Wading deeper into liquid biopsy
March 2019—The standard riff for talking about a promising new cancer test should be familiar to anyone within sneezing distance of a laboratory: There’s no one-size-fits-all assay. But if any test were to come close, it would be liquid biopsy. Are clinicians eager to use it? Check. Is it relatively simple to do (check) with fairly quick turnaround times (check)? Does it work for solid and hematological tumors? Check and check. Across multiple specimen types—serum, urine, vitreous fluid, cerebrospinal fluid, stool? Quite likely. Can it be used to characterize patients’ molecular profiles, monitor therapy, assess tumor evolution, identify resistance mechanisms, and detect early disease and minimal/measurable residual disease? Half a dozen checks. Even if liquid biopsy does fall short of a one-size-fits-all assay, it’s doing a reasonable impression of a Swiss Army knife (if not Sergeant Troy’s sword fantastic, for those of you who are Thomas Hardy fans).