1. Facultad de Medicina, Universidad Peruana Cayetano Heredia, Lima 15102, Peru
2. Division of Orthopaedic Oncology, Department of Orthopaedic Surgery, Massachusetts General Hospital, Harvard Medical School, Boston, MA 02115, USA
3. College of Arts and Sciences, Boston University, Boston, MA 02215, USA
4. Miami Cancer Institute, Division of Orthopedic Oncology, Baptist Health System South Florida, Plantation, FL 33324, USA