An Analysis of Trends and Growth Factor Receptor Expression of GI Carcinoid Tumors

Introduction The purpose of our study was twofold: (1) to determine the incidence, patient and tumor characteristics, and outcome of patients with gastrointestinal carcinoid tumors using the Surveillance, Epidemiology and End Results (SEER) database, and (2) to delineate the expression pattern of growth factor receptors (GFRs) in carcinoid tumors. Materials and methods The SEER database search provided information on patients diagnosed with carcinoid tumors from 1990 to 2002. Carcinoid tumor sections (n=46) were stained for the GFRs: epidermal growth factor receptor, insulin-like growth factor receptor (IGFR), vascular endothelial growth factor receptor (VEGFR), and HER-2/neu. Results 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 similar to 2-fold during this time period. Of the patients with carcinoid tumors, there was a trend of increased expression of VEGFR and IGFR, particularly in the foregut and midgut carcinoids. Analysis of the SEER database confirms that the incidence of carcinoid tumors is increasing with an approximate doubling in the number of carcinoid cases from 1990 to 2002. Furthermore, an increase in VEGFR and IGFR expression suggests that GFR inhibitors may be effective adjuvant therapy for carcinoid cancer.