Irinotecan and Cisplatin for High Grade Neuroendocrine Carcinoma of the Gastrointestinal Tract

Both irinotecan and carboplatin are drugs commonly used to treat cancer. Before treatment starts, patients will have blood tests (around 4 teaspoons) and urine tests. Patients will have a chest X-ray, an electrocardiogram (ECG-a test to measure the electrical activity of the heart), and a computed tomography (CT) scan. Women who are able to have children must have a negative blood pregnancy test. During the study, patients will receive irinotecan and cisplatin by vein over 4 hours, once a week for 2 weeks. This will be followed by 7 days in which no treatment will be given. This 3 week period is called a cycle. Cycles will be repeated unless the tumor continues to grow. During treatment, patients will have follow-up visits every 3 weeks to check for any side effects and the status of the disease. The follow-up visits may be with either your local doctor or with the study doctor. However, visits with the study doctor should be scheduled at least every 9 weeks. If the disease gets worse or you experience any intolerable side effects, you will be taken off the study. This is an investigational study. Both irinotecan and cisplatin are FDA approved and commercially available. Around 36 patients will participate in the study. All patients will be enrolled at M.D. Anderson.