NEW YORK (GenomeWeb) – HER3 expression levels can distinguish colorectal cancer patients with wild-type RAS tumors who will respond to anti-EGFR therapy, according to a new study.
While RAS testing can identify colorectal cancer patients who won’t respond to treatment with an anti-EGFR therapy like panitumumab, it doesn’t necessarily identify patients who will benefit from such treatment.
Using samples and data from the PICCOLO trial, researchers from the US and the UK examined whether levels of HER3 mRNA could predict which patients would do well on the topoisomerase inhibitor irinotecan in combination with panitumumab, as compared to irinotecan alone. As they reported in JAMA Oncology today, the researchers found colorectal cancer patients with high HER3 mRNA levels benefited from the addition of panitumumab, while those with low levels did not.
“HER3 appears to be a helpful test — in about half the patients who might otherwise receive panitumumab, it shows that the drug would be ineffective or even harmful, and these patients could instead be offered another treatment option,” first author Jenny Seligmann, from the University of Leeds, said in a statement.
The randomized, multi-center PICCOLO trial sought to determine whether adding panitumumab to irinotecan treatment would help patients with