Secondary cytoreductive surgery was not associated with improvement in either OS or PFS in patients with platinum-sensitive recurrent ovarian cancer.
Secondary cytoreductive surgery was not associated with improvement in either overall survival (OS) or progression-free survival (PFS) over no surgery in patients with platinum-sensitive recurrent ovarian cancer. Results of the Gynecologic Oncology Group (GOG)-0213 trial (abstract 5501) were presented at the 2018 American Society of Clinical Oncology (ASCO) Annual Meeting, held in Chicago.
“Given the anticipated chemosensitive nature of this cohort…it’s not surprising that secondary surgery ahead of chemotherapy has been recommended, particularly among those that are medically fit, with long disease-free intervals, and limited resectable disease,” said Robert L. Coleman, MD, of the University of Texas MD Anderson Cancer Center in Houston. There are many previous studies exploring this approach, but Coleman said the vast majority are retrospective, single-institution, or suffer from obvious biases that make interpretation difficult.
The GOG-0213 trial had two objectives; the results of the first objective, to study the addition of bevacizumab to paclitaxel/carboplatin concurrently and as maintenance, were previously reported. In the full trial, women with recurrent ovarian, peritoneal, or fallopian tube cancer who were eligible for surgery were randomized to undergo cytoreductive surgery or not, while ineligible patients were randomized immediately for treatment with chemotherapy with or without bevacizumab. In the surgical cohort, a second randomization was done for the systemic therapy, though this was amended part way through the trial so that the systemic therapy was by physician’s choice.
The results that Coleman reported on included 485 patients, 229 from Korea and Japan and 256 from the United States. They were randomized to either the surgery arm (240 patients, 239 eligible) or the no-surgery arm (245 patients, 243 eligible). Most patients went on to receive a bevacizumab-containing regimen (86%).
Of the patients who underwent cytoreductive surgery, 64% had an R0 resection on an intent-to-treat analysis; this rate was 68% of the per-protocol population, as 14 patients did not undergo surgery. There was a median follow-up of 34.6 months.
The median OS was 53.6 months with surgery, and 65.7 months without it, for a hazard ratio (HR) of 1.28 (95% CI, 0.92–1.78). Similarly, PFS was no different between the groups, with a median of 18.2 months with surgery and 16.5 months without it, for an HR of 0.88 (95% CI, 0.70–1.11).
Patients with an R0 resection appeared to fare better than non-R0 resection patients with regard to PFS, with an HR of 0.51 (95% CI, 0.36–0.72), but this was an exploratory analysis. OS was still not significantly different between R0 and non-R0 resection patients. When compared with no surgery, R0 resections were again associated with better PFS but not OS; again, this was considered exploratory.
“Secondary surgical cytoreduction did not improve either OS or PFS in this population,” Coleman concluded, noting that the results were similar in both the Asian and US cohorts.
Ginger J. Gardner, MD, of Memorial Sloan Kettering Cancer Center in New York, was the discussant for the session. “The trial demonstrates that secondary cytoreductive surgery is safe and feasible,” she said. She noted, though, that the high performance of the non-surgical group who were eligible for surgery raises questions about the criteria used for the accrual and randomization. Case selection, she said, remains controversial at this point.