ANN ARBOR, Mich. — Scientists at the University of Michigan Health Rogel Cancer Center have developed a new at-home test capable of detecting DNA fragments released by head and neck tumors in urine samples. Researchers believe their new test may one day lead to early detection of this cancer type, which currently does not have a reliable screening method.
Human papillomavirus (HPV) is widely recognized as the cause of cervical cancer, yet it is increasingly found to also cause cancers in the mouth, throat, and additional head and neck regions. Early detection of these tumors is critical because finding cancer during an earlier stage promotes better outcomes for patients.
Through whole genome sequencing, the research team confirmed that cell-free DNA fragments released by tumor cells, which pass on from the bloodstream into urine through the kidneys, are predominantly ultra-short (fewer than 50 base pairs). Due to their small size, these fragments are much more likely to go unseen during conventional urine or blood-based liquid biopsy tests intended to detect circulating tumor DNA (ctDNA).
“In this study we provide evidence to support the hypothesis that conventional assays do not detect ultrashort fragments found in urine, since they are designed to target longer DNA fragments. Our team used an unconventional approach to develop a urine test for HPV-positive head and neck cancer ctDNA detection,” says study co-first author and research specialist Chandan Bhambhani, Ph.D., in a media release.
The research team also included Muneesh Tewari, M.D., Ph.D., professor of hematology and oncology, J. Chad Brenner, Ph.D., associate professor of otolaryngology-head and neck surgery, and Paul L. Swiecicki, M.D., associate medical director for the Oncology Clinical Trials Support Unit at Rogel.
While still currently in the discovery phase, this mail-in test has already been distributed among patients within a hundred-plus miles of Ann Arbor for research purposes. This will allow researchers to collect significant data on the efficacy of the at-home kit. After collecting a urine sample, participants ship it back to the U-M laboratory, where testing can detect the presence or absence of head and neck cancer.
“One of the most remarkable outcomes of this study is that the test that has been developed has detected cancer recurrences far earlier than would typically happen based on clinical imaging. As such, these promising results have given us the confidence to broaden the scope of the study, seeking to expanding distribution even further,” adds Prof. Brenner, co-senior author of the study.
While the focus thus far has been on head and neck cancers specifically, this project also details a new method that may help expand the test to detect other cancers as well. For instance, researchers note the test can also detect ctDNA in the urine of patients with breast cancer and acute myeloid leukemia, suggesting more opportunities remain to study the application of urine-based testing for additional cancers.
“Many people are not aware that urine carries information about many different cancer types, although it is made in the kidneys. Our findings about the difference in ctDNA fragment sizes and the test we developed for HPV-positive head and neck cancer detection provide crucial information on how urine-based diagnostic assays can be developed for different cancers,” Bhambhani concludes. “Further, these types of tests are likely to have a much higher compliance in patients requiring follow-up testing post treatment, due to the convenience of self-collection of samples, when compared to blood-based assays.”
The study is published in the journal JCI Insight.