A research team at Seoul National University Bundang Hospital (SNUBH) has found that preoperative ultrasound alone can predict tumor burden and surgical complexity in patients with advanced ovarian cancer, potentially offering a new tool to guide treatment strategies.

Traditionally, imaging tests such as CT or MRI have been used to assess tumor size and location before surgery. However, ovarian cancer often spreads through small, widespread peritoneal seeding that is difficult to detect with conventional imaging. This has sometimes led to mismatches between surgical planning and intraoperative findings, resulting in unexpected changes to the surgical scope.

To address this gap, the team, led by Professor Kim Ki-dong of the Department of Obstetrics and Gynecology, conducted a study of 85 patients with advanced ovarian cancer who underwent surgery at three hospitals between 2022 and 2023. Based on ultrasound scans taken before surgery, the team classified tumor seeding into four types: no seeding, reticular nodules (small nodules spread in a web-like pattern), thin serosal plaques (diffuse but shallow spread), and bulky masses (large, dense spread).

During surgery, tumor burden and surgical complexity were scored. Tumor burden was measured using a standardized index that divided the abdominal cavity into 13 regions, with a maximum score of 39 points. Surgical complexity reflected the extent of organ invasion.

Results showed a clear correlation between ultrasound findings and actual surgical outcomes. Patients with no seeding had an average tumor burden score of 4.7 and a surgical complexity score of 2.3. In contrast, those with bulky seeding had significantly higher scores of 12.5 and 5.6, respectively.

Notably, the presence of seeding also predicted the likelihood of additional bowel surgery, such as rectal resection. While 33 percent of patients without seeding required bowel surgery, the proportion rose to 61 percent in those with seeding, indicating that ultrasound assessment could provide early guidance on surgical planning.

“This study shows that ultrasound, which can be performed easily during outpatient visits, has strong predictive value for tumor burden and surgical difficulty in ovarian cancer,” Professor Kim said. “Identifying seeding patterns in the Douglas’ pouch before surgery could help optimize surgical strategies and improve patient-tailored treatment.”

The findings were published in the European Journal of Surgical Oncology.