[Prognostic factors of patients with unresectable liver metastasis from colorectal cancer after failed conversion chemotherapy].

OBJECTIVE: To explore the prognostic factors of patients with unresectable liver metastasis colorectal cancer after failed conversion chemotherapy.

METHODS: A retrospective, case-controlled study was performed. Study subjects were 105 patients who were diagnosed with synchronous liver metastasis colorectal cancer after failed chemotherapy (metastasis evaluated as unresectable after the conversion chemotherapy) at Xinhua Hospital, Shanghai Jiaotong University from January 2012 to December 2015. Overall survival(OS) was retrospectively analyzed using Kaplan-Meier method. Log-rank test was used to compare survival among groups. Univariate and multivariate analysis was conducted for prognosis using Cox regression model.

RESULTS: Of 105 cases,70 were male and 35 were female with median age of 60 years old. Twenty-one patients had right colon cancer, 41 had left colon cancer, 42 had rectal cancer and 1 had synchronous cancers(sigmoid colon and rectum). One hundred and two (97.1%) patients were cT3-4 and 90 patients were cN+ (imaging diagnosis). Eighty-nine (84.8%) patients were loaded with 2 or more liver metastases with the median maximum diameter of 48.3 mm. The patients were followed up for 3 to 43 months from the day of diagnosis. The median OS was 11 months (interquartile range, 8-18). The median OS of patients with cN0, cN1 and cN2 stage was 17, 13 and 10 months, respectively(P=0.026). The median OS of patients with single lesion, 2-3 lesions, 4-10 lesions and more than 10 lesions was 15, 15, 17 and 9 months, respectively (P=0.002). OS of patients with maximum diameter of liver metastatic lesion ≤ 50 mm, 51-100 mm and >100 mm was 15, 10 and 8 months, respectively(P=0.003). The median OS of patients with chemotherapy response of partial response (PR), stable disease (SD) and progressive disease (PD) was 17, 14 and 8 months, respectively(P<0.001). OS was 17 months in patients receiving second line chemotherapy and was 10 months in those without second line chemotherapy (P<0.001). OS in patients undergoing primary tumor resection was 13 month and in those without primary tumor resection was 9 months; the difference was not significant (P=0.060). Multivariate analysis showed that cN2(HR=2.115, 95%CI:1.089-4.109, P=0.027), the maximum diameter of liver metastatic lesion more than 100 mm (HR=3.112, 95%CI:1.455-6.657, P=0.003), chemotherapy response of PD (HR=4.435, 95%CI:2.506-7.533,P<0.001) and without second line chemotherapy(HR=4.432,95%CI:2.186-8.986, P=0.010) were independent prognostic factors.

CONCLUSIONS: For patients with unresectable liver metastasis from colorectal cancer after failed conversion chemotherapy, prognostic factors include cN2, the maximum diameter of liver metastatic lesion, chemotherapy response and second line chemotherapy. Whether the resection of primary tumor can prolong OS further study.