ESH CLL 2022 | The importance of genomic testing in CLL prognosis

Well, genomic testing isn’t used in diagnosing patients with CLL. The diagnosis of CLL is still based on morphology and flow cytometry cell surface markers. Where genomic testing comes in is in terms of prognostic testing. So once you’ve identified a clone, that is a monoclonal B-cell population consistent with the diagnosis of CLL, you then want to look at the DNA to try to understand what mutations are driving the development of that cancer. That’s important, not only for helping us to understand the biology of the disease, how aggressive or indolent it will be, but most importantly now for helping to select appropriate therapies for patients. For example, a patient who has NextGen sequencing and has identified a p53 mutation should not be receiving chemo-immunotherapy under any circumstances. I think there’s a debate happening right now, whether those patients should be receiving a continuous therapy, for example, a BTK inhibitor or a time-limited approach and what would be more appropriate.

And so the genomic testing is not only important for prognosis, but for selecting first therapy, for example. And then the next area where it will be relevant is identifying mechanisms of resistance to currently approved targeted therapies. And once we know that piece of the puzzle, then it’ll be useful for selecting next therapies. For example, a patient who has a BTK mutation versus a PLC gamma 2 mutation might have different implications for selecting next therapy, following a covalent BTK inhibitor, for example. So very, very close or much closer these days to a personalized approach for patients. And certainly the genomic testing is really most important for helping us to get to that point.