A Pap test combined with assays for gene mutations showed an 81% and 33% sensitivity or identifying endometrial and ovarian cancer, respectively.
In a study published in Science Translational Medicine, Yuxuan Wang, MD, of Johns Hopkins University, Baltimore, and her colleagues used a polymerase chain reaction–based test known as PapSEEK to examine Pap brush samples from 382 women with endometrial cancer, 245 women with ovarian cancer, and 714 women without cancer.
Overall, 81% of the endometrial cancer patients and 29% of the ovarian cancer patients had detectable mutations on Pap smears taken with a Pap brush. Among endometrial cancer patients, the genetic test identified mutations in 78% of patients with early-stage disease and 89% of those with late-stage disease. Among ovarian cancer patients, the genetic test identified 28% of patients with early-stage disease and 30% of those with late-stage disease.
The investigators also used the genetic test on Tao brush samples from the intrauterine cavity from a subset of 123 patients with endometrial cancer, 51 with ovarian cancer, and 125 controls and identified genetic mutations in 93% and 45% of endometrial and ovarian cancers, respectively.
The results demonstrate the potential of mutation-based diagnostic testing, and samples taken with the Tao brush may be especially helpful for ovarian cancers, especially in samples combining Pap and plasma sample data, the researchers said.
The study was limited by several factors including its retrospective design and having a study population confined to women with known cancers, the researchers noted. More research is needed, but results suggest the potential for DNA analysis to catch cancers early in a screening setting, they said. “Our study lays the foundation for evaluating PapSEEK in a large prospective study,” ideally including patients at high risk for gynecologic cancers, they added.
The study was funded by multiple sources including the Virginia and D.K. Ludwig Fund for Cancer Research, the National Institutes of Health, and the Stand Up to Cancer Colorectal Dream Team Translational Research Grant. Dr. Wang and several coauthors disclosed patent, equity, and royalty interest in technologies discussed in the paper. Four coauthors are cofounders of and stockholders in PapGene, which has licensed technologies related to the work described in the paper.
SOURCE: Wang Y et al. Sci Transl Med. 2018 Mar 21;10(433):eaap8793.