March 21, 2018, New York — A Ludwig Cancer Research study reports the analysis of an experimental, minimally invasive DNA test for the detection of ovarian and endometrial cancers, both of which are difficult to detect in their early stages, when they are most curable.
Named PapSEEK, the test is being developed by researchers at Ludwig Johns Hopkins and their colleagues at the Johns Hopkins Kimmel Cancer Center to detect DNA mutations and chromosomal aberrations in cells shed by ovarian and endometrial tumors with the aim of catching the malignancies earlier. Earlier detection can significantly improve outcomes for patients.
The PapSEEK study, led in part by Ludwig Johns Hopkins researcher Nickolas Papadopoulos, appears in the March 21 issue of Science Translational Medicine. Co-directors of the Ludwig Center at Johns Hopkins Bert Vogelstein and Kenneth Kinzler contributed to the study as well.
PapSEEK examines cervical fluid samples to detect aneuploidy—abnormal numbers of chromosomes in cells—or mutations in 18 genes that are commonly disrupted in endometrial or ovarian cancers. The researchers analyzed 1,958 samples obtained from 1,658 women, including 658 endometrial or ovarian cancer patients and 1,002 healthy controls. PapSEEK was nearly 99% specific for cancer, and detected 81% of endometrial cancers (78% of which were early-stage cancers) and 33% of ovarian cancer cases (34% were in early stages).
Obtaining cervical fluid samples using a Tao brush, which extends further into the cervical canal and collects cells closer to where the cancers tend to originate, improved the sensitivity of the test. In the 123 endometrial cancer patients studied using Tao brush samples, PapSEEK identified cancer 93% of the time. In the 51 ovarian cancer patients studied, 45% tested positive with PapSEEK. There were no false-positive results. When the plasma and Pap brush samples were both tested, the sensitivity of the test for ovarian cancer increased to 63%.
The cancer prevention initiative launched by the Ludwig Institute for Cancer Research and the Conrad N. Hilton Foundation helped support both studies.
The media release from which this summary is derived can be found here.