Grail’s Multi-Cancer Early Detection Test to Bring Seismic Change to Oncology Diagnosis and Treatment

Recently, I attended a Grail management presentation about the company’s Multi-Cancer Early Detection (MCED) blood test and found its potential impact on healthcare astounding. The Galleri blood test detects fifty types of cancer using loose particles of DNA circulating in the blood stream. Looking at methylation patterns on these DNA pieces, it can determine if the patient has cancer and in what organ it is located. This is exciting news, because it can help detect cancers earlier, before they have metastasized to other organs such as the liver, lungs, and brain.

The clinical impact could be huge as the prognosis for the patient improves with earlier cancer tumor detection. I know early detection matters as the thesis for my investment in breast imaging company U-Systems was that ultrasound would detect more cancers earlier in women with dense breasts. While the overall breast cancer survival rate is 90%, with earlier detection five-year survival was 99%. And conversely five-year survival of stage 3 cancer that involves the lymph nodes is 87%. And sadly, for patients with stage  4 (metastatic) breast cancer that statistic drops to 28%. Early detection is lifesaving.

The Kaplan Meier survival curves below illustrate another example of the benefits of early detection in lung cancer.

Once a cancer becomes metastatic there are two problems, the first is treating the location where the metastasis has found a new home. And the second can be finding the original cancer to treat the problem at its source. Locating that source can be exceedingly difficult. In my venture capital days, I came close to investing in a company that could take a slice of a metastatic tumor and identify the tissue of origin (TOE). It worked, but not well enough to become the standard of care.

The Galleri MCED test identifies fifty types of cancers. Interestingly 80% of cancers do not have a screening test. Thus, even if one regularly gets a mammogram, a pap smear, a colonoscopy, and a lung CT, the test adds value by providing additional broad screening coverage. A blood test is easy to administer as my physical routinely involves a blood draw, so taking another tube adds only ten seconds.

Galleri is available in the US today and I have spoken to extremely health-conscious people who have used the test on a cash pay basis. They view it favorably. On my next physical I will follow their lead.

Incorporating the test in our healthcare system will take time. Broad availability and reimbursement will happen after the company completes clinical trials and works through the payer system. As always, there will be hiccups and challenging discussions around sensitivity, specificity, and predictive value. There is a trade off between sensitivity and specificity as identifying more cancers (sensitivity) can result in more false positives (or lower specificity.)  The statisticians will have fun debating these values and the relative merits in different cancer types. The published sensitivity is 69% for twelve cancers that make up two-thirds of cancer mortality. That is good, but not phenomenal. On the other hand, the specificity is 0.5% meaning that it sends very few people for unnecessary follow up. Conversely Mammograms generate further work on 10% of screened patients at significant cost with only 1 in 20 of those patients having cancer.

The test’s exact effects on our healthcare system are difficult to predict but it is interesting to ponder the impact on our healthcare system and its incumbents.

Who wins?

Patients- Galleri will save lives through earlier cancer detection and in a sizable portion of cases, treatments will be less onerous and less costly.

Imaging companies- Patients who learn they have tumors will need imaging to locate it, necessitating detailed CT or MRI imaging. Since the cancers are small, it will continue the drive to better resolution and AI enhancement.

Tumor characterization companies- More treatable cancers means more treatment plans and clinical decision points. What pharmaceutical agent will work best? Would post surgical radiation be helpful? Is the tumor likely to recur?

Hospitals- The number of procedures to remove these small tumors should rise.

Insurers- The same number of people will be getting cancer, but they will be diagnosed earlier when it should be less costly to treat.

The medtech industry- Older people require more medical technology. For example, the use of artificial joints is age related. By growing the older population through lower cancer mortality, the customer population grows.

Who loses?

Existing screening technologies- It is unusual for a medical device to become obsolete, but the existing screening businesses may shrink  and/or need to change. Surely more fastidious patients will want to stop collecting their stools for mailing and opt for a blood test. It is possible that certain low-risk patients might be channeled into lower frequency protocols with Galleri as an adjunct.

Radiation Therapy equipment- This business could go either way. On the one hand, more treatable cancers identified could lead to more radiation therapy regimens. But on the other hand, these are smaller more localized cancers that may not need the heavy artillery of radiation therapy.

With the Galleri MCED test, our healthcare system is on the cusp of enormous change that will advance the detection and treatment of cancer. The impact could be as significant as the introduction of antibiotics on infectious disease.