ORLANDO – Improper surgery, a lack of lymph node assessment, and improper or no chemotherapy top the list of reasons that women with ovarian cancer do not receive care consistent with National Comprehensive Cancer Network guidelines, according to a study of nearly 100,000 patients.
"Overall, we were quite sad to see that only 43% of patients appear to be receiving care adherent with the NCCN guidelines," Dr. Matthew A. Powell said at this year’s annual meeting of the Society of Gynecologic Oncologists (SGO). "The reasons for nonadherence were mostly surgical in nature."
Dr. Matthew A. Powell
Researchers assessed treatment of 96,802 women diagnosed with invasive epithelial ovarian cancer in the National Cancer Database from 1998 to 2007. They also evaluated mature 5-year survival data from 1998 to 2002.
To determine guideline adherence, Dr. Powell and his associates noted initial surgical procedure and initial front-line chemotherapy. They also assessed compliance by cancer stage, substage, and grade.
The primary reason for nonadherence was a lack of documented omentectomy (54,939 or 57% of the nonadherent cases). "In those patients who did have an omentectomy and stage I to IIIb cancer, we required them to have lymph node assessment," Dr. Powell said. "Unfortunately this also represented a large portion of the nonadherence."
Improper chemotherapy comprised the remainder of nonadherent cases, where patients received single-agent chemotherapy, no chemotherapy, or inappropriate chemotherapy based on cancer stage and grade.
Patients who underwent surgery only (with no evidence of chemotherapy in their records) included a large portion with stage IIIc and IV disease, Dr. Powell said. Only 8% of this cohort received care consistent with the National Comprehensive Cancer Network (NCCN) guidelines.
"One-third of patients had two or three reasons to be nonadherent to the guidelines," said Dr. Powell, who is on the obstetrics and gynecology faculty, Division of Gynecologic Oncology at the Washington University, St. Louis.
The NCCN established the ovarian cancer guidelines in 1997, and they underwent regular revisions, including major updates in 2000 and 2006, Dr. Powell said.
One aim of the study was to determine the validity of NCCN ovarian cancer clinical practice guidelines using a survival comparison. Adherence to the guidelines "does seem to correlate with improved survival and, perhaps, with better quality care. It translates to approximately a 13-month improved median survival for patients who were compliant," Dr. Powell said, adding this difference was "highly statistically significant" (hazard ratio, 1.44).
Adherence and survival correlated across each stage of cancer as well, Dr. Powell said.
During a Q & A session, Dr. Barbara Goff pointed out that some noncompliant care was delivered to patients at one of the 21 major institutions that form the NCCN. "I was surprised that only about 50%-55% of the time were patients at NCCN institutions receiving guideline-based therapy," said Dr. Goff, professor of gynecologic oncology at the University of Washington, Seattle.
"We were quite surprised adherence was that low at centers that write the guidelines," Dr. Powell responded. A higher percentage of referred patients, a lack of information on patients who intentionally decline treatment, and/or less-than-ideal documentation in the database could be contributing factors, he said. "This is obviously a focus for future research."
Patient, tumor, and treatment characteristics were considered in the 5-year survival analysis. "As we all would guess, stage was predictive, with advancing stage [associated] with worse survival," Dr. Powell said. Patients with higher grade cancers also fared worse.
Dr. Powell and his associates also assessed their data according to center volume. For example, in the lowest volume centers (with one to six cases per year), adherence was 40% and median survival was 31 months. At the highest volume centers (with 26 or more cases per year), adherence was 55% and median survival increased to 46 months.
Asked if factors such as increasing age and comorbidity could result in nonadherent, yet appropriate care, Dr. Powell responded. "It’s clear patients with more comorbidities tend to not have NCCN-compliant care." He added, "We want to set a bar and evaluate based on that bar, but it doesn’t mean there cannot be exceptions, patient factors and others.
"We need to measure what we are doing before we can improve," Dr. Powell said. The Society of Gynecologic Oncologists just created a Quality and Data Outcomes Committee designed to assess and measure quality of care as physician performance comes under increased reimbursement pressure in the next few years.
Dr. Powell said he had no relevant disclosures.