Impact of 10 Different Prior Cancer Histories on Survival of Patients who Underwent Surgery for Second Primary Colorectal Cancer Based on Analysis of the SEER Database.

Cancer survivors newly diagnosed with second primary colorectal cancer (SPCRC) is rapidly growing. However, the impact of different prior cancers on survival of patients who underwent surgery for SPCRC remains unclear; therefore, we conducted an analysis to investigate the influence of prior cancer history. In this study, the data of patients diagnosed with CRC between 2004 and 2013 were extracted from the Surveillance, Epidemiology, and End Results database. The bias was minimized by Propensity Score Matching, and the Kaplan-Meier method as well as Cox proportional hazards models were used to analyze the impact of different prior cancer histories on overall survival (OS) and colorectal cancer-specific survival (CCSS) in patients undergoing surgery for SPCRC. Subgroup analyses were further conducted based on the time since first cancer diagnosis, age at SPCRC diagnosis, and SPCRC stage.Here, we included 68,410 patients who underwent surgery for FPCRC and 12,010 patients for SPCRC. KM curves showed that the OS and CCSS of patients with a history of prior thyroid cancer undergoing surgery for SPCRC were similar to those undergoing surgery for FPCRC (P ≥ 0.05). Patients with a history of prior colorectal cancer, prostate cancer, breast cancer, uterine cancer, bladder cancer, skin cancer, lung cancer, kidney cancer, or stomach cancer undergoing surgery for SPCRC had inferior OS compared to those undergoing surgery for FPCRC (P < 0.05). Taken together, our findings demonstrate that the history of prior cancers, except for prior thyroid cancer, might adversely influence the OS of patients who underwent surgery for SPCRC.