Brain metastasis from colorectal cancer: clinical characteristics, timing, survival and prognostic factors

Background: Brain metastasis (BM) from colorectal cancer (CRC) seriously affects the survival and quality of life of patients. However, this disease is not fully understood. It is not clear when follow-up monitoring should be conducted to achieve early diagnosis. Furthermore, the reported prognostic factors have varied among different studies. Our study aims to determine the clinicopathological, survival and prognostic factors, as well as the timing of BM occurrence.Methods: We retrospectively studied the patients with BM from CRC between January 2000 and July 2017. The clinicopathologic features were assessed, and the time from primary tumor surgery and extracranial metastases (lung, liver and bone) to the occurrence of BM was calculated, respectively. Survival time after BM was statistically analyzed. Multivariate Cox analysis was carried out to determine the independent factors that affected survival.Results: 52 patients were analyzed. Most of the patients (86.5%) had combined extracranial metastases when BM was diagnosed, and lung was the commonest extracranial metastasis location. The median time interval from CRC surgery to the diagnosis of BM was 20.5 months, and the median time interval from lung, liver and bone metastases to BM was 7, 5 and 2 months, respectively. After diagnosis of BM, the median survival was 9 months. Extracranial metastases (p =.012) and Karnofsky performance status (p =.025) were independent prognostic factors based on multivariate analysis.Conclusion: BM from colorectal cancer often occur in the late stage, and has an extremely poor prognosis. Identifying the timing of brain metastasis can help to detect this disease early.