Causal Model of Survival After Pulmonary Metastasectomy of Colorectal Cancer: A Nationwide Prospective Registry  Raul Embun, MD, Juan J. Rivas de Andrés, MD, FETS, Sergi Call, MD, FETS, Beatriz de Olaiz Navarro, MD, PhD, Jorge L. Freixinet, MD, PhD, Sergio Bolufer, MD, Jose R. Jarabo, MD, PhD, Nuria Pajuelo, BS, Laureano Molins, MD, PhD Juan J. Rivas, Laureano Molins, Raul Embun, Francisco Rivas-Doyague, Raul Embun, Jorge Hernández-Ferrández, Félix Heras, Javier de la Cruz, Matilde Rubio, Esther Fernández, Miguel Carbajo, Rafael Peñalver, José R. Jarabo, Diego González-Rivas, Sergio Bolufer, Carlos Pagés, Sergi Call, David Smith, Richard Wins, Antonio Arnau, Andrés Arroyo, Carmen Marrón, Akiko Tamura, Montse Blanco, Beatriz de Olaiz, Gemma Muñoz, José M. García Prim, Carlos Rombolá, Santiago García-Barajas, Alberto Rodríguez-Fuster, Jorge L. Freixinet, Javier Ruiz-Zafra, Guillermo Carriquiry, Moisés Rosenberg, Emilio Canalís Raul Embun, MD, Juan J. Rivas de Andrés, MD, FETS, Sergi Call, MD, FETS, Beatriz de Olaiz Navarro, MD, PhD, Jorge L. Freixinet, MD, PhD, Sergio Bolufer, MD, Jose R. Jarabo, MD, PhD, Nuria Pajuelo, BS, Laureano Molins, MD, PhD Juan J. Rivas, Laureano Molins, Raul Embun, Francisco Rivas-Doyague, Raul Embun, Jorge Hernández- Ferrández, Félix Heras, Javier de la Cruz, Matilde Rubio, Esther Fernández, Miguel Carbajo, Rafael Peñalver, José R. Jarabo, Diego González-Rivas, Sergio Bolufer, Carlos Pagés, Sergi Call, David Smith, Richard Wins, Antonio Arnau, Andrés Arroyo, Carmen Marrón, Akiko Tamura, Montse Blanco, Beatriz de Olaiz, Gemma Muñoz, José M. García Prim, Carlos Rombolá, Santiago García-Barajas, Alberto Rodríguez-Fuster, Jorge L. Freixinet, Javier Ruiz-Zafra, Guillermo Carriquiry, Moisés Rosenberg, Emilio Canalís  The Annals of Thoracic Surgery  Volume 101, Issue 5, Pages 1883-1890 (May 2016) DOI: 10.1016/j.athoracsur.2015.12.017 Copyright © 2016 The Society of Thoracic Surgeons Terms and Conditions

Fig 1 Graphic representation of the cumulative hazard function for each variable of the survival model: disease-free interval (DFI) of ≤12 months (blue line) or >12 months (green line), carcinoembryonic antigen (CEA) level ≤5 ng/mL (blue line) or >5 ng/mL (green line), laterality (unilaterality, blue line; bilaterality, green line), and pN status (NX-0, blue line; N1-2, green line). The x-axis represents the time (months) elapsed from the first pulmonary metastasectomy date to the final event (death/censured). The y-axis represents the logarithm of the cumulative hazard function ln [–ln(S)], with S = survival function. The parallel distribution of the curves over time supports the assumption of hazard proportionality. (LML = log minus log.) The Annals of Thoracic Surgery 2016 101, 1883-1890DOI: (10.1016/j.athoracsur.2015.12.017) Copyright © 2016 The Society of Thoracic Surgeons Terms and Conditions

Fig 2 Verification of the log-linear hypothesis through the graphic representation of residuals. The x-axis stands for the patients, and the y-axis represents the differences between the observed and expected values. Each dot symbolizes a patient. The fact that residuals are well balanced around the origin allows us to verify the log-linear hypothesis. (CEA = carcinoembryonic antigen.) The Annals of Thoracic Surgery 2016 101, 1883-1890DOI: (10.1016/j.athoracsur.2015.12.017) Copyright © 2016 The Society of Thoracic Surgeons Terms and Conditions