在患有结直肠癌和同步肝转移的患者中，与肝转移相关的疾病负担是导致寿命缩短，最终死亡风险的主要原因。手术切除是治疗结直肠癌肝转移的潜在可治疗方法。在同步治疗情况下，如果肝转移和原发肿瘤都可以切除，且风险相对较低，肿瘤外科医生和患者可以考虑三种潜在的治疗策略。首先，采用“分期”或“同时”手术方法。其次，针对分期策略，“传统方法”会建议先切除原发肿瘤（结肠癌或直肠癌），康复后进行肝部手术。优先进行肝脏切除手术的是“先切肝脏再切原发肿瘤”策略。规划一项手术试验，调查两种器官的肿瘤切除术，其切除程度和复杂性高度不确定，以及围手术期化疗（放疗）的潜在影响，使得难以找到最理想的主要终点。因此，我们建议进行调查试验，采用精心选择的组合终点以及嵌入的风险分层策略，以识别那些可能从同时手术中获益的患者亚组。

In patients presenting with colorectal cancer and synchronous liver metastases, the disease burden related to the liver metastasis is the driving cause of limited longevity and, eventually, risk of death. Surgical resection is the potentially curative treatment for colorectal cancer liver metastases. In the synchronous setting where both the liver metastases and the primary tumor are resectable with a relative low risk, the oncological surgeon and the patient may consider three potential treatment strategies. Firstly, a "staged" or a "simultaneous" surgical approach. Secondly, for a staged strategy, a 'conventional approach' will suggest removal of the primary tumor first (either colon or rectal cancer) and plan for liver surgery after recovery from the first operation. A "Liver first" strategy is prioritizing the liver resection before resection of the primary tumor. Planning a surgical trial investigating a two-organ oncological resection with highly variable extent and complexity of resection as well as the potential impact of perioperative chemo(radio)therapy makes it difficult to find the optimal primary endpoint. Here, we suggest running investigational trials with carefully chosen composite endpoints as well as embedded risk-stratification strategies to identify subgroups of patients who may benefit from simultaneous surgery.