Ben Schwartz is Associate Editor, Contemporary OB/GYN.
The Food and Drug Administration (FDA) has issued an order restricting sales and distribution of the contraceptive device Essure. Plus: Can a Pap test one day be used to diagnose ovarian, endometrial cancers?
The Food and Drug Administration (FDA) has issued an order restricting sales and distribution of the contraceptive device Essure. Physicians will only be able to purchase the device after agreeing to go over a comprehensive FDA-sanctioned brochure and checklist with potential patients to ensure they are aware of the risks associated with the device.
Essure consists of two small coils made of a nickel alloy and polyester-like fiber which are inserted into the fallopian tubes through the vagina. Build-up of scar tissue around the coils creates a barrier that prevents sperm from fertilizing an egg. The device is the only permanent implantable contraceptive for women that does not require a surgical incision. Some patients who have received it have reported adverse events, including uterine and/or fallopian tube perforation, migration of inserts to the abdominal or pelvic cavity, persistent pain, and suspected allergic or hypersensitivity reactions.
In the recent announcement, the FDA noted that the restriction was based on evidence that some women were not getting adequate information about the risks of the device, despite previous efforts to educate patients and doctors. The recent action will require both physician and patient to sign a form with a checklist acknowledging that they have gone over and been advised of the implants’ risks.
In February 2016, the FDA ordered Bayer, the manufacturer, to conduct a post-marketing (522) study to further evaluate the safety of the product in real-world application. This study is ongoing and is expected to be completed by 2023.
In November 2016, the FDA also required the manufacturer to add a boxed warning to the product labeling that stated the associated adverse effects. In addition, the FDA required that a more comprehensive patient decision checklist be added to the device labeling.
The new restrictions must be implemented immediately and the FDA will monitor and review the manufacturer’s plans for compliance. The FDA also noted that failure to comply will result in FDA action. Additional action may be required following the results of the post-marketing study.
Can a Pap test one day be used to diagnose ovarian, endometrial cancers?
A foundational study in Science Translational Medicine suggests that cervical fluids gathered during routine Pap tests may have potential in screening for endometrial and ovarian cancers. The findings are from a comparative analysis of samples form women with endometrial or ovarian cancer and controls that were tested with PapSEEK, a test that looks for genetic alterations common in endometrial and ovarian cancers.
For the research, the authors used 1915 samples from 1658 women, 656 of whom had endometrial or ovarian cancer and 1002 of whom were healthy. The researchers noted that tumor DNA can be detected in the vaginal tract of women with ovarian cancer, while endometrial and ovarian cancers shed cells that collect at the cervix. As a result, tumor DNA can be found in the fluids obtained during a routine Pap test.
Because the amount of DNA shed from neoplastic cells was expected to be a small fraction of the total DNA collected from the Pap brush samples, the researchers used a sensitive, PCR-based error-reduction technology to identify mutations. Primers were designed to amplify 139 regions, covering 9392 distinct nucleotide positions within the 18 genes of interest.
The researchers applied this assay to Pap brush samples of 382 women with endometrial cancer, 245 women with ovarian cancer, and 714 women without cancer. Detectable mutations were found in 81% of patients with endometrial cancer (95% CI, 76 to 84%), including 78% of patients with early-stage disease (stages I and II) and 89% of patients with late-stage disease (stages III and IV). In the ovarian cancer patients, 29% had detectable mutations in their Pap brush samples (95% CI, 24 to 36%). This included 28% of patients with early-stage disease and 30% of patients with late-stage disease. Of the women without cancer, 1.3% had a detectable mutation, yielding a specificity of ~99%.
Sensitivity of the assay test was improved by use of a Tao brush, which extends further into the cervical canal. With the tool, PapSEEK identified cancer 93% of the time in the 123 patients studied. Of the 51 ovarian cancer patients studied, 45% tested positive for cancer.
While the authors noted that their findings are promising, they identified a few limitations. The research was retrospective rather than prospective and many of the patients involved in the study had already been diagnosed with cancer, which meant that in many cases, the disease was not in as early a stage as would be expected in a screening setting. Another limitation is that in some patients with ovarian cancer, mutations detectable in Pap or Tao brush samples were not identical to the ones in the primary tumors. While this study is foundational at this point, the authors noted the possible importance of it, given that there is currently no screening test for endometrial cancer.