Phase III Diagnostic Trial for Early Detection of Endometrial/Ovarian Cancer and Hereditary Predisposition of These Cancers

Early stage high-grade cancer, endometrial and ovarian, has few, if any, symptoms or signs. When symptoms appear, the disease is commonly in advanced stage meaning it has left the gynaecological organs and metastasized to the pelvic/abdominal cavity. The McGill research group had showed in the DOvEE trial (NCT02296307), that fast-track assessment with transvaginal ultrasound scans (TVUS) and serial CA125 of women with vague symptoms associated with ovarian and endometrial cancer did diagnose these cancers earlier in the disease trajectory, with low-volume resectable disease, but only after the cancer had already become Stage III. One way to detect these cancers earlier is to screen asymptomatic women. Unfortunately, none of the currently available tests, including TVUS and CA-125 have been shown to be useful for screening for ovarian or endometrial cancer.

The McGill team has developed a genomic assay to screen and detect these cancers earlier in the trajectory than is currently the case. The test identifies pathogenic somatic mutations (necessary early steps in the development of these cancers), in an uterine cytological sample. It is able to do so by incorporating a machine-learning derived classifier that can discriminate the mutational signature of these cancers from benign disease with a sensitivity of 80% and a specificity of 100% in a healthy population of peri- and post-menopausal women. In addition to the uterine sample, the test includes a saliva sample that acts as an internal control but can also identify germline pathogenic variants that predispose to hereditary endometrial/ovarian cancers as well as breast, pancreas, and colon cancers.

The test was developed in a retrospective population in whom the assay was done pre-operatively and the diagnosis of malignancy versus benign gynecological disease was confirmed by detailed pathological analysis of the uterus, tubes, and ovaries after surgical resection (NCT02288676). The test is now ready to be tested as a phase III diagnostic test in the general population to see if these results are just as promising in the community at large.