 This study will examine the safety and effectiveness of the experimental drug bevacizumab for treating both non-acquired immune deficiency syndrome AIDS and AIDS-associated Kaposis sarcoma KS. KS tumors depend on the formation of new blood vessels for their growth. Bevacizumab is an antibody to a protein called vascular endothelial growth factor VEGF that is produced by the body and is involved in blood vessel growth. Bevacizumab may block the action of VEGF, and thus help shrink KS lesions. 