1 Medical Oncology Department, Clínica Universidad Los Andes, Centro de Investigación Clínica Bradford Hill, Santiago, Chile. Electronic address: mauricioburotto@gmail.com.
2 Centro de Investigación Clínica Bradford Hill, Santiago Chile.
3 Medical Oncology Department, Hospital Clinico Universidad de Chile, Santiago, Chile.
4 Medical Oncology Department, Clinica Alemana, Santiago, Chile.
5 Department of Public Health, Pontificia Universidad Católica de Chile, Santiago, Chile.