Brain metastases from colorectal cancer: main clinical factors conditioning outcome

The aim of our study is to evaluate the outcome of patients affected by brain metastases from colorectal cancer and to correlate the outcome with prognostic factors.

Patients were retrospectively evaluated. Survival distributions were estimated by using the Kaplan-Meier method. The log-rank test was used to assess the impact on survival of individual factors.

Among 41 patients (25M and 16F; median age 58), 58.5 % had rectal cancer and 39 % synchronous metastatic disease; 95 % had extracranial metastases, most common site was lung (87.8 %). Seven patients had synchronous brain metastases. Median overall survival after diagnosis of brain metastases was 5 months [95 % confidence interval 3-12 months]. Median survival from brain metastases diagnosis was 4.2 months in patients treated with radiotherapy (29.3 %), 11.9 months in those with radio- and chemotherapy (21.9 %) and 21.4 months in those with surgery with/without radiotherapy or chemotherapy (29.3 %) (P < 0.0001). On multivariate analysis, no independent prognostic factors were found for disease-free interval from diagnosis to brain metastases and overall survival; amount of chemotherapy before brain metastases have no statistically significant relation to brain-metastases-free-interval even if patients who received more than one line of chemotherapy have a longer median brain-metastases-free-interval than those who received less than one. KRAS was found mutated in 17/28 patients without statistically significant correlation to outcome due to the small sample size.

Prognosis of brain-metastases-patients is poor. An interesting tool is to evaluate the correlation of KRAS status and brain metastases with aim to tailor treatment and follow-up.