Blood tests can be useful to detect cancer. But they have limitations: they may only be useful for a single cancer or require tumor tissue. The Menlo Park-based company GRAIL has developed a tissue-free, multi-cancer detection test (“Post-Diagnosis Cancer Research Solution”) based on methylation sequencing of cfDNA from blood. The test can currently be used to evaluate cfDNA applications in cancer research, including, they say, “treatment evaluation, recurrence monitoring, and prognostic guidance.”
During a late-breaking poster session on the last day of the AACR meeting, the company presented analytical validation data on this recently launched test which leverages the proprietary methylation platform to evaluate cfDNA isolated from blood. GRAIL had announced the availability of this research use only (RUO) test for biopharmaceutical companies just a few months ago—in January.
The study analyzed cfDNA blood samples from cancer and non-cancer donors. Analytical sensitivity was assessed in 12 different solid tumor types. Results demonstrated a median limit of detection (LOD95) of 0.023% based on measures of the abnormally methylated ctDNA fraction. Analytical specificity was 98.47% and overall precision across replicates was 94.6%.
“These results are an important step in establishing the performance of our post-diagnostic methylation-based solution for cancer research,” said Jeffrey Venstrom, MD, chief medical officer at GRAIL. “Current post-diagnostic cancer detection tests often require tumor tissue and are limited by their specificity to a narrow set of cancers. With GRAIL’s methylation technology, the analytical study results showed that we can detect multiple types of cancer with strong sensitivity without the need for a tissue sample. This solution is a versatile option for a range of research uses including cancer prognosis, identification of minimal residual disease and recurrence monitoring, and biomarker discovery.”