Brain metastases from colorectal cancer: main clinical factors conditioning outcome.

Background: 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.

Methods: 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.

Results: 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.

Conclusions: 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.