Guidelines for Molecular/Cytogenetic Tests Can Eliminate Overordering, Reduce Costs
Instituting guidelines-based test ordering could lead to more effective, accurate, and complete diagnosis and monitoring of hematolymphoid malignancies, while reducing costs, according to hematopathologists at Vanderbilt University Medical Center, Nashville, who said that tests were frequently overordered by their hematologists.
Molecular and cytogenetic testing is critical in the diagnosis and management of hematologic malignancies, but these can be complex and expensive. No comprehensive guidelines exist for the disease- and patient-specific selection of these tests.
The Hematopathology Diagnostic Management Team explored the hypothesis that there is significant variability in test-ordering patterns, including overordering of unnecessary tests and underordering of necessary tests. They established evidence-based standard operating procedures for molecular and cytogenetic test ordering, which pathologists would apply after a review of the patient’s clinical history and bone marrow morphology. These standards were then compared with current practices at Vanderbilt.
“We found that if we followed the guidelines in all cases, and eliminated excess testing, we would save our payers $1.25 million a year,” said Adam C. Seegmiller, MD, PhD, a hematopathologist who led this study.
“Before we instituted this, we found that clinicians had a tendency to overorder tests, when doing molecular cytogenetic testing before the bone marrow biopsy was done,” Dr Seegmiller said. “We created a standard operating procedure based on current guidelines, best evidence, and best clinical practice. We decided what tests should be ordered for 6 categories of disease and their stages. It’s a very simple chart.”
They evaluated 3007 ordered tests on 804 bone marrow biopsy specimens; this included 769 karyotypes, 1790 fluorescence in situ hybridization assays, and 448 molecular tests. Comparing how clinicians ordered (or did not order) tests with this new standard operating procedure showed that:
- Only 1927 tests (64%) were concordant with the new guidelines
- 1080 tests (36%) were discordant
- 307 tests were omitted that would have been recommended by the new guidelines.
“Over one third were tests that the guidelines would not have recommended [ie, overordered], while 307 tests should have been ordered but were not,” Dr Seegmiller noted.
By stage and clinical scenario, for example, there was 99% concordance between clinicians’ ordering and guidelines for the diagnosis of myeloma, but 0% concordance for testing during follow-up, and 0% posttransplant. For lymphoma, concordance was 81% for diagnosis, 41% for staging, 13% for follow-up, 70% pretransplant, and 32% posttransplant.
“Among discordant tests, only 4% came back positive [ie, detected a mutation], but more than one third of these were redundant. They were positive, but we would have caught these cases elsewhere,” he said. Only 1% of cases were true positives that would have been missed.
“We think we are not only eliminating unnecessary tests, but also increasing the effectiveness of the tests we are using,” Dr Seegmiller added.
“We have now given hematologists the option to turn over all the testing decisions to the hematopathologists, and about 80% of the time our clinicians do that,” he said. Using this new standard, “the hematopathologist makes a decision for testing based on the patient’s clinical history, the appearance of the bone marrow morphology, and the guidelines.”