Mainstreaming of Genetic Testing Is Tied to Increased Testing Rates in Ovarian Cancer

Ying Liu, MD, MPH

Seamlessly integrating genetic testing into gynecologic oncology clinics may lead to increased genetic testing rates among patients with ovarian cancer, according to Ying Liu, MD, MPH. Additionally, mainstreaming efforts may widen the scope of genetic testing to reach patients who have certain disease characteristics or are part of certain demographics that make them less likely to receive this testing, Tiffany Sia, MD, added.

At the 2024 SGO Annual Meeting on Women’s Cancer, Liu and Sia presented findings from a study that evaluated the effects of mainstreamed genetic testing among patients with newly diagnosed epithelial ovarian cancer who received care at Memorial Sloan Kettering Cancer Center in New York, New York. Findings showed that among 1742 patients, 91.3% underwent genetic germline testing vs 8.6% who did not undergo testing.

“Doing the [genetic testing] process together [with gynecologic oncology care] and streamlining it takes mainstreaming to the next level,” Liu said in an interview with OncLive^® during the 2024 SGO Annual Meeting.

“We should still continue to enforce universal recommendations for germline genetic testing,” Sia added in the interview.

Tiffany Sia, MD

In the interview, Liu and Sia discussed the far-reaching benefits of performing genetic testing in patients with ovarian cancer, how the findings from this research support the mainstreaming of genetic testing and questions that remain to be answered through future research.

Liu is a gynecologic oncologist and clinical geneticist at Memorial Sloan Kettering, where she is also the leader of the Inherited Gynecologic Cancer Program.

Sia is a gynecologic oncology fellow at Memorial Sloan Kettering.

OncLive: What was the rationale for exploring the effect of mainstreaming genetic testing for patients with ovarian cancer?

Liu: Genetic testing in ovarian cancer is so important. It's been a universal recommendation for over 10 years. However, unfortunately, studies have shown that not all women are getting tested; approximately only one-third of women [with ovarian cancer undergo testing]. We’re investigating novel ways to get more women tested. One [way] has been to implement genetic testing into the oncology clinic and do it simultaneously with the oncology work. That's what we looked at in our own clinics.

What makes genetic testing so vital for patients with ovarian cancer?

Liu: Genetic testing is so important in ovarian cancer because approximately 15% to 20% of women with ovarian cancer have [this disease] because of a genetic reason they were born with, which they can pass on to their children and that can affect their family members.

[Genetic testing is] important for 2 reasons. One, it affects treatments, because certain targeted therapies, such as PARP inhibitors, are beneficial in women with mutations in genes such as BRCA1, BRCA2, and others. That's important to know for their treatment because these treatments have improved cure rates and overall survival outcomes [in patients harboring these mutations].

The second reason [genetic testing] is so important is for cancer prevention [for patients’] family members. When women with ovarian cancer get genetic testing, this can lead to cascade testing for their family members and gives them an opportunity to prevent ovarian cancer through risk-reducing measures.

What is the definition of "mainstreaming," as outlined in this research?

Sia: ‘Mainstreaming’ is defined as the integration of genetic testing directly into oncology clinics. Traditionally, after the oncologist met with the patient and determined if they were a candidate for genetic testing, they would make a referral to a genetics counselor, who would set up a separate appointment to meet with the patient, counsel them, run the test, and give them the results.

Mainstreaming was implemented in January 2019 for patients with ovarian cancer [at Memorial Sloan Kettering]. With the implementation of mainstreaming, the oncologist would meet with the patient, counsel them about genetic testing, order the testing, and perform the testing themselves. The patient would leave a blood sample, and the oncologist would go over the result with the patient. In cases of a positive finding, the patient would be referred to a genetics counselor to discuss the implications [of this finding] and talk about cascade testing for other family members.

Liu: The mainstreaming in our study and at Memorial Sloan Kettering is unique because we do it in an integrated fashion with tumor testing. We do it through something called MSK-IMPACT, where patients get simultaneous genetic or germline testing with their tumor testing.

What were the key findings from this study?

Sia: We wanted to determine how the implementation of mainstreaming affected the percentage of patients who underwent germline genetic testing within Memorial Sloan Kettering. Prior to mainstreaming, the average percentage of patients who underwent germline genetic testing was 87% [at Memorial Sloan Kettering from 2015 to 2018]. After the implementation of mainstreaming, that number jumped to 91.3%. The rate of patients who underwent testing per year increased over time.

[We evaluated] patient factors, such as age; self-reported race and ethnicity; and type of primary treatment, such as primary debulking surgery or neoadjuvant chemotherapy. We also assessed social demographic factors, such as Yost score, which is a measure of a neighborhood’s socioeconomic status based upon the patient's zip code; marital status; education; insurance; and National Cancer Institute comorbidity index. On multivariable analyses, mainstreaming was significantly associated with increased odds of genetic testing, even after adjusting for [factors] such as receipt of neoadjuvant chemotherapy, [disease] stage, and histology.

What next steps are planned for this research?

Liu: This research showed us that testing rates with our current method are high, but it found specific areas where we could improve our efforts. One of the ways we are working on improvements is a quality improvement project to try to make this process even more seamless and patient-directed.

One of the [benefits to come from the COVID-19 pandemic] in the genetics field is that it led to a lot of telemedicine and telegenetics, and it gave patients the power to self-direct their genetic testing. That's one of the aspects we want to incorporate into this mainstreaming process to see if that will further improve genetic testing rates and specifically help with some of the disparities we found. Additionally, some of our multivariable models revealed that patients with nonserous disease histologies who are not married and [have] other clinical factors might be less likely to get genetic testing. These are areas we can focus on.

What are the future implications of these findings?

Sia: Our findings show that germline genetic testing should be recommended and performed in all patients with epithelial ovarian cancer, regardless of histology, age, or self-reported race or ethnicity. We highlighted the factors that are associated with decreased testing rates. Even though this [study was conducted] within Memorial Sloan Kettering, the findings can be applied throughout all of [the United States].

What is your main message for colleagues regarding the importance of genetic testing in patients with ovarian cancer?

Liu: Do the genetic testing [through whatever means necessary] to get it done. We need to achieve that 100% [testing rate]. Try to integrate [genetic testing] with tumor testing, because then you can get [findings from 2 tests at 1 time] and get more information for the patient.

Reference

Sia Y. Mainstreaming in gynecologic oncology clinics triples the odds of genetic testing in patients with epithelial ovarian cancer. Presented at: 2024 SGO Annual Meeting. March 16-18, 2024; San Diego, California.