Risk factors for brain metastases in patients with metastatic colorectal cancer

Abstract

The incidence of BM was 8.8% in patients with mCRC who received third-line therapy. The most important risk factor for developing BM was lung metastases. Furthermore, rectal cancer, metachronous metastatic disease and long survival were linked to BM development.

Associations between primary tumor RAS, BRAF and PIK3CA mutation status and metastatic site in patients with chemo-resistant metastatic colorectal cancer

“…In that study, we identified 42 patients with brain metastases, of whom six developed brain metastases before start of CetIri treatment and 36 developed it later. We were not able to identify any significant association between the development of brain metastases and mutations in KRAS, NRAS, BRAF or PIK3CA genes [3]. In other studies, PIK3CA and RAS mutations (especially KRAS exon 2 mutations) have been connected with an increased risk of brain metastases [9,11,14].…”

“…In 73 patients, KRAS exon 2 and BRAF mutations had previously been identified using TheraScreen V R KRAS mutation kit and pyrosequencing, and no new mutation analysis was performed. This has been described previously [3].…”

“…All patients in the database with available mutation status were included in this study to examine the association between mutations in RAS (KRAS and NRAS combined), BRAF V600E and PIK3CA (Supplementary Table 1 shows mutations defined as relevant for each gene) and the likelihood of having metastases at different metastatic sites (liver, lung, peritoneum, bone, ovary and skin). In a previous study, we investigated the association between brain metastases and the different mutations in this cohort, and brain metastases were not included in this study [3]. As part of this study, the database was reviewed for errors in data registration regarding dates and sites registered.…”

“…All patients receiving CetIri between 1 January 2005 and August 1st 2008 at the oncology wards of three Danish hospitals (Herlev, Odense and Aalborg Hospital) were registered. Patients with other active primary tumors, and patients whose tissue samples or medical charts were not available were excluded [3].…”

“…The pattern of metastases varies significantly between colon and rectal cancer. Rectal cancers more often seed lung, bone and brain and less often peritoneum compared to colon cancers [3,4]. Furthermore and regardless of primary tumor, patients with lung metastases more often have nervous system and bone metastases whereas they rarely have peritoneal metastases [4].…”