RATIONALE: Vandetanib may stop the growth of tumor cells by blocking some of the enzymes needed for cell growth and by blocking blood flow to the tumor. Drugs used in chemotherapy, such as oxaliplatin and docetaxel, work in different ways to stop the growth of tumor cells, either by killing the cells or by stopping them from dividing. It is not yet known whether vandetanib is more effective than a placebo when given together with oxaliplatin and docetaxel in treating advanced cancer of the esophagus or gastroesophageal junction.