May 11, 2015
Several clinical trials have shown that for women with ovarian cancer, intraperitoneal (IP) chemotherapy–which allows the drugs to be delivered directly into the peritoneum at a 20- to 1000-fold greater concentration than intravenous (IV) chemotherapy— confers survival advantages. However, despite the recognized advantages of IP therapy, the practice has not been widely accepted as the standard of care in the United States and is used infrequently in Europe. This hesitation to use IP stems from clinicians’ concerns about IP chemotherapy’s higher toxicity and uncertainty about its long-term benefit.
Based on these concerns, a new Journal of Clinical Oncology (JCO) study, “Long-Term Survival Advantage and Prognostic Factors Associated with Intraperitoneal Chemotherapy Treatment in Advanced Ovarian Cancer: A Gynecologic Oncology Group Study,” sought to answer three questions: One, do the survival benefits of IP therapy extend into the long term? Two, can patients derive the same survival benefits from two or four cycles as from the standard six cycles—thus reducing toxicity? Three, is it possible to pinpoint characteristics that would allow doctors to predict which patients will likely complete all six cycles of IP therapy?
The study, published online, ahead of print, March 23, analyzed data from 876 patients in two Gynecology Oncology Group protocols. Results of the study showed that IP chemotherapy confers a survival advantage that extends beyond 10 years and that the more cycles of IP therapy patients received, the longer they lived; in fact, the risk of death decreased by 12% for each cycle of IP therapy that patients completed. This study is one of the first in advanced ovarian cancer to demonstrate long-term survival benefits associated with IP chemotherapy.
Commenting on the finding that a greater number of cycles is associated with greater survival, study principal investigator, John K. Chan, MD, said, “One of the important things that we found was that you cannot administer a reduced schedule of two or three cycles of IP therapy and finish with IV therapy. What we found is that the more cycles of IP therapy you give, up to six cycles, the more patients benefit.”
As patients age, tolerance to IP Chemo declines
Another one of the study’s important findings is that younger patients were more likely to complete all six cycles. According to Dr. Chan, “One possible reason for this finding is that the younger patients were more able to tolerate the side effects related to IP, allowing them to complete six cycles. Age was the only independent factor predicting tolerance.”
For Dr. Chan, the findings about the long-term benefits of six cycles of IP therapy underscore the importance of referring patients with advanced ovarian cancer to specialized centers. “At specialized centers, patients can undergo optimal cytoreductive surgery by a gynecologic oncologist, followed by IP chemotherapy administered by experts and their team of oncologists and nurses—in essence, a team approach,” said Dr. Chan. “We understand that these patients experience more side effects and that their schedule of treatment is more intense, however, they can also experience long-term survival benefits. In other words, the toxicity is transient but the survival benefits are long-term.”
John K. Chan is a gynecologic oncologist at the Sutter Research Institute at California Pacific/Palo Alto Medical Foundation and adjunct professor at Stanford University; University of California, San Francisco; and Dartmouth University. He is a member of ASCO’s Scientific Program Committee.
Abstract of the original JCO article.
PDF of the original JCO article.
Tewari D, Java JJ, Salani R, et al. Long-term survival advantage and prognostic factors associated with intraperitoneal chemotherapy treatment in advanced ovarian cancer: a gynecologic oncology group study. J Clin Oncol. Epub 2015 March 23.
The Exclusive Coverage series on ASCO.org highlights selected research from JCO and JOP with additional perspective provided by the lead or corresponding author.
@ 2014 American Society of Clinical Oncology