Journal Club: NHS-Galleri (GRAIL)
NHS-Galleri is the largest randomized controlled trial ever conducted for an MCED test. It was launched in England in 2021 and enrolled 142,924 adults aged 50 to 79 with no symptoms or suspicion of cancer.
Read moreLatest Posts - From Newest to Oldest
The Competitive Landscape
In the two years since GRAIL's Galleri became commercially available in the US, a second MCED test was launched commercially at a lower price point (Exact Sciences’ Cancerguard), a third company obtained FDA Breakthrough Device Designation for its own MCED test (Guardant’s Shield MCD), Medicare…
Read moreRegulation and Reimbursement
In the US, a clinical laboratory test can reach patients through one of two main pathways.
Read moreThe Case Against the Blood Test
If you've been reading this book, you know that I believe MCED testing has a trajectory that points toward a future where MCED testing may be integrated into preventive care, like mammograms and colonoscopies are.
Read moreJournal Club: Shield MCD (Guardant)
In April 2025, Guardant presented clinical validation data for its MCED test (Shield MCD) at AACR. The presentation evaluated samples from 778 participants in a blinded case-control design (similar to CCGA and DETECT-A). Of these 778 participants, 375 had a known cancer diagnosis, while 403 did not have cancer.
Read moreJournal Club: DETECT-A and Cancerguard (Exact Sciences)
The CancerSEEK test, the MCED test used in DETECT-A, was an early version of what became Cancerguard. The CancerSEEK concept was first described in a landmark 2018 paper published in Science. That study was a case-control analysis of 1,005 patients with known, nonmetastatic cancers of eight types…
Read moreJournal Club: PATHFINDER 2 (GRAIL)
PATHFINDER 2 was a prospective, multi-center, interventional study conducted at healthcare institutions across the US and Canada, spanning academic centers like Mayo Clinic, Duke, Oregon Health & Science University, and Weill Cornell, alongside community sites like Ochsner Health, Henry Ford, and Hoag Memorial.
Read moreJournal Club: PATHFINDER (GRAIL)
PATHFINDER was a prospective cohort study conducted at seven US health networks, including both oncology and primary care outpatient clinics. Between December 2019 and December 2020, the investigators enrolled a "convenience sample" (a non-probabilistic sampling method where participants are chosen…
Read moreJournal Club: CCGA (GRAIL)
The Circulating Cell-free Genome Atlas (CCGA) was a large, prospective, case-control, observational study that enrolled 15,254 participants across 142 sites in North America between August 2016 and February 2019. 8,584 participants had a recent cancer diagnosis, and 6,670 did not.
Read moreStatistical Terms
In the posts ahead, I will delve into clinical studies. Those posts are full of statistical terms like sensitivity, specificity, positive predictive value, and more. I encourage you to bookmark this post, as I'll reference the terms in it frequently.
Read moreHow MCED Testing Works
I'm going to start with a primer on biology. If you already have a working knowledge of DNA, gene expression, and epigenetics, skip ahead to "More about Methylation" below.
Read moreWhy I'm Doing This
My name is Michael LaPelusa and I'm a hematologist and medical oncologist. I graduated from hematology and medical oncology fellowship at MD Anderson Cancer Center in 2026. This post is about why I wrote this book.
Read more