs are the intra- abdominal region (80 %), followed by the abdominal wall (10–15 %) and the extra-abdominal region (5 %) [5]. FAP-associated abdominal DTs, especially intra- abdominal DTs, grow either infiltratively or expansively, resulting in the infiltration, displacement, compression and destruction of vital organs, although they grow slowly and do not metastasize. The clinical behavior of FAP-associ- ated abdominal DTs is considered as malignant, because they may cause life-threatening organ damage, such as intestinal obstruction, urethral obstruction, and mesenteric infiltration with the involvement of mesenteric vessels [6]. Treatments for DTs, including surgical resection, cytotoxic chemotherapy, nonsteroidal anti-inflammatory drugs, and anti-estrogen therapy have all been tried with variable success, although the optimal therapeutic strategy remains a matter of debate [7, 8]. Here, we report on three patients with FAP who developed multiple intra-abdominal and abdominal wall K. Tanaka (&) Á Y. Toiyama Á Y. Okugawa Á J. Hiro Á A. Kawamoto Á Y. Inoue Á K. Uchida Á T. Araki Á Y. Mohri Á M. Kusunoki Department of Gastrointestinal and Pediatric Surgery, Mie University Graduate School of Medicine, 2-174 Edobashi, Tsu, Mie 514-8507, Japan e-mail: qouji@clin.medic.mie-u.ac.jp 123 Clin J Gastroenterol (2012) 5:361–366 DOI 10.1007/s12328-012-0330-5