Retroperitoneal exploration at the time of primary debulking surgery appeared to improve survival in patients with intraperitoneal stage IIIC optimally debulked epithelial ovarian cancer, according to data collected from a large multi-institutional trial.
Based on the previous FIGO staging system, “approximately 10% to 25% of patients with presumed early-stage disease confined to the ovaries or pelvis have been upgraded to stage III disease due to retroperitoneal lymph node metastasis identified during thorough surgical staging,” Bunja J. Rungruang, MD, assistant professor of gynecologic oncology at Medical College of Georgia of Augusta University, and colleagues wrote. “Although retroperitoneal and intraperitoneal disease burden are both prognostically important, patients with advanced-stage disease by positive lymph nodes alone have improved survival compared with those with bulky peritoneal disease.”
However, no data support the performance of retroperitoneal exploration or dissection at the time of primary cytoreductive surgery to improve survival in patients with stage IIIC intraperitoneal disease.
Therefore, Rungruang and colleagues used records from the Gynecologic Oncology Group 182 study to evaluate the effect of retroperitoneal exploration on PFS and OS in patients with stage IIIC epithelial ovarian cancer who underwent optimal debulking surgery.
The analysis included 1,871 patients with stage IIIC disease and an intraperitoneal tumor size of 2 cm or larger who underwent primary cytoreductive surgery to no gross residual disease or minimal gross residual disease. Researchers divided patients into three subgroups of those without lymph node involvement (n = 269), with lymph node involvement (n = 420) or with no retroperitoneal exploration (n = 1,182).
In total, 689 patients underwent retroperitoneal exploration with removal of lymph nodes from at least one para-aortic site.
Multivariate regression showed that retroperitoneal exploration was associated with significantly improved PFS (HR = 0.85; 95% CI, 0.76-0.95) and OS (HR = 0.85; 95% CI, 0.75-0.96) compared with no retroperitoneal exploration.
However, multivariable proportional hazards modeling demonstrated no difference in survival between patients who underwent systematic retroperitoneal exploration and those who underwent a selective retroperitoneal exploration for PFS (HR= 0.95; 95% CI, 0.74-1.23) and OS (HR = 1.11; 95% CI, 0.89-1.38).
Patients who underwent retroperitoneal exploration demonstrated improved PFS (18.5 months vs. 16 months) and OS (53.3 months vs. 42.8 months). This trend continued in patients with minimal gross residual disease in terms of PFS (16.8 months vs. 15.1 months) and OS (44.9 months vs. 40.5 months).
Among patients who underwent retroperitoneal exploration, those without lymph node involvement demonstrated superior PFS (22.1 months vs. 17.2 months) and OS (63.1 months vs. 45.9 months) compared with those with lymph node involvement.
“Even if preoperative imaging is negative for lymphadenopathy, our data suggest that when minimal or no gross residual is achieved, a retroperitoneal nodal exploration should be performed based on a potential survival benefit that may be conferred by the performance of the dissection,” the researchers wrote. – by Kristie L. Kahl
Disclosure: The researchers report no relevant financial disclosures.