New Surgical Algorithm Results in Improved Complete Resection Rates in Advanced Ovarian Cancer
A surgical algorithm developed and implemented by ovarian cancer specialists at The University of Texas MD Anderson Cancer Center dramatically increases the frequency of complete removal of all visible tumor—a milestone strongly tied to improved chances of survival.
The researchers describe the Anderson Algorithm in a perspective piece by Nick et al outlining a personalized surgical approach to ovarian cancer in Nature Reviews Clinical Oncology.
“Our algorithm allows us to be much smarter about whom we operate on upfront, providing a more individualized approach to surgery that’s led to better results for our patients,” said Anil Sood, MD, Professor of Gynecologic Oncology and Reproductive Medicine, and senior author of the paper.
The multistep process was developed through MD Anderson’s Moon Shots Program, an ambitious effort launched in 2012 to dramatically reduce cancer deaths. Dr. Sood is Co-Leader of the Breast and Ovarian Cancer Moon Shot. “We worked hard to develop this algorithm, but all of it is based on existing knowledge,” he said.
Surgeons gathered to focus on a quality improvement program to address a central issue in treating advanced ovarian cancer: how to optimize surgery to achieve complete removal of all visible tumor, also called optimal resection.
A combination of surgery and chemotherapy is used to treat the disease, but the sequence of those therapies has been at issue for lack of clear indication of which should be used first. Practice at MD Anderson varied among physicians, Dr. Sood said.
Increased Rates of Complete Resection
Since surgeons began to apply the Anderson Algorithm, the rate of complete resection for patients who have surgery first has gone from around 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. Physicians have 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. Specialists note that it’s the strongest independent variable predicting overall survival. For example, data from seven multi-institutional U.S. clinical trials showed patients who had 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 overall.
Laparoscopy-Based Predictive Index
Alpa Nick, MD, Assistant Professor of Gynecologic Oncology, and colleagues also note that computed tomography (CT) imaging and analysis of bloodborne 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 below 8 indicates for surgery first, while a score of 8 or above indicates presurgical chemotherapy.
“Ovarian cancer spreads like a coating over other organs, which is one of the reasons CT scans are less effective,” Dr. Nick said. “Laparoscopy allows a better visual assessment of the disease.”
The Anderson Algorithm
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.
- Two surgeons to independently score the disease for potential to remove all visible tumor.
- A third surgeon to score the disease if the first two disagree in their assessment.
- Patients with scores under 8 are scheduled for surgery; those at 8 or above first proceed to three rounds of chemo with responders then going to surgery.
So far, the first two surgeons have agreed 98% of the time.
Dr. Sood and Dr. Nick have presented the Anderson Algorithm in a variety of settings at medical meetings or to other institutions, and noted that interest in adopting it has been high. They are working with academic cancer centers and private providers to expand use of the algorithm.
Dr. Nick is the corresponding author for the Nature Reviews Clinical Oncology article.
The content in this post has not been reviewed by the American Society of Clinical Oncology, Inc. (ASCO®) and does not necessarily reflect the ideas and opinions of ASCO®.
