For liver metastases, what criteria do you use to decide between SBRT vs Y90?

The treatment of choice is ablative SBRT as long as liver constraints can be met. Kras/p53 wildtype CRC mets can be controled with 70%+ certainty at 5 years with 100Ghy BED, but Kras/p53 mut CRC mets are resistant (Hong, et al, JNCI,2017). For this reason, I use a BED of 150Gy but a dose that overcomes resistence has not been defined. Resection and thermal ablation are preferred when feasible. Ablative radiation is typically used in cases where the tumors are near the biliary tree or vessels. Y90 is logical choice for mutifocal bilobar disease. However, Y90 is generally not ablative unless it is a "segmentectomy". In my practice, I have repeatedly been asked to treat progressive CRC mets after Y90, sometimes when patients are in liver failu...