1. Departments of Medicine and Pathology, The University of Texas M. D. Anderson Hospital and Tumor Institute, Houston, Texas 77025.
2. The University of Texas M.D. Anderson Hospital, Houston, Texas 77025.
3. Princess Margaret Hospital, Toronto, Canada.
4. Assistant Professor of Pathology, The University of Texas M. D. Anderson Hospital.
5. The University of Texas M. D. Anderson Hospital.
6. Department of Medicine, The University of Texas M. D. Anderson Hospital.