Thyroid Atypia/Follicular Lesion of Undetermined Significance: Attitudes towards the Diagnosis of Bethesda System III Nodules

Abstract

Objectives: To review our institutional experience and to analyze the clinical decisions made after a cytological diagnosis of atypia of undetermined significance or follicular lesion of undetermined significance (AUS/FLUS). Study Design: This is a retrospective review of all thyroid fine-needle aspiration (FNA) cytologies performed in the Hospital Clínico San Carlos (Madrid) between 2010 and 2014. Results: One hundred thirty thyroid FNA were categorized as AUS/FLUS (5%). One hundred six (81.5%) patients were women, and the mean age was 59 years. In 61 patients a repeated FNA was performed (46%). Fifty-five nodules were treated surgically (42.3%), with a histopathological diagnosis of nodular hyperplasia in 36 cases (65%), adenoma in 11 (20%), and carcinoma in 8 (14.5%). In the group of nonsurgical patients (n = 75), a repeated FNA was performed in 43 (57.3%) cases. We found no statistically significant association between sex or age and clinical management (p = 0.13 and p = 0.31, respectively). Conclusions: Clinical management after an AUS/FLUS FNA diagnosis is erratic and does not match standardized management protocols. The AUS/FLUS classification has not led to new diagnostic tests in a relevant percentage of patients. The implementation of consensual institutional strategies could lead to better management of these cases.

A follow‐up study on thyroid aspirates reported as atypia of undetermined significance/follicular lesion of undetermined significance and follicular neoplasm/suspicious for follicular neoplasm: A multicenter study from the Arabian Gulf region

“…[17][18][19][20][21][22][23][24][25][26][27][28][29][30] The risk of malignancy in this study for AUS/FLUS is higher than that was reported in the Bethesda System and other relevant supporting studies. The perception on these 2 indeterminate categories, specifically AUS/ FLUS, was thought to represent a gray zone and consequently few studies raised the issue of further sub-classification or even merging them with other categories.…”

“…The perception on these 2 indeterminate categories, specifically AUS/ FLUS, was thought to represent a gray zone and consequently few studies raised the issue of further sub-classification or even merging them with other categories. [17][18][19][20][21][22][23][24][25][26][27][28][29][30] The risk of malignancy in this study for AUS/FLUS is higher than that was reported in the Bethesda System and other relevant supporting studies. 1,5,6,13,14,18,25,28,[30][31][32][33][34][35][36] In our study, the majority of malignant cases on follow-up were found to be papillary thyroid carcinoma, which is consistent with literature.…”

Evaluation of thyroid nodules classified as Bethesda category III on cytology and their malignancy rate: An institutional experience

“…Ultrasound findings with increasing concern of malignancy were (hypoechogenicity, microcalcifications, irregular margins, nodules taller than wide, rim calcifications small extrusive soft-tissue component, and evidence of extrathyroidal extension). [2627] Finally, molecular testing could help in differentiating benign from malignant cases. [27] The (TBSRTC) recommendation is to repeat the FNA for such nodules within 6–12 weeks and molecular testing or lobectomy.…”

Cytomorphologic, Imaging, Molecular Findings, and Outcome in Thyroid Follicular Lesion of Undetermined Significance/Atypical Cell of Undetermined Significance (AUS/FLUS): A Mini-Review

“…One of the main modifications in the second edition of TBSRTC is the cytomorphologic and molecular subclassification of AUS/FLUS, which can be helpful to accurately predict ROM in the category III [25-31]. …”