Trial data with SIR-Spheres Microspheres in metastatic colorectal cancer shows improvement in overall survival- Sirtex

SIRFLOX and FOXFIRE Global findings with SIR-Spheres Microspheres from Sirtex suggest that adding liver-directed Selective Internal Radiation Therapy (SIRT) to standard first-line chemotherapy may improve overall survival in metastatic colorectal cancer (mCRC) patients with right-sided primary tumours, compared to those receiving chemotherapy alone. A post-hoc analysis of data from the 739-patient SIRFLOX and FOXFIRE Global studies indicates that adding SIRT with liver-directed SIR-Spheres Y-90 resin microspheres to standard first-line mFOLFOX6 chemotherapy for liver-only or liver-dominant metastatic colorectal cancer (mCRC) in patients with right-sided primary (RSP) tumours led to a statistically significant and clinically meaningful 4.9-month median overall survival benefit. This translates into a 36% reduction in the risk of death at any given time compared to patients who received chemotherapy alone.

The new data are consistent with a 2016 meta-analysis of 66 studies involving more than 1.4 million CRC patients, which found a significant prognostic impact of primary tumour site on overall survival. In particular, patients with mCRC from a left-sided primary (LSP) tumour had a 27% reduced risk of death at any given time compared to RSP patients. Patients with RSP represented more than a third (35-38%) of mCRC cases in this analysis.