 Patients undergo blood sample collection periodically for immunologic studies. Samples are examined for functional CD4 and CD8 immune response of patients by cytokine fluorescent cytometry; enumeration of pp65 antigen-specific CD8 T cells by tetramer analysis; antigen-induced T-cell proliferation; cytokine secretion and quantitative anti-pp65 antibody concentration in the serum by ELISA; and CMV pp65 quantitation in genomic DNA by reverse transcriptase-polymerase chain reaction. Patients may also undergo stereotactic biopsy or tumor resection to confirm tumor progression histologically and to assess immunologic cell infiltration and pp65 antigen escape at the tumor site by immunohistochemistry and polymerase chain reaction. 