In Hong Kong, 76 percent of nasopharyngeal cancer patients are diagnosed at an advanced stage, when treatment options can be limited. A blood test developed by Dennis Lo, a professor at the Chinese University of Hong Kong, is meant to change that. Lo said the screening could catch around 70 percent of patients early and bring the mortality rate down substantially.
Lo is known as the “Father of Non-Invasive Prenatal Testing.” Since 1997 he has searched for fetal DNA in the blood of pregnant women. His work led to a noninvasive test for Down syndrome, a condition that before then could be detected only with techniques that could put the fetus at risk. The test launched in 2011. Millions of these tests are now run each year around the world.
From pregnancy to cancer
The technique analyzes cell-free DNA in blood plasma, and it goes by the name liquid biopsy. His team first used it for prenatal testing, then adapted it for other work: genetic disorders such as thalassaemia and Duchenne muscular dystrophy, bacterial infections, organ transplant rejection and about a dozen types of cancer.
Lo said it took him three years to work out how to tell fetal DNA from the mother’s in plasma. The answer came from a statistical theory. He credits colleagues Rossa Chiu and Allen Chan with turning many of his ideas into working tests.
“There is an exchange of genetic information between baby and mother,” he told El Pais in 2024.
Screening results
Nasopharyngeal cancer is common in southern China. Lo said a Cantonese man has a lifetime risk of 1 in 39. Without screening, around 75 percent of cases are found at stage three or four. With screening, 70 percent are found at stage one or two, and survival improves about tenfold. His team published the result in the New England Journal of Medicine in 2017, and the test is now being rolled out in Hong Kong.
Screening for many cancers at once is harder, because each tumor has its own mutations. Lo’s group built a test that reads epigenetic changes, which differ from organ to organ and show where a cancer sits. It was licensed to Grail, where Lo was a scientific co-founder. Grail’s test covers 50 types of cancer. By the company’s latest published data, a positive result means a 75 percent chance of cancer, a negative one 2.5 percent, and the test locates the cancer with 86 percent accuracy. Lo called the weak spot plain: sensitivity is about 25 percent at stage one and 57 percent at stage two.
Business and recognition
Lo has set up several companies in the past decade, and three were acquired or received capital from listed companies. His laboratory holds nearly 1,500 patents in different jurisdictions. He plans a new company in the Greater Bay Area, population over 80 million, focused on nasopharyngeal cancer.
His awards include the King Faisal International Prize for Medicine in 2014, the AACC Wallace H. Coulter Lectureship Award in 2015 and the Future Science Prize in life science in 2016. In 2024 he traveled to Madrid to receive the Conchita Rabago de Jimenez Diaz Foundation’s memorial lecture award.
Sources
- Unlocking the body’s secrets with a drop of blood | CUHK Communications and Public Relations Office
- Dennis Lo, molecular biologist: ‘There is an exchange of genetic information between the baby and the mother’
