FROM JAMA ONCOLOGY
Cancer centers with a high use of neoadjuvant chemotherapy in patients with advanced-stage epithelial ovarian cancer show similar improvements in median overall survival and larger declines in short-term mortality than in centers with low use of this treatment. This is according to a study published in JAMA Oncology, suggesting that neoadjuvant chemotherapy may be a suitable first-line treatment approach for many patients with advanced-stage ovarian cancer.
“There is considerable variation in practice. Some centers administer neoadjuvant chemotherapy to 75% of patients with advanced ovarian cancers, others use the approach very infrequently,” said Alexander Melamed, MD, MPH, of Columbia University, New York.
“I hope that those clinicians who have been worried about the negative impacts of too frequent administration of neoadjuvant chemotherapy may be reassured by this study and may come to use this good treatment more often.”
Research has shown that, compared with primary cytoreductive surgery, the use of neoadjuvant chemotherapy has similar long-term survival and improved perioperative outcomes in patients with ovarian cancer. While the use of neoadjuvant chemotherapy has increased, many experts continue to recommend upfront surgery as the preferred treatment for these patients.
“In part, these recommendations are based on flawed interpretations of real-world data. Specifically, many observational studies have concluded that upfront surgery results in better survival than neoadjuvant chemotherapy, based on study designs that ignored the fact that patients who receive neoadjuvant chemotherapy in the real word are sicker and have more extensive cancer than those who receive upfront surgery,” Dr. Melamed said.
In this difference-in-differences comparative effectiveness analysis, researchers asked if the difference in adoption of neoadjuvant chemotherapy by U.S. cancer centers for advanced-stage epithelial ovarian cancer was associated with differences in median overall survival and 1-year all-cause mortality.
“By assessing how this divergence in practice impacted patient outcomes we were able to infer how frequent use of neoadjuvant impacts survival in ovarian cancer patients. This study design allowed us to sidestep the problem of selection bias that has plagued many other observational studies in this space,” Dr. Melamed explained.
This observational study included 39,299 women with stage IIIC and IV epithelial ovarian cancer, diagnosed between 2004 and 2015 who were followed to the end of 2018, and treated at one of 664 cancer programs. Patients treated in programs that increased neoadjuvant chemotherapy administration had greater improvements in 1-year mortality (difference-in-differences, −2.1%; 95% confidence interval, −3.7 to −0.5) and equivalent gains in median overall survival (difference-in-differences, 0.9 months; 95% CI, −1.9 to 3.7 months), compared with those treated in programs that used the treatment infrequently.
“For a long time, experts have suggested that the apparent discordance between randomized controlled trials and real-world studies that compare neoadjuvant chemotherapy to upfront surgery for ovarian cancer might mean that the randomized trials are not applicable to real-world practice. What is significant about our findings, is that, when more appropriate study methods are used to analyze the real-world data, the apparent contradiction between real-world and randomized studies is resolved.
“We found that, just as one would guess based on the findings of randomized trials, patients treated in the centers that increased the use of neoadjuvant chemotherapy did not have any decrement in long-term survival, but that short-term mortality did improve more in these centers than in centers that administered neoadjuvant chemotherapy rarely,” she said.
Dr. Melamed said that the findings should “spur a reappraisal” of what clinicians consider the default treatment for women with stage IIIC and IV ovarian cancer.
Taken together with randomized controlled trials, “the evidence may be at a point where it is now time to consider neoadjuvant chemotherapy as the default approach to patients with bulky carcinomatosis, and that primary surgery may be a reasonable alternative for a select group of healthy, young patients with low-volume metastasis.
“Other factors like the route of adjuvant chemotherapy may also need to be considered. However, I believe the belief that aggressive primary debulking is beneficial for most women with advanced ovarian cancer is outdated,” Dr. Melamed said.
No relevant conflicts of interest were reported for this research.