[595] Adenocarcinoma of the Small Intestine: A Multi-Institutional Study of 197 Cases

S-M Hong, E Yu, JH Kim, YK Bae, K-T Jang, H-K Chang, ES Jung, G-S Yoon, H-I Bae, JM Kim, Y-H Oh, GI Kim, SJ Jung, MJ Gu, JY Kim, KY Jang, S-Y Jun, DW Eom, KW Kwon, GH Kang, JB Park, SW Hong, JS Lee. Johns Hopkins Medical Institutions, Baltimore, MD; Korean Small Intestinal Cancer Study Group, Seoul, Korea

Background: Small intestinal adenocarcinoma (SIAC) is a rare malignant neoplasm and its clinicopathologic characteristics have not been systemically evaluated.
Design: A total of 197 SIAC cases were collected from 22 institutions in Korea, and were evaluated for clinicopathologic factors that affect prognosis of SIAC patients using univariate and multivariate analyses.
Results: Mean patient age was 59 and male to female ratio was 1.7:1. Tumors were located in the duodenum of 108 cases (54%), the jejunum in 56 (28%), the ileum in 29 (15%), and an unspecified site in 4 (3%). Predisposing conditions were observed in 23 cases (12%), including 17 cases with sporadic adenomas, 3 with Peutz-Jeghers syndrome, 2 with Meckel's diverticulum, and 1 with Crohn's disease. Synchronous or metachronous malignant tumors were identified in 31 cases (16%), including 13 colorectal and 10 stomach cancers. About 90% of tumors were either pT3 (108 cases) or pT4 (66 cases) classification. Median survival time for entire SIAC patients was 38.5 months. SIAC patients with accompanying adenomas tended to have a tumor with well-differentiation (P<0.001), a more polypoid growth pattern (P<0.001), a lower pT classification (P<0.001), less perineural (P=0.01) and lymphatic (P=0.04) invasion than those without adenomas. SIAC patients with adenomas (76.9%) had a significantly better 5-year survival rate than those without adenomas (37.2%, P=0.002). pT (P<0.001) and pN (P=0.001) classifications, location of tumor (P=0.001), vascular invasion (P=0.01), and radiation therapy (P=0.01) had significantly different patient survival by univariate analysis. By multivariate analysis, only pT (P=0.01) and pN (P=0.03) classifications remained significant prognostic factors.
Conclusions: 1) SIACs are diagnosed in advanced stage, therefore development of strategies for detection in earlier stages is required. 2) SIAC patients with adenomas have a better survival than those without adenomas. 3) Like other gastrointestinal tract tumors, pT and pN classifications are the most important prognostic factors.
Category: Gastrointestinal

Monday, March 9, 2009 1:00 PM

Poster Session II # 90, Monday Afternoon