J Cancer 2020; 11(12):3567-3579. doi:10.7150/jca.43518 This issue
1. Department of Oncology, The First Affiliated Hospital of Anhui Medical University, Hefei, Anhui Province 230000, China
2. Department of Pathology, The First Affiliated Hospital of Anhui Medical University, Hefei, Anhui Province 230000, China
3. Department of Radiology, The 901st Hospital of the Joint Logistics Support Force of PLA, Hefei, Anhui Province 230031, China
4. Department of Epidemiology and Biostatistics, School of Public Health, Anhui Medical University, Hefei, Anhui Province 230000, China
*These authors contributed equally to this work.
Objectives: Most patients with stage IV colon cancer did not have the opportunity for curative surgery, only selected patients could benefit from surgery. This study aimed to determine whether surgery on the primary tumor (SPT) should be performed in patients with stage IV colon cancer and how to select patients for SPT.
Methods: This study included 48,933 patients with stage IV colon cancer who were identified in the Surveillance, Epidemiology and End Results (SEER) database between 1998 and 2015. Propensity score matching (PSM) analysis was adopted to balance baseline differences between SPT and non-surgery groups. Kaplan-Meier (K-M) curves were utilized to compare the overall survival (OS). Prognostic nomograms were generated to predict survival based on pre- and post-operative risk factors. Patients were divided into low, middle, and high mortality risk subsets for OS by X-tile analyses based on scores derived from above nomograms.
Results: Patients with SPT had a significantly longer OS than those without surgery, regardless of the metastatic sites and diagnostic years. Nomograms, according to the pre- and post-operative risk factors, showed moderate discrimination (all C-indexes above 0.7). Based on X-tile analyses, low mortality risk subset (post-operative score ≤ 22.3, preoperative score ≤ 9.7) recommended for SPT, and high mortality risk was not.
Conclusions: SPT led to prolonged survival in stage IV colon cancer. Our nomograms would help to select suitable patients for SPT.