The efficacy of curative resection of distant extrahepatic metastases in colorectal cancer patients with liver metastases was examined in a study from Japan. Researchers included 377 patients who were treated for colorectal liver metastases between 2007 and 2019. Of these, 323 underwent hepatectomy; 54 patients with extrahepatic metastases underwent chemotherapy alone. Sixty patients had extrahepatic metastasis and 263 did not have extrahepatic metastasis. The median survival among  patients with extrahepatic metastasis who underwent hepatectomy was 32 months. The 3-year survival rate in this group of patients was 47%, while the 5-year survival rate was 28%. Among patients without extrahepatic metastasis, the median survival was 115 months; the 3-year survival rate was 79% and the 5-year survival rate was 66%. 

While the outcomes were comparable between patients with unresectable tumors and patients with macroscopic residual disease (R2) with EHM, patients in R0 (no residual disease) and R1 (microscopic residual disease) groups fared significantly better (p < 0.001). Patients with higher clinical risk score, partially resected extrahepatic metastasis, those who had received neoadjuvant chemotherapy earlier or in whom extrahepatic disease was identified intraoperatively had worse survival. The study concluded that surgical treatment of patients with colorectal cancer liver metastases with EHM necessitates gross curative resection. And, in patients with smaller and less lesions, resection of liver metastases should be carried out.

Hirokawa E, et al. J Gastrointest Surg. 2022 Mar;26(3):594-601.