POSTER SESSION V Wednesday, March 2, 2005   —  9:30 AM - 12:00 Noon Convention Center, Exhibit Hall B GASTROINTESTINAL PATHOLOGY 55 Clinicopathological Significance of the c-KIT and PDGFRa Gene Mutations in Patients with Localized Gastrointestinal Stromal Tumors: A Study of the Spanish Research Sarcoma Group (GEIS) (505) A Llombart-Bosch, JA Lopez-Guerrero, S Calabuig, J Martin, R Ramos, L Ortega, A Pellin - University of Valencia, Valencia, Spain; FIVO, Valencia, Spain; Hospital Son Dureta, Palma de Mallorca, Mallorca, Spain; Hospital Clinico San Carlos, Madrid, Spain 56 Protein Kinase C theta (PKC-q) Selective Expression in Gastrointestinal Stromal Tumors (GISTs) (513) R Miquel, A Gaspa, N Perez, A Mozos, P Blay, JM Freije, A Palacin, JA Bombi, T Ribalta, V Marco, J Miro, E Campo - Hospital Clinic, Barcelona, Spain; Instituto Universitario de Oncologia, Universidad de Oviedo, Oviedo, Spain; Hospital General de Catalunya, Barcelona, Spain; Clinica Girona, Girona, Spain 57 Wilms Tumor Gene Protein (WT-1) and Calretinin (Cal) Immunoreactivity in Gastrointestinal Stromal Tumor (GIST) (552) T Tsuzuki, K Hara, E Takahashi, N Maeda - Nagoya Daini Red Cross Hospital, Nagoya, Japan; Aichi Mededical University, Nagakute, Japan; Aichi Cancer Center, Naogya, Japan 58 Epidermal Growth Factor Receptor (EGFR) Protein, p53, and Cyclin D1 Expression in Colon Carcinoma: Correlation with EGFR Gene Amplification Using a Chromogenic In Situ Hybridization (CISH) Assay (438) RW Askeland, M Jans, C Bromley, MA Vasef - University of Iowa Hospitals and Clinics, Iowa City, IA 59 Activating Mutation of the EGFR Gene Is Rare and Not Responsible for Gefitinib Sensitivity in Colorectal Cancer (520) S Ogino, M Brahmandam, M Cantor, C Namgyal, T Kawasaki, M Loda, CS Fuchs - Brigham and Women's Hospital, Boston, MA; Dana-Farber Cancer Institute, Boston, MA; Harvard Medical School, Boston, MA 60 EGFR Immunohistochemical Expression in Microsatellite Stable and Unstable Colorectal Carcinomas (526) A Payá, C Alenda, FI Aranda, G Peiró, R Jover, B Massutí, A Yuste - Hospital General Universitario de Alicante; Hospital General Universitario de Alicante, Spain 61 Epidermal Growth Factor Receptor Expression and Gene Amplification in Colorectal Carcinoma: An Immunohistochemical and Chromogenic In Situ Hybridization Study (540) J Shia, D Klimstra, A Li, J Qin, J Teruya-Feldstein, M Akram, C Hedvat, W Gerald, B Chen - Memorial Sloan-Kettering Cancer Center, New York 62 Expression of Epidermal Growth Factor Receptor in Squamous Cell Carcinomas of the Anal Canal (436) G Alvarez, BR Tan, HL Wang - Washington University School of Medicine, St. Louis, MO 63 p16 and Ki67 Immunostaining Is a Useful Adjunct in the Assessment of Biopsies for HPV-Induced Anal Intraepithelial Neoplasia (AIN) (555) A Walts, J Lechago, S Bose - Cedars Sinai Medical Center, Los Angeles, CA 64 CD117 (c-Kit) in Anorectal Melanoma-A Potential Diagnostic Pitfall (445) O Ben-Izhak, V Dobiner, J Sandbank, G Groisman, E Sabo - Rambam Medical Center, Haifa, Israel 65 Morphologic and Immunohistochemical Features of Anorectal Melanoma (454) DJ Chute, JB Cousar, SE Mills - University of Virginia, Charlottesville, VA 66 The Diagnostic Value of Pancreatic-Duodenal Homeobox 1 (PDX-1) in Separating Metastatic Carcinoma of Unknown Origin (542) JF Silverman, C Deng, M Tung, D Medich, YL Liu - Allegheny General Hospital, Pittsburgh 67 Differential MLH1 Promoter Hypermethylation in the Identification of Sporadic Mismatch Repair-Deficient Colorectal Cancers (466) EJ Fox, DT Leahy, R Geraghty, AM Lennon, D Keegan, A White, HE Mulcahy, JM Hyland, D Fennelly, DP O'Donoghue, K Sheahan - Conway Institute of Biomolecular and Biomedical Research, University College Dublin, Dublin, Ireland; Centre for Colorectal Disease, St Vincent's University Hospital, Dublin, Ireland 68 Identification of Colorectal Adenocarcinomas with High-Level Microsatellite Instability Based on Age and Histopathologic Criteria (474) A Gologan, A Krasinskas, J Hunt, L Farkas, AR Sepulveda - University of Pittsburgh Medical Center, Pittsburgh, PA 69 Diagnostic Concordance and Role of Size and Site in the Identification of Sessile Serrated Adenomas (547) BA Stohr, LD Ferrell, YY Chen, GE Kim, S Kakar - Univ CA SF, San Francisco, CA 70 Frequent Gastric Differentiation in Colorectal Carcinoma with Microsatellite Instability (496) SF Kuan, AR Sepulveda - University of Pittsburgh, Pittsburgh, PA 71 Histologic Predictors of 5 Year Survival in 169 Patients with Right Sided Colon Cancer (560) J Willis, A Chak, B McGloin, K Sauder, SD Markowitz, GC Cooper - University Hospitals of Cleveland, Cleveland, OH; University Hospitals of Cleveland, Cleveland, OH; Case Comprehensive Cancer Center, Cleveland, OH 72 Colorectal Carcinoma in Iraq: Clinicopathological Study (434) RH Al-Hadithi, ZR Al-Bahrani, AZ Al-Bahrani - Al-Nahrain University College of Medicine, Baghdad, Iraq; Baghdad University- College of Medicine, Baghdad, Iraq 73 Invasive Micropapillary Carcinoma (MPC) of Colon: An Aggressive Variant of Colonic Adenocarcinoma (493) MJ Kim, SM Hong, SJ Jang, K-R Kim, GY Gong, JY Ro - University of Ulsan College of Medicine, Seoul, Republic of Korea 74 Additional Lymph Node Examination from Entire Submission of Residual Mesenteric Tissue (ESMT) in Colon Cancer Specimens May Not Add Clinical and Pathologic Relevance (494) YM Kim, JH Suh, HJ Cha, SJ Chang, M-J Kim, SO Yoon, BH Kim, HJ Chang, YM Kwon, EK Hong, JY Ro - Ulsan University Hospital, Ulsan, Korea; University of Ulsan College of Medicine, Asan Medical Center, Seoul, Korea; National Cancer Center, Ilsan, Korea 75 The Prognostic Significance of Intratumoral Neutrophils in Advanced Stage Colorectal Adenocarcinoma (537) CD Scopa, V Zolota, T Kourelis, T Makatsoris, D Kardamakis, H Kalofonos, AC Tsamandas - Univ. of Patras, Greece