Investigating Surgical vs Liquid Biopsy for Ovarian Cancer MRD

Amir Jazaeri, MD, of MD Anderson Cancer Center, shared insights from a groundbreaking study on the use of second-look laparoscopy and liquid biopsy in managing ovarian cancer. He began by highlighting that investigating residual disease with a second surgical procedure is a relatively new approach in the modern management of this disease. The primary objective of their investigation was to understand the prognostic value of a second surgery—specifically, a second-look laparoscopy—to determine outcomes in patients with documented residual disease versus those without.

As they were beginning this study, Jazaeri and his team were also aware of a promising new development in the field: the liquid biopsy, a noninvasive blood test. More specifically, they were interested in circulating tumor DNA (ctDNA), a type of liquid biopsy that can detect genetic material shed by cancer cells into the bloodstream. They anticipated that this molecular test might also provide valuable information about minimal residual disease (MRD). To test this hypothesis, they established a protocol where patients undergoing a second-look laparoscopy could volunteer to donate additional tubes of blood. This blood was then banked for future analysis of ctDNA. The ultimate goal was to compare the ability of ctDNA and surgery to detect MRD.

Through a collaboration with Natera, a company specializing in ctDNA assays, they used what is arguably the most widely utilized commercial assay available. The study sought to answer 2 key questions: First, how does the ctDNA test compare to surgical findings in detecting residual disease? Second, and independently, what prognostic information does each method—surgical MRD and molecular (ctDNA) MRD—provide?

The findings were revealing. Of the patients who were found to have residual disease through surgery, approximately half were also detected by the ctDNA blood test. Interestingly, there were also a small number of patients who were negative for residual disease by surgery but tested positive via the blood test. When they analyzed the prognosis for these different patient groups, the results were clear: a positive result for residual disease, whether by surgical examination or the ctDNA assay, was associated with a poorer prognosis.

Jazaeri also provided an important caveat regarding the patients who tested negative. A negative result from either test does not mean the cancer will never recur. Instead, it indicates that recurrence is less likely and, on average, occurs much later than in patients who are positive for residual disease by either the surgical or the molecular assay. This study underscores the potential of combining both surgical and molecular approaches to provide a more comprehensive picture of a patient's prognosis and guide more personalized treatment strategies for ovarian cancer.