New Swab Test for Endometrial Cancer Could Offer Easier Diagnosis

A new non-invasive test being studied in clinical trials at Columbia University Irving Medical Center and 11 other medical centers across the country may soon offer a simpler, more comfortable way to diagnose endometrial (uterine) cancer. Cases of endometrial cancer are rising in the Unites States, and the approach could potentially spare many women from an invasive biopsy, which is currently the standard test. 

The test, developed by PinkDx, uses a clinician-collected vaginal swab instead of a biopsy to detect endometrial cancer in women who are already experiencing symptoms. Early results from company-led studies have shown promising accuracy, and the test is now being evaluated in larger clinical validation trials across multiple sites, including Columbia. 

If clinical trials show success, the test could become available in U.S. clinics as early as mid-2027. 

A common cancer with a difficult exam 

Endometrial cancer, which starts in the lining of the uterus (endometrium), is the most common gynecologic cancer. Right now, diagnosing the disease often requires a combination of imaging and an endometrial biopsy. 

“It’s a pelvic exam, where we insert a small plastic suction tubing into the uterus,” describes June Hou, MD, MBA, gynecologic oncologist, and principal investigator (PI) for the PinkDx PNK002 (PROACTION) clinical trial at Columbia. “The test can be quite uncomfortable. I would say it’s at least moderate on the pain scale, even with local anesthesia.” 

More than 90% of endometrial cancer cases are first identified after abnormal uterine bleeding. However, it’s difficult to pinpoint what is considered ‘abnormal bleeding,’ and women are faced with either undergoing an invasive procedure or potentially delaying a critical diagnosis. 

“Women have irregular bleeding and symptoms so often, especially around perimenopause,” Hou says. “One of the fallbacks is to do this endometrial biopsy to rule out precancer or cancer as a cause. However, it’s invasive, and we have long been wanting a better, more non-invasive molecular test to diagnose these changes on a wider scale.” 

A simple swab, a shift to women-centered care 

A non-invasive diagnostic could make {endometrial biopsies} a lot easier for patients.

When patients come to their physician for abnormal bleeding, there is always concern that something serious could be going on, Hou explains. But in many cases, the risk of cancer overall is usually low. 

Still, because abnormal bleeding is common and endometrial biopsy is the standard of care, many patients undergo an invasive procedure as part of their evaluation. 

“This is where we think there is room to improve,” says Hou “We are offering a lot of women endometrial biopsy or surgery, but the majority of times, the cause for bleeding is benign. A non-invasive diagnostic could make this step a lot easier for patients.” 

The PinkDx test is designed to be done in a clinic using a simple vaginal swab collected by a clinician and does not require a speculum exam. The sample is then sent to the PinkDx laboratory in California, with results returned in about two weeks. Based on those initial results, clinicians proceed with standard of care—whether through an office biopsy or a dilation and curettage (D&C) procedure in the operating room. 

Unlike early detection screening tools such as the Pap smear for cervical cancer, the PinkDx test is not intended for the general population. Instead, it is used for women who already have symptoms, most commonly abnormal uterine bleeding. 

The goal, Hou adds, is not to replace clinical evaluation, but to refine how patients are triaged and diagnosed—meeting the need for less painful gynecologic procedures, a shift also seen in newer at-home cervical cancer screening tools designed to reduce the need for speculum-based pelvic exams.

Rising rates drive persistent disparities 

Endometrial cancer is rising by thousands annually, even as many other cancers have stabilized or declined globally- and significant disparities exist. Black women experience significantly higher mortality from endometrial cancer compared with white women. 

“These disparities are significant across social, economic, and racial groups,” Hou says. “That is why there is such a focus on this cancer at the moment, and why Columbia was approached to join the trial because of our patient populations.” 

Columbia has been a key recruitment site for the PinkDx trial, helping ensure that study populations reflect diverse communities. 

“Since opening the trial at Columbia within the last year,” Hou says, “we have consistently been among the top recruiters for enrolling women in the trial.” 

About 30% of participants are women of color, an important step in ensuring the test is accurate across all populations.

The PinkDx trial is part of a broader shift toward less invasive, more patient-centered approaches to diagnosing cancer. Researchers hope these advances will make it easier for women with symptoms to receive timely diagnoses.