812 Can the Frey Procedure Relieve Biliary Obstruction in Chronic Pancreatitis Without a Separate Drainage Procedure?

carcinoid was colorectal (28%), followed by the small intestine (20%), and stomach (6%). At the time of diagnosis 49%, 21%, and 23% of patients demonstrated localized disease, regional disease, and distant disease, respectively. A single synchronous lesion was noted in 17% of patients, and 3% had two synchronous lesions. The overall 5-year survival for patients was ~58%. 2) Of the patients with carcinoid tumors resected at our institution, there was a trend of increased expression of VEGF-R and IGF-R, particularly in the foregut and midgut carcinoids. CONCLUSIONS. Analysis of a large database representative of a comprehensive source of population-based information confirms that the incidence of carcinoid tumors is increasing with an approximate doubling in the number of carcinoid cases from 1990-2002. Furthermore, we demonstrate an increase in VEGF-R and IGF-R expression, particularly of- foregut carcinoids, suggesting that GFR inhibitors may be effective adjuvant therapy for carcinoid cancer and the associated fibrotic response. 812 Can the Frey Procedure Relieve Biliary Obstruction in Chronic Pancreatitis Without a Separate Drainage Procedure? H Ramesh, George Jacob Aim: To assess the feasibility of the Frey procedure in relieving biliary obstruction without a separate drainage procedure. Patients: The data of 79 patients with chronic pancreatitis and biliary obstruction (bile duct diameter>7 mm with abnormal liver function tests) who were treated surgically over an 8 year period was analyzed. Patients with cancer were excluded. 59 patients who underwent Frey procedure were included. Procedure: Initial cystic duct cholangiography was followed by adequate head coring, after which cholangiography was repeated. Further management was dependent on: a) Free flow of contrast into duodenum: no additional procedure: n=21 b) Extensive structuring of and confined to intrapancreatic common bile duct: longitudinal bile ductotomy and incorporation into the Roux-en-Y pancreaticojejunostomy (internal biliary drainage): n=28 c) Free flow of contrast, but deep jaundice, and/or cholangitis: additional short term (6 weeks) T tube drainage: n= 5 d) Stricture extending beyond intrapancreatic common bile duct: A. Healthy duodenum and CBD diameter ≥1.5 cm: side-to-side choledochoduodenostomy; n=4 b. Unhealthy, edematous duodenum with thick walled CBD: hepaticojejunostomy onto same loop of jejunum as pancreatic anatomosis: n=1 Results: follow up 36-124 months (see table) Conclusion: Frey procedure relieved biliary obstruction without an additional biliary drainage procedure. When stricturing was unrelieved by head coring, internal drainage of the bile duct into the pancreaticojejunostomy could be achieved without deleterious effects. Patient data and results

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SSAT Abstracts

Molecular Predictors of Response to Neoadjuvant Topotecan and Radiation for Rectal Cancer: Correlative Study to a Phase I Trial Alfredo A. Santillan, William Dinwoodie, Timothy J. Yeatman, Steven A. Eschrich, Daniel Sullivan, Caio S. Rocha-Lima, Harvey M. Greenberg, Catherine Chodkiewicz, Andy Trotti, Jorge Marcet, Sophie Dessureault, Philippe Legenne, Paul Wissel, Preeta Tyagi, David Shibata Introduction: Neoadjuvant chemoradiation (NCR) has become the preferred approach for locally advanced rectal cancer (RC). We have evaluated the use of oral topotecan as a radiosensitizing agent in this setting. In this study, by the use of gene expression profiling (GEP), we sought to assess molecular patterns associated with pathologic response to NCR. Methods: A phase I study design was used to determine the maximum tolerated dose of oral topotecan in combination with radiation in the neoadjuvant treatment of RC. Topotecan was administered orally for 25 doses with a starting dose of 0.25mg/m2 (max 1.15 mg/m2) in combination with standard radiation. All patients underwent tumor biopsy both before and during NCR treatment (between days 10-14). Pathologic response was determined after definitive radical surgery. All specimens underwent GEP using the Affymetrix U133 Plus 2.0 Gene chip and data were normalized using the Bioconductor software. Significant genes were identified by the t test. GeneGO MetaCore software was used to identify significantly altered biologic pathways. Results: From 2001 to 2007, 26 patients (Stage II n=18, III n= 8) participated in the study. The pathologic complete response (pCR) and non-response rate (NR, stable or progressive disease) were 19% (n=5) and 39% (n=10), respectively. A partial pathologic response was observed in 42% of patients (n=11). Comparing pre-treatment GEP between pCR and NR patients revealed 30 upregulated and 37 downregulated genes (p<0.001). Gene ontology analysis revealed 7 significantly enriched pathways. Of these, 6 were involved in nucleotide or lipid metabolism (e.g. CTP/UTP metabolism, p<0.001; plasmalogen metabolism, p<0.001) and 1 in apoptosis and survival (antiapoptotic TNFs/ NF-kB/IAP pathway, p=0.07). In an attempt to identify mid-treatment markers of subsequent response, we examined gene expression ratios from pre- and intra-treatment tissues. A total of 18 genes demonstrated differential upregulation in pCR cases and included genes associated with angiogenesis, apoptosis and transcriptional regulation (e.g. ANGPT1, NR1D1, LOC10012, EYA4 and PDCD2). Conclusions: Neoadjuvant topotecan and radiation yields pCR rates similar to those seen with standard 5-FU/radiation. Distinct molecular patterns were detectable in pretreatment biopsies that were associated with subsequent pathologic response. As a novel approach, we have also identified specific molecular changes that occur during treatment that may be predictive of a pCR. Our findings encourage further investigation of predictive genetic signatures as well as of biologic mechanisms associated with NCR treatment response. (Quickshot/Poster) 811

Selective biliary cannulation during ERCP opacifying pancreaticojejunostomy.

Population-Based Analysis and Growth Factor Receptor Expression of GI Carcinoid Tumors Kanika A. Bowen, Scott R. Silva, Taylor S. Riall, Hung Q. Doan, B. M. Evers

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Although still considered relatively uncommon, the incidence of carcinoid tumors appears to be increasing at a more rapid rate than other cancers. Surgical treatment of carcinoid tumors of the gastrointestinal (GI) tract can be particularly difficult due to the intense fibrotic response; multiple growth factors and their receptors are suspected to be involved in this process yet this aspect has not been studied in detail. The purpose of our study was twofold: 1) to determine the incidence, patient and tumor characteristics, synchronicity, and outcome of patients with GI carcinoid tumors using the Surveillance, Epidemiology and End Results (SEER) database, and 2) to delineate the expression pattern of growth factor receptors in carcinoid tumors. METHODS. 1) The SEER database search, which is comprised of cancer incidence and survival data from cancer registries covering approximately 26% of the US population, provided information on patients diagnosed with carcinoid tumors from 19902002. 2) Paraffin-embedded blocks of carcinoid tumors (n = 45) from the foregut, midgut, and hindgut were sectioned and stained for the following growth factor receptors (GFRs): epidermal growth factor receptor (EGF-R), insulin-like growth factor receptor (IGF-R), vascular endothelial growth factor receptor (VEGF-R), HER-2/neu, and neural cell adhesion molecule (NCAM). RESULTS: 1) Over the 12 year analysis period, 18,180 patients were identified with carcinoid tumors of the foregut, midgut, and hindgut; the incidence of carcinoid tumors increased ~2-fold during this time period. The most common site of GI

SSAT Abstracts

Immediate Versus Tailored Immunoprophylaxis After Surgery for Crohn's Disease (CD) Liliana Bordeianou, Sharon L. Stein, Vanessa P. Ho, Bruce E. Sands, Joshua R. Korzenik, Vinita E. Jacob, Brian P. Bosworth, Richard A. Hodin Introduction: Studies have not established timing of immunoprophylaxis (Rx) with 6-MP, azathioprine, or mesalamine after surgery for CD. Some suggest Rx should be initiated ≤1 month, others advocate targeted Rx at time of endoscopic recurrence. We compare efficacy of these competing approaches. Methods: 199 CD patients who underwent ileocecectomy 9/93 - 4/08 were retrospectively divided into 3 groups based on Rx timing: immediate (Irx), tailored (T-rx), none (N-rx) . Groups were compared for differences in demographics, pathology, surgical technique (chi square, ANOVA). Rate of symptomatic recurrence (chisquare), and time to symptomatic recurrence was analyzed (log rank, multivariate Cox proportional hazards). Results: 69 (34.7 %) received I-rx, 32 (16.1%) received T-rx and 98 (49.3%) were N-rx. The groups were similar, though I-rx were younger and N-rx more likely to be lost to follow-up (table). At 5-years, 62 (53.9%) patients had endoscopic, 46 (51.9%) had symptomatic and 22(24.3%) had surgical recurrences. On chi square, T-rx appeared more likely than I-rx to have symptomatic recurrence (43.7% vs. 28.9%, p=0.02),

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