Genetic test for cancer is less accurate for Black and Asian peopleA study of genetic test results used to guide cancer treatment found that Black people had their tumours misclassified twice as often as white peopleGenetic tests that predict the efficacy of certain cancer treatments aren’t as effective for people of African or Asian ancestry.Drugs called immune checkpoint inhibitors, which work by turning the immune system against tumours, have been shown to be quite effective against cancers in people with high TMB, but less so in people with fewer mutations.“If we’re misclassifying more Blacks and Asians as having high TMB, then we’re more likely to give them [immune checkpoint inhibitors],” says Nassar.What’s more, even accurate TMB scores may not be as useful for guiding treatment decisions for people who are Black or Asian.They found that, after 36 months on checkpoint inhibitors, the overall survival rate for people of European ancestry with high TMB was 42 per cent compared with 22 per cent in those with low TMB."