1. Department of Medicine and Health Sciences, Universidad de Sonora, Hermosillo, México
2. Department of Surgery, Hospital General del Estado de Sonora, Hermosillo, México
3. GKT School of Medical Education, King's College London, London, UK
4. Cancer Center, The University of Arizona, Tucson, Arizona
5. Thoracic Surgery Department, Hospital +Querétaro, Querétaro, México