The importance of risk of neoplasm as an outcome in cytologic‐histologic correlation studies on thyroid fine needle aspiration

Abstract

Background: The introduction of noninvasive follicular thyroid neoplasm with papillary-like nuclear features (NIFTP) altered the practice of thyroid pathology and reduced the risk of malignancy (ROM) associated with the indeterminate categories in the Bethesda system for reporting thyroid cytopathology (TBSRTC). It has been proposed that the evaluation of the risk of neoplasm (RON) is important in cytologichistologic correlation studies. Methods: A total of 5224 thyroid aspirates were performed at our institution during an 8-year period. Of the 1475 cases (28%) with surgical follow-up, the histologic diagnoses comprised benign non-neoplastic (BNN, n = 669), follicular adenoma (FA, n = 188), NIFTP (n = 42), papillary microcarcinoma (PMC) (n = 223), and malignant neoplasm excluding PMC (n = 353). The RON was calculated to include neoplasia with low risk biologic behavior (FA, NIFTP, PMC) and malignant neoplasms. In contrast, the ROM was reserved for malignant neoplasms excluding PMC. Results: The RON for each TBSRTC category was: nondiagnostic (ND) 38.3%, benign 20.9%, atypia of undetermined significance/follicular lesion of undetermined significance (AUS/FLUS) 63.2%, follicular neoplasm or suspicious for follicular neoplasm (FN/SFN) 83.9%, suspicious for malignancy (SFM) 94%, and malignant 100%. The ROM excluding PMC was: ND 14%, benign 1.6%, AUS/FLUS 17.8%, FN/SFN 28.4%, SFM 84.4%, and malignant 99.5%. Conclusions: The RON and ROM support the recommended management guidelines from TBSRTC for all categories, except for FN/SFN. Histopathologic follow-up of FN/SFN aspirates in our study contain a very high rate of neoplasm (83.9%), which might support the management preference of conservative surgery. K E Y W O R D S cytology, noninvasive follicular thyroid neoplasm with papillary-like nuclear features (NIFTP), risk of malignancy (ROM), risk of neoplasm, the Bethesda system for reporting thyroid cytopathology (TBSRTC), thyroid

Revised Bethesda System for Reporting Thyroid Cytology: Lessons learned from an appraisal of 5 years of experience in a central hospital

“…The array of our reported RON was quite different than what was reported before 21‐23 (Table 6). The calculated RON for the AUS category in this study was significantly higher than the ROM, while the calculated RON and ROM for the other intermediate categories, SFN and SFM, were comparable.…”

“…They concluded that the risk of neoplasm is a good index for surgery, and have endorsed conservative treatment with lobectomy for cases that are indeterminate by FNA but suspicious in molecular testing. Their results were more consistent with those of Chen et al and Wu et al 22,23 The lesson learned here is that the management recommendations of BSFRTC should not be taken rigidly, but rather be determined depending on the RON and ROM values on an institutional basis. A RON/ROM ratio close to unity in indeterminate categories is a marker indicative of surgical triaging.…”

The prevalence and associated predictors for Bethesda III–VI for reporting thyroid cytopathology in Royal Commission Hospital, Kingdom of Saudi Arabia

“…43,44 Some studies reported metabolic syndrome was an independent risk factor for the increased prevalence of thyroid nodular disease and cancer in both sex, however. 21,22 This study demonstrated that the thyroid status and thyroid function test were not significant predictors for the thyroid FNAC outcome. A similar result was obtained in a recently published study conducted in the same region.…”

“… 9 , 13 – 15 Thyroid FNAC management was cost-effective compared with watchful management. 16 Several factors – such as age, 17 female sex, 18 thyroid status, thyroid hormone level, 19 thyroid autoantibodies, 20 metabolic syndrome components, 21 , 22 smoking and alcohol consumption, 23 environmental factors, 18 , 24 diet and nutritional pattern, 25 and genetic factors 26 – have been reported as risk factors associated with thyroid nodular diseases and cancers.…”

Comparison of Diagnostic Rates and Concordance with Subsequent Surgical Resections between Conventional Smear and ThinPrep Preparations versus ThinPrep Only in Thyroid Fine Needle Aspiration (T-FNA) Specimens

“…Traditionally, ROM has been the prominent factor in guiding surgical management and prognostication of patients with thyroid nodules. However, some studies have suggested, especially in light of the categorization of noninvasive follicular neoplasm with papillary-like nuclear features (NIFTP) as a low-risk tumor rather than a malignancy, that a 3-pronged approach in the assessment of cytologic-histologic correlation (including benign, neoplastic, and malignant outcomes) may be beneficial in the future evaluation of the utility of TBSRTC diagnostic categories [22, 23]. As such, both RON and ROM were evaluated in our study.…”