Purpose The objective of this study was to examine the clincopathologic characteristics and outcomes of familial adenomatous polyposis (FAP) patients with and without desmoid tumors (DTs), including the risk factors for progression of FAP-related DTs. to as the curative resection group (eight patients), and the R2 resection/palliative operation/medical treatment group, referred to as the palliative resection group (10 patients). Two patients in the curative resection group and two patients in the palliative group had progressed to tumor growth by the follow-up (p=0.800). In univariate analysis, DT diagnosis before or simultaneously with FAP diagnosis (DTs unrelated to surgical trauma) was a significant risk factor for tumor progression at final follow-up. Conclusion A multidisciplinary approach to DT treatment is needed, including nonsteroidal antiinflammatory drugs, anti-estrogens, cytotoxic agents, and surgery. However, the role of surgery in resectable and complicated tumors may be limited. DT unrelated to surgical trauma has a relatively poor prognosis. gene on chromosome 5, and accounts for 1% or buy CEP-32496 hydrochloride less of all colorectal cancers (CRCs) . The risk of death due to CRC is decreased after prophylactic total proctocolectomy. Therefore, the extra-colonic manifestations of FAP are becoming more clinically significant . Among these, desmoid tumors (DTs) and periampullary cancers are currently the most common causes of death after CRC . DTs are poorly understood, frequently aggressive, tumors of mesenchymal origin, which arise in musculoaponeurotic structures. Intra-abdominal desmoids often appear to be surgically-induced, typically by prophylactic colectomy, but can arise in the absence of surgery . DTs are rare soft tissue tumors which can arise sporadically or in association with FAP. The DT is an extra-colonic manifestation of FAP. Despite their inability to metastasize, DTs are frequently locally invasive and may compress surrounding structures. In contrast to sporadic tumors, FAP-associated desmoids usually arise in the abdomen, and are a major cause of morbidity and mortality in patients who have undergone prophylactic colonic surgery. Despite recent research, they remain poorly understood entities, and current treatments generally lack evidence of efficacy. In the current study, we retrospectively examined the clincopathologic characteristics and outcomes of FAP patients with and without DTs, as well as the risk factors for progression of FAP-related DTs in patients undergoing surgical and pharmacological therapies in a single center. Materials and Methods 1. Patients We reviewed the medical records and database of all patients with FAP treated between January 1993 and December 2011 at Asan Medical Center, Seoul, Korea. The diagnosis of DT was established by a combination of clinical examination, surgical buy CEP-32496 hydrochloride exploration, and radiologic evaluation. A total of 75 FAP patients were evaluated. For each patient, the status of desmoid growth at the final follow-up was assessed and categorized according to either regression or stabilization of tumor growth or progression of tumor growth. 2. Statistical analysis Categorical variables were compared using chi-squared tests, and continuous variables were compared buy CEP-32496 hydrochloride using independent sample t-tests. The Kaplan-Meier method was used for comparison of overall survival rates. All statistical tests were two-sided, and p < 0.05 was considered statistically significant. Statistical analyses were performed using SPSS ver. 19.0 for Windows (SPSS, Inc., Chicago, IL). Results 1. Characteristics of FAP patients with and without desmoids Of the 75 patients, 18 (24%) were FAP with DTs. The characteristics of FAP patients with and without DTs are summarized in Table 1. The FAP with and without DT groups showed similar incidence of CRC (5 [27.8%] vs. 20 [35.1%], p=0.566). However, advanced stage CRC was more frequent in the FAP without DT group. Therefore, the main cause of deaths due to FAP without DTs was CRC-related ACVRLK4 (4/7, 57.1%), while deaths due to FAP with DTs were mainly desmoid-related. The two groups showed similar 5-year overall survival rates (88.9% in the FAP with DT group vs. 90.1% in the FAP without DT group, log rank=0.846) (Fig. 1). Fig. 1. Overall survival curves of familial adenomatous polyposis (FAP) with and without desmoid tumors. Table 1. Clinical characteristics of FAP with and without desmoids 2. Clinicopathologic characteristics of DT Seventeen of the 18 patients with DTs had intra-abdominal DTs and one had intra- and extra-abdominal DTs. The median age at time of diagnosis of DTs was 30 years (range, 20 to 48 years). Six of the 18 patients had multiple DTs. Two of the 18 patients were diagnosed with DTs before FAP diagnosis, and one was diagnosed with DT and FAP simultaneously. The median time between colectomy and DT diagnosis buy CEP-32496 hydrochloride in.