BACKGROUND Approximately 38% of patients with colorectal cancer will develop isolated liver metastases. Sidedness of colon tumor is identified in non-metastatic and unresected metastatic cancers as predictive of survival, yet its dedicated analysis in resected liver metastases is minimal. Our primary aim was to assess whether left-sided primary tumors improve prognosis in stage IV cancer patients undergoing curative-intent liver metastasectomy; it was hypothesized that it would. METHODS This is a retrospective, observational cohort study from 1996 to 2016 in a single tertiary-care facility. Survival from diagnosis was calculated via Kaplan-Meier method and compared between the right and left sides via log-rank analysis. RESULTS Median survival differs significantly between colorectal tumors of the right and left origins after hepatic metastasectomy in 612 patients. In patients with right-sided tumors, median survival from diagnosis was 4.5 years (IQR 4.1-5.3), and 6.3 years (IQR 5.6-6.9) in those with left tumors (HR 1.5, 95% CI 1.38-1.60, p < 0.001). CONCLUSION As in studies on earlier-stage or unresected metastatic disease, tumor sidedness is an important prognostic factor in patient survival with liver metastasectomy. Clinical risk scores should include side of primary tumor. Further work is needed to determine the molecular basis for this difference.

中文翻译：

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原发肿瘤单侧性对因转移性结直肠癌接受肝切除术的患者的预后意义。

背景大约38%的结直肠癌患者会出现孤立性肝转移。在非转移性和未切除的转移性癌症中，结肠肿瘤的单侧性被认为是生存的预测，但其对切除的肝转移的专门分析却很少。我们的主要目的是评估左侧原发肿瘤是否可以改善接受治疗性肝转移瘤切除术的 IV 期癌症患者的预后；据推测会的。方法 这是一项 1996 年至 2016 年在单一三级医疗机构进行的回顾性、观察性队列研究。通过 Kaplan-Meier 方法计算诊断后的生存率，并通过对数秩分析比较右侧和左侧。结果 612 名患者接受肝转移切除术后，左右起源的结直肠肿瘤的中位生存期存在显着差异。右侧肿瘤患者的中位生存期为 4.5 年 (IQR 4.1-5.3)，左侧肿瘤患者的中位生存期为 6.3 年 (IQR 5.6-6.9)（HR 1.5，95% CI 1.38-1.60，p < 0.001） ）。结论 与早期或未切除转移性疾病的研究一样，肿瘤单侧性是肝转移切除术后患者生存的重要预后因素。临床风险评分应包括原发肿瘤的一侧。需要进一步的工作来确定这种差异的分子基础。