1. Department of Medicine, Koo Foundation Sun Yat‐Sen Cancer Center, Taipei, Taiwan. R. O. C
2. Department of Pathology, Koo Foundation Sun Yat‐Sen Cancer Center, Taipei, Taiwan. R. O. C
3. Department of Surgery, Koo Foundation Sun Yat‐Sen Cancer Center, Taipei, Taiwan. R. O. C
4. Department of Radiation Oncology, Koo Foundation Sun Yat‐Sen Cancer Center, Taipei, Taiwan. R. O. C
5. Department of Medicine, Duke University Medical Center, Durham, NC, U. S. A.