The tumor characteristics, treatment strategy, and prognosis in colorectal cancer patients with synchronous liver metastasis in China and the USA

Purpose This study performed an analysis of clinicopathological characteristics, surgical treatment strategy, and survival for CRC patients with LM between China and the USA. Methods The CRC patients with simultaneous LM were identified from the Surveillance, Epidemiology, and End Results (SEER) registry and the Chinese National Cancer Center (CNCC) database from 2010 to 2017. We assessed 3-year cancer-specific survival (CSS) according to surgical treatment strategy and time period. Results Differences in patient age, gender, primary tumor location, tumor grade, tumor histology, and tumor stage were observed between the USA and China. Compared to the USA, a larger proportion of patients in China underwent both primary site resection (PSR) and hepatic resection (HR) (35.1% vs 15.6%, P < 0.001), and fewer patients underwent only PSR in China (29.1% vs 45.1%, P < 0.001). From 2010 to 2017, the proportion of patient who underwent both PSR and HR has increased from 13.9% to 17.4% in the USA and from 25.4% to 39.4% in China. The 3-year CSS were increasing over time in both the USA and China. The 3-year CSS of patients receiving HR and PSR were significantly higher than those receiving only PSR and patients treated with no surgery in the USA and China. There were no significant differences of 3-year CSS between the USA and China after adjustment ( P = 0.237). Conclusions Despite the distinctions of tumor characteristics and surgical strategy in patients with LM between the USA and China, increased adoption of HR has contributed to the profound improvements of survival during recent decade.