Choose a side.

August 15, 2017. A unique feature of colon cancer is its frequent presentation with oligometastatic liver disease amenable to life-prolonging resection. A big question, though, is whether therapies like chemo-embolization or radiation can produce similar results in patients unfit for surgery. Selective internal radiation therapy (SIRT) is one of these approaches, which involves the delivery of tiny beads covered in radioactive material into the liver. This month Lancet Oncology published the combined results of three SIRT trials (FOXFIRE, SIRFLOX, and FOXFIRE-Global) that randomized patients to FOLFOX chemotherapy +/- SIRT. Despite good response rates (68%) and liver control (78%), SIRT did not improve overall survival. An exploratory finding was that SIRT may afford a benefit for patients with primary tumors in the ascending (right) colon. Why? There is emerging data that right-sided colon cancers behave worse than left sided tumors...and thus have more to gain from alternative therapy. So, if it adapts rather than dies, selective internal radiation may become even more selective (read: go right or go home).