Algorithm increases surgical success in advanced ovarian cancer
The frequency of complete removal of all visible tumor is dramatically increased by a surgical algorithm developed and implemented by ovarian cancer specialists. This personalized surgical approach to ovarian cancer was described in a perspective piece in Nature Reviews Clinical Oncology (2015; doi:10.1038/nrclinonc.2015.26).
"Our algorithm allows us to be much smarter about whom we operate on up front, providing a more individualized approach to surgery that's led to better results for our patients," said senior author Anil Sood, MD, professor of Gynecologic Oncology and Reproductive Medicine at The University of Texas MD Anderson Cancer Center in Houston.
Since surgeons began to apply the Anderson Algorithm, the rate of complete resection for patients who have surgery first has gone from approximately 20% to 88%, and for those receiving chemotherapy first it has improved from 60% to 86%. The algorithm so far has sorted half of patients to each mode of treatment. Faculty adhered to the algorithm 95% of the time since it began 2 years ago.
The article reviews the clinical evidence for increased survival among patients with no residual disease after surgery. They note that it's the strongest independent variable predicting overall survival. For example, data from seven multi-institutional US clinical trials showed patients with no visual residual disease had a median survival of 64 months compared with 29 months for those with minimal residual cancer.
A major clinical trial randomizing patients to either initial surgery followed by chemotherapy or chemotherapy then surgery revealed no significant difference in overall survival between the groups. However, those who achieved complete resection within either group did much better.
First author Alpa Nick, MD, assistant professor of Gynecologic Oncology, and colleagues also note that computed tomography (CT) imaging and analysis of blood-borne proteins associated with ovarian cancer, such as CA-125, have so far failed to predict which patients would benefit from surgery first.
The paper cites research that showed examining patients via laparoscopy is highly predictive of the likelihood of achieving optimal tumor resection.
Anna Fagotti, MD, and colleagues at Catholic University of the Sacred Heart in Rome, developed a predictive index based on the extent of disease identified by laparoscopy on seven other organs. A score of less than 8 is indicative for surgery first, whereas a score of 8 or higher indicates presurgical chemotherapy.
"Ovarian cancer spreads like a coating over other organs, which is one of the reasons CT scans are less effective," Nick said. "Laparoscopy allows a better visual assessment of the disease."
Under the MD Anderson quality improvement plan, a consensus was reached to offer presurgical chemotherapy to patients in whom complete surgical removal is unlikely. The plan also calls for disease assessment by expert colleagues in liver, thoracic, colorectal, or urologic oncology when indicated.
The Anderson Algorithm calls for diagnostic laparoscopy for all surgically fit patients with suspected advanced-stage ovarian cancer. Also, two surgeons independently score the disease for potential to remove all visible tumor. Then, a third surgeon scores the disease if the first two disagree in their assessment.
Patients with scores below 8 are scheduled for surgery; those at 8 or higher receive three rounds of chemotherapy first with responders then proceeding to surgery.