Vinblastine, Celecoxib, and Combination Chemotherapy in Treating Patients With Newly-Diagnosed Metastatic Ewing's Sarcoma Family of Tumors

RATIONALE: Drugs used in chemotherapy, such as vinblastine, work in different ways to stop tumor cells from dividing so they stop growing or die. Celecoxib may stop the growth of Ewing's sarcoma by stopping blood flow to the tumor. Combining more than one chemotherapy drug with celecoxib may kill more tumor cells. PURPOSE: Phase II trial to study the effectiveness of combining low-dose vinblastine and celecoxib with standard regimens of combination chemotherapy in treating patients who have newly-diagnosed metastatic Ewing's sarcoma family of tumors.