Dr. Rebecca Smith-Bindman, professor of radiology at UCSF
Thyroid ultrasound can help reduce unnecessary biopsies, a new study published in JAMA finds.
A team of researchers led by Dr. Rebecca Smith-Bindman analyzed data from the California Cancer Registry of patients who underwent thyroid ultrasound imaging from January 1, 2000, through March 30, 2005. Of the 8806 patients who were examined, 105 were diagnosed with thyroid cancer.
Diagnosing thyroid cancer can be especially tricky since not all thyroid nodules are cancerous —- in fact, over 98 percent of thyroid nodules are benign, according to experts.
Smith-Bindman and her team were struck by how dramatically the criteria for biopsy varied from physician to physician.
They realized that though large numbers of patients were being referred for thyroid ultrasound due to nodules detected on other imaging tests, there was little research on how common these nodules were or how likely they were to be cancerous.
"So the project was motivated by a desire to improve clinical practice," Smith-Bindman told DOTmed News.
Three characteristics identified using ultrasound set cancerous nodules apart from non-cancerous nodules, researchers found: microcalcification, size and solid composition.
Current criteria requires a biopsy if the nodule is larger than 5 millimeters, but using these characteristics to raise the threshold for biopsies and diagnosis could potentially reduce false positives and reduce unnecessary biopsies by 90% while maintaining a low risk of cancer.
In recent years doctors have voiced criticism around screenings that increase false positives and unnecessary biopsies.
A panel associated with the National Cancer Institute accordingly recommended narrowing the definition of cancer to exclude certain commonly diagnosed diseases with low risk of malignant growth.
And numerous other studies show that using more specific, stringent criteria can reduce false positives, biopsies and patient anxiety.
