Patients with T cell and B cell lymphoreticular malignancies bearing the cell surface antigen CDS will be evaluated prior to monoclonal antibody therapy to confirm the reported tumor cell findings. The peripheral blood lymphoid cells will then be immunophenotyped by flow cytometry and the phenotype will be monitored prior to and at intervals immediately post monoclonal antibody therapy. Particular attention to be paid to the lymphoid population distribution and the status of CDS. The patients are then studied daily for one week, weekly for the next month, and then periodically after that time.