Good chat with a liver surgeon today who favours using SIRT to...

Good chat with a liver surgeon today who favours using SIRT to downstage tumours. Good prolonged local control, as evident from the SIRFLOX data, and preserves liver function which is the major cause of death from metastatic colorectal cancer. These patients will have micrometastatic disease, you can detect circulating tumour cells in the blood, treating the liver tumour with SIRT buys time to treat the systemic disease.

We know that SIRT confers a survival benefit in the salvage setting for liver mets with chemorefractory disease. That is in cases where the systemic disease is progressing despite multiple lines of chemotherapy.

In the SIRFLOX trial we are looking at first line chemotherapy, i.e. there are still other options if and when the patients progress. We saw progression in both cohorts because the micrometastatic disease eventually becomes resistant to chemotherapy. I presume that it would be free for the investigators at sites involved to initiate 2nd and 3rd line regimens as they see fit once 1st line failed. Might even be allowed to cross over (e.g. SIRT in late line). Unlike the salvage setting there are still options to control the progressing disease.

If you annihilate the main liver tumour so well with SIRT, and you can treat the systemic progression, and if liver metastasis is the main cause of death, I'm having trouble seeing how there will not be a survival benefit. Just food for thought.