Purpose: To evaluate the role of hepatic steatosis (HS) in patients with synchronous colorectal liver-limited metastases (CLLMs) undergoing conversion therapy.
Patients and methods: From March 2013 to March 2017, a total of 406 patients with initially unresectable CLLMs accepted conversion therapy in multidisciplinary team (MDT). Before the implementation of conversion therapy, all patients underwent CT scan to assess the presence of hepatic steatosis and divided into the HS group (n = 124) and the non-HS group (n = 282). After using propensity score matching (PSM) to eliminate the potential confounding bias of the two groups, the conversion hepatectomy rate and long-term oncological survival in two groups were compared.
Results: After 1:1 PSM, no significant difference was observed at baseline between patients in the HS group (n = 119) and the non-HS group (n = 119). Patients in the HS group had higher conversion hepatectomy rate from MDT evaluation (31.1% vs 18.5%, P  = 0.029) and actual hepatectomy rate (30.2% vs 18.5%, P  = 0.030), when compared with patients in the non-HS group, respectively. In addition, the HS group achieved better progression-free survival (PFS, P  = 0.047) and overall survival (OS, P  = 0.035) than that of the non-HS group. Multivariate logistic analysis confirmed that pretreatment HS was an independent predictor for conversion hepatectomy rate (OR, 2.393; 95% CI, 1.463–4.315, P  = 0.001), and multivariate Cox analysis revealed that HS was an independent prognostic factor for PFS (HR, 0.493, 95% CI 0.281–0.866, P  = 0.014) and OS (HR, 0.559, 95% CI 0.398–0.785, P  = 0.001).
Conclusion: For CLLM patients who underwent conversion therapy, hepatic steatosis could be an effective predictor for conversion hepatectomy rate and an independent prognostic factor for PFS and OS.
Keywords: colorectal cancer, liver metastases, conversion therapy, hepatic steatosis, objective response rate, survival