In patients with initially detected thyroid nodules, core-needle biopsy may be an adequate diagnostic tool and may reduce the need for surgery.
Further, core-needle biopsy revealed high diagnostic accuracy for malignancy as well as low rates of complications and unnecessary surgery, according to the researchers.
Jung Hwan Baek, MD, PhD, of the department of radiology and Research Institute of Radiology at the University of Ulsan College of Medicine and Asan Medical Center in Korea, and colleagues evaluated 632 consecutive patients (mean age, 50.8 years; 136 men) who underwent core-needle biopsy between October 2008 and December 2011 at the University of Ulsan College of Medicine to determine the role of core-needle biopsy as a first-line diagnostic tool for initially detected thyroid nodules.
Core-needle biopsy was performed for the following reasons: suspicious features on ultrasound (n = 145), heavy calcification (n = 118), vascular nodules (n = 88), predominately cystic nodules (n = 3) and referring physician’s preference (n = 278).
Eight of the 634 biopsies (1.3%) resulted in Bethesda category 1. Seventy-three percent of nodules had final diagnoses obtained, and 26.7% were not adequately followed up after the initially detected thyroid nodule. Ninety-three percent of the 211 malignant nodules were diagnosed after surgery, and 7.1% revealed specific pathologic results. There were 254 benign nodules; 9.8% diagnosed after surgery, 20.1% after fine-needle aspiration and/or core-needle biopsy with benign findings at least twice and 70.1% after core-needle biopsy revealed benign findings when the nodule remained stable after 1 year.
Conclusive results were found with core-needle biopsy in 94.2% of cases, and 5.9% had inconclusive results. Thirty percent were diagnosed as malignant. Core-needle biopsy for diagnosing malignant nodules had 97.6% diagnostic accuracy, 90% sensitivity, 100% specificity, 100% positive predictive value and 92.3% negative predictive value. There was an unnecessary surgery rate of 0.5%.
“This study demonstrates that evaluation using [core-needle biopsy] resulted in low rates of Bethesda category 1 and inconclusive results and a high diagnostic accuracy in patients with initially detected thyroid nodules,” the researchers wrote. “[Core-needle biopsy] had a [positive predictive value] of 100%, thus minimizing unnecessary surgery. There were no independent risk factors associated with inconclusive results. These findings indicate that [core-needle biopsy] may be a promising diagnostic tool for patients with initially detected thyroid nodules.” – by Amber Cox
The researchers report no relevant financial disclosures.