US Oncology Incorporated. The Group's principal activity is to provide comprehensive management services under long-term agreements to oncology practices related to diagnosis and outpatient treatment of cancer. The practices include medical oncology, radiation oncology, gynecologic oncology, stem cell transplantation, diagnostic radiology and clinical research. It develops, constructs and manages free standing cancer centers that provide treatment areas and equipment for medical oncology, radiation therapy and diagnostic radiology. It coordinates and manages cancer drug research trials for pharmaceutical and biotechnology companies. It also purchases and manages the inventory for cancer related drugs for affiliated practices.