4:03 PM Abstract No. 98 Initial large core needle biopsy (LCNB) of suspicious thyroid nodules: sequential cohort series without and with cytopathologist rapid onsite evaluation (ROSE)

Abstract

Thyroid nodule biopsy can have inadequate or indeterminate results and frequently requires re-biopsy. This study was done using a 14-gauge large core needle (LCNB) for initial biopsy of suspicious nodules to evaluate: 1) safety and efficacy; 2) reduction of non-diagnostic (ND) and uncertain (AUS/FLUS) results; and 3) use of rapid on-site evaluation (ROSE) by a cytopathologist. A total of 308 thyroid biopsies of a solitary (180) or largest (128) nodule were done with ultrasound guidance using a 14-gauge large core needle. The patients were divided into two sequential cohort groups: the first group of 152 patients. (49%) with LCNB biopsy cores judged adequate by the interventionalist and the second group 156 patients. (51%) using rapid on-site evaluation (ROSE) by a cytopathologist. The two groups were matched for age range and average (22-82 years, avg. 56 years in group one and 21-84, avg. 57 years in group two) and nodule size (1-4 cm in group one and 1-4.8 cm in group two, avg. 1.8 cm each). Malignant biopsy results and AUS/FLUS and FN/SFN were compared to surgical pathology and benign results to follow-up. LCNB biopsy malignancy rate was 26.9% in the first group and 28.1% in the second group. In the first group, two cases interpreted as atypical cells (category 3 AUS/FLUS) and were upgraded to malignancy at surgery. In the second group, one lesion was category 4 FN/SFN and upgraded to malignant at final surgical histology. The rest showed concordance with surgical pathology. Sensitivity was 98.8%, in the first group and 99.4% in the second group. No false positives were recorded, yielding a specificity of 100% in both cohort groups. Accuracy was 98.0% in the first group and 98.7% in the second group. No unsatisfactory (category 1) results were seen. Benign results were followed for an average of 3.8 years (1-9 years.), no benign cases developed malignancy. No cases of needle tract seeding or laryngeal nerve injury were seen. 1. LCNB can be performed safely and effectively. 2. LCNB reduces non-diagnostic and uncertain category diagnoses in the initial biopsy of suspicious thyroid nodules. 3. Rapid onsite evaluation (ROSE) cytopathology decreases the number of cores needed.