The Oracle of Delfi: Finding Every Cancer Early

DFJ Growth
DFJ Growth News
Published in
4 min readJul 18, 2022


By Justin Kao, Jocelyn Kinsey, and Delaney Ugelstad

We are excited to announce DFJ Growth’s investment in Delfi Diagnostics, where we’ve led the company’s $225 million Series B financing. Delfi is the emerging leader in low-cost, non-invasive early cancer detection. The company’s technology promises to enable routine cancer screening through a simple blood test, accelerating cancer detection by months or years.

Cancer is the second leading cause of death globally, but when diagnosed early, survival rates increase more than fourfold. As they grow and mutate, cancer cells shed tiny quantities of molecules into the blood. Identifying these warning flags early requires finding the proverbial “needle in a haystack” — reading the volumes of biological data in your blood, and then detecting a faint signal amongst all the noise.

Over the past two decades, scientific and technical advances have begun to meet this challenge. First, plummeting sequencing costs have unlocked mass amounts of biological data, with the promise of transforming the way we detect and treat many types of diseases. Second, modern data science approaches can sift through these mountains of data better than ever before.

This convergence of genomic science with compute power and data analytics — a trend that we call “Unlocking the Genome” at DFJ Growth — has catalyzed a race to accurately detect cancer via simple blood tests.

This form of testing, often referred to broadly as “liquid biopsy,” is both more accessible than current modalities and more powerful as many types of cancer can be detected simultaneously.

At DFJ Growth, we have been closely monitoring the developing liquid biopsy field for the last decade, searching for a company poised to realize the full vision of mass-market, non-invasive cancer screening. For an annual cancer screen to be accessible to every person in the world, we need an easy-to-perform blood test that is both accurate and affordable.

We believe we have finally found this in Delfi’s proprietary technology, which has the potential to detect multiple types of early-stage cancer from a single blood test. The company’s elegant assay is the first we have seen that is sufficiently cost-effective to support early cancer detection at scale.

So how do they do it? Delfi detects cancer by analyzing the genome-wide profile of DNA fragments circulating in the bloodstream, a technique called “fragmentomics.” This approach works because cancer DNA breaks apart into fragment patterns that are subtly different from normal DNA. Instead of sequencing deeper or reading more types of biological data, which add cost and complexity, Delfi focuses on using computational approaches, including advanced machine learning, to tease out the nuances in fragmentomics and reliably detect cancer in its earliest stages, all at very low cost. Notably, the company can launch new products based solely on algorithm development, without changing their laboratory test, an incredibly powerful capability as it expands to multiple types of cancer.

When the Delfi team described their approach to us, our team had a light bulb moment. Their strategy mirrors our initial thesis behind our investment in Helix with its innovative “sequence once, query often” model.

Unlike today’s industry, which focuses on ever more complex laboratory assays, the diagnostics company of the future will be based on software and data science. Delfi has the potential to pioneer this model in cancer detection.

Delfi’s initial focus is on lung cancer. Lung cancer is the leading cause of cancer mortality, but also highly treatable if caught early. The current standard of care is a low-dose CT scan, which suffers from a high false positive rate and very low adoption of less than 10%. Delfi has already generated robust data on thousands of patients, received FDA breakthrough designation, and started enrolling a 15,000 patient study to support FDA approval and widespread reimbursement .

As always, we look to partner with exceptional teams. Founder and CEO Victor Velculescu is world-renowned in genomics and cancer research, and his team invented the foundational Delfi technology out of Johns Hopkins University.

Victor is complemented by an all-star team of researchers, data scientists, and clinicians who bring years of experience in cancer research and data science in both academia and industry. We are excited to complement their scientific prowess with our experience bringing disruptive technologies to market.

From SpaceX to Tesla to Commonwealth Fusion Systems, we have always sought out innovative technologies that will make a huge impact in our world. It’s hard to imagine a bigger impact than finding every cancer early and altering the course of human health. Delfi is poised to save lives around the world and catapult diagnostics into the data age. We are proud to partner with them on this important mission!