A 45 year-old man presented on Jan 28. 2004 to the emergency department with melena for three times and vomiting of blood Key information Problem Hypothesis RX 45 yr M ucer GI bleeding cancer varices drug-inducedA 45 year-old man presented on Jan. 28, 2004 to the emergency department with melena for three times and vomiting of blood. Key information Problem Hypothesis Rx 45 yr. M GI ulcer GI bleeding cancer varices drug-induced