This research is being done in order to improve treatment outcomes in patients diagnosed with bulky, early stage Hodgkin lymphoma and to reduce the side effects that are associated with use of radiation used in current treatments. The chemotherapy treatment in this study consists of a combination of four drugs approved by the Food and Drug Administration (FDA): doxorubicin, bleomycin, vinblastine, and dacarbazine. This regimen (called ABVD) has been found to be effective in treating patients with Hodgkin lymphoma and is considered the standard of treatment used with radiation therapy in patients with bulky early stage Hodgkin lymphoma. As part of the evaluation of the effectiveness of the chemotherapy treatment, PET scans will be obtained during the course of therapy. The usefulness of this PET scan will be evaluated to determine whether radiation may be left out in the treatment of disease if the PET scan shows that the patient has responded to chemotherapy alone. The plan is to identify a group of patients using early PET scans in order to change to a chemotherapy treatment called BEACOPP (bleomycin, etoposide, doxorubicin, cyclophosphamide, vincristine, procarbazine and prednisone). It is one of the most highly effective chemotherapy regimens for Hodgkin lymphoma, but is associated with more side effects than ABVD. Although it has become standard of care in Europe, its use has been more limited in the U.S. because of concerns about toxicity.