E Chaigneau, G Russ, B Royer, C Bigorgne, M Bienvenu-Perrard, A Rouxel, L Leenhardt, L Belin, and C Buffet
Thyroid nodules with cytological indeterminate results represent a daily and recurrent issue for patient management.
The primary aim of our study was to determine if TIRADS (Thyroid Imaging Reporting and Data System) could be used to stratify the malignancy risk of these nodules and to help in their clinical management. Secondary objective was to estimate if this risk stratification would change after reclassification of encapsulated non-invasive follicular variant of papillary carcinomas (FVPTC) as non-invasive follicular thyroid neoplasm (NIFTP).
Patients and methods
Single-center retrospective study of a cohort of 602 patients who were referred for ultrasound-guided fine-needle aspiration from January 2010 to December 2016 with an indeterminate cytological result and in whom histological results after surgery were available. TIRADS score was prospectively determined for all patients included. Nodules that had been classified as FVPTC were submitted to a rereading of histological report and reclassified as NIFTP when judged relevant. A table of malignancy risk crossing Bethesda and TIRADS results was built before and after this reclassification.
The study included 602 cytologically indeterminate nodules. TIRADS score was positively correlated with the malignancy rate (P < 0.0001). Risk stratification with TIRADS was significant only in Bethesda V nodules (P = 0.0004). However, the risk of malignancy in this Bethesda V category was always above 45%, whatever the TIRADS score.
For a clinician facing an indeterminate cytological result for a thyroid nodule, return to TIRADS score is of limited value in most conditions to rule in or rule out malignancy and to guide subsequent management of patients.
A Rozenbaum, C Buffet, C Bigorgne, B Royer, A Rouxel, M Bienvenu, N Chereau, F Menegaux, L Leenhardt, and G Russ
Active surveillance of cytologically proven microcarcinomas has been shown as a safe procedure. However, fine needle aspiration biopsy (FNAB) is not recommended by European Thyroid Association (ETA) and American Thyroid Association (ATA) guidelines for highly suspicious nodules ≤ 10 mm. The aim of the study was to assess the outcomes of active surveillance of EU-TIRADS 5 nodules ≤ 10 mm not initially submitted to FNAB.
Patients and methods
80 patients with at least one EU-TIRADS 5 nodule ≤ 10 mm and no suspicious lymph nodes, accepting active surveillance, were included.
Mean baseline diameter and volume were 5.4 mm (±2.0) and 64.4 mm3 (±33.5), respectively. After a median follow-up of 36.1 months, a volumetric increase ≥ 50% occurred in 28 patients (35.0%) and a suspicious lymph node in 3 patients (3.8%). Twenty-four patients underwent an FNAB (30.0%) after at least a 1 year follow-up of which 45.8% were malignant, 8.3% benign, 33.3% undetermined and 8.3% nondiagnostic. Sixteen patients (20.0%) underwent conversion surgery after a median follow-up of 57.2 months, confirming the diagnosis of papillary carcinoma in 15/16 cases (not described in 1 histology report), all in remission at 6–12 months postoperative follow-up.
Applying ETA and ATA guidelines to avoid FNA of EU-TIRADS 5 sub-centimeter nodules and proceeding to active surveillance of such nodules in selected patients is a safe procedure. Thus, US-FNAB could be postponed until the nodule shows signs of progression or a suspicious lymph node appears, with no added risk for the patient.