BACKGROUND Approximately one third of all patients with CRC present with, or subsequently develop, colorectal liver metastases (CRLM). The objective of this population-based analysis was to assess the impact of resection of liver only, lung only and liver and lung metastases on survival in patients with metastatic colorectal cancer (mCRC) and resected primary tumor. METHODS Ten thousand three hundred twenty-five patients diagnosed with mCRC between 2010 and 2015 with resected primary were identified in the Surveillance, Epidemiology and End Results (SEER) database. Overall, (OS) and cancer-specific survival (CSS) were analyzed by Cox regression with multivariable, inverse propensity weight, near far matching and propensity score adjustment. RESULTS The majority (79.4%) of patients had only liver metastases, 7.8% only lung metastases and 12.8% metastases of lung and liver. 3-year OS was 44.5 and 27.5% for patients with and without metastasectomy (HR = 0.62, 95% CI: 0.58-0.65, P < 0.001). Metastasectomy uniformly improved CSS in patients with liver metastases (HR = 0.72, 95% CI: 0.67-0.77, P < 0.001) but not in patients with lung metastases (HR = 0.84, 95% CI: 0.62-1.12, P = 0.232) and combined liver and lung metastases (HR = 0.89, 95% CI: 0.75-1.06, P = 0.196) in multivariable analysis. Adjustment by inverse propensity weight, near far matching and propensity score and analysis of OS yielded similar results. CONCLUSIONS This is the first SEER analysis assessing the impact of metastasectomy in mCRC patients with removed primary tumor on survival. The analysis provides compelling evidence of a statistically significant and clinically relevant increase in OS and CSS for liver resection but not for metastasectomy of lung or both sites.

中文翻译：

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基于人群的SEER分析在有或没有切除肺和肝转移的大肠癌患者中的生存情况。

背景技术在所有CRC患者中大约三分之一出现或随后发展为结肠直肠肝转移（CRLM）。这项基于人群的分析的目的是评估仅转移性结直肠癌（mCRC）和切除的原发性肿瘤患者，仅切除肝脏，仅切除肺以及肝和肺转移对生存的影响。方法在“监测，流行病学和最终结果（SEER）”数据库中，确定2010年至2015年间有132例被诊断为mCRC且原发灶切除的患者。总体而言，通过多变量，逆倾向权重，近距匹配和倾向评分调整的Cox回归分析（OS）和癌症特异性生存率（CSS）。结果大多数患者（79.4％）仅发生肝转移，仅7.8％发生肺转移和12。肺和肝转移率为8％。有无转移灶的患者3年OS分别为44.5和27.5％（HR = 0.62，95％CI：0.58-0.65，P <0.001）。有肝转移的患者（HR = 0.72，95％CI：0.67-0.77，P <0.001）转移切除术可统一改善CSS，但有肺转移的患者（HR = 0.84，95％CI：0.62-1.12，P = 0.232）没有改善多变量分析显示，合并肝和肺转移灶（HR = 0.89，95％CI：0.75-1.06，P = 0.196）。通过逆倾向权重，近距匹配和倾向得分进行的调整以及对OS的分析得出了相似的结果。结论这是第一个SEER分析，用于评估转移性切除术在已切除原发肿瘤的mCRC患者中对生存的影响。