1. Department of Head and Neck Surgery, Kaiser Permanente Oakland Medical Center, Oakland, CA, USA
2. Department of Medicine, David Geffen School of Medicine at University of California, Los Angeles, CA, USA
3. Department of Surgery, University of California, Irvine Medical Center, Orange, CA, USA
4. Department of Surgery, University of Washington Medical Center, Seattle, WA, USA
5. Department of Dermatology, University of Colorado Anschutz Medical Campus, Aurora, CO, USA