The Italian Consensus for the Classification and Reporting of Thyroid Cytology: Cytohistologic and molecular correlations on 37, 371 nodules from a single institution. Issue 11 (5th July 2022)

• Record Type: Journal Article
• Authors: Torregrossa, Liborio; Poma, Anello Marcello; Macerola, Elisabetta; Rago, Teresa; Vignali, Paola; Romani, Rossana; Proietti, Agnese; Di Stefano, Iosè; Scuotri, Giuditta; Ugolini, Clara; Basolo, Alessio; Antonelli, Alessandro; Materazzi, Gabriele; Santini, Ferruccio; Basolo, Fulvio
• Is Part Of: Cancer cytopathology. Volume 130:Issue 11(2022)
• Page Start: 899
• Page End: 912
• Publication Date: 2022-07-05
• Subjects: cytology -- fine‐needle aspiration -- histology -- thyroid cancer -- thyroid nodules; Cancer -- Cytopathology -- Periodicals; Pathology, Cellular -- Periodicals; Cytology -- Technique -- Periodicals; 611.01815
• DOI: 10.1002/cncy.22618
• Languages: English
• ISSNs: 1934-662X

Abstract

Abstract : Background: The Italian Consensus for the Classification and Reporting of Thyroid Cytology (ICCRTC) includes six diagnostic categories (TIR 1/1C, TIR 2, TIR 3A, TIR 3B, TIR 4, and TIR 5), each indicating a different risk of malignancy. The objective of this monocentric retrospective study was to evaluate the distribution of the ICCRTC classes at the authors' institution and assess their cytohistologic correlations. Methods: The authors retrospectively collected 37, 371 consecutive cytologic reports of thyroid nodules and described the clinical–pathologic features of the different cytologic categories. The cytologic diagnoses also were compared with histologic outcomes in a subset of patients. Results: The cytologic classes were distributed as follows: nondiagnostic, 15.6%; benign, 66.5%; low‐risk indeterminate, 10% (TIR 3A); high‐risk indeterminate, 3.5% (TIR 3B); suspicious, 1.7%; and malignant, 2.6%. According to histology, the risk of malignancy was very high in the nondiagnostic category (29.8%), with young male patients more exposed to malignancy, and it was relatively high among benign (7.8%) and indeterminate nodules (32.5% in TIR 3A; 52.1% in TIR 3B), mainly because of the high prevalence of follicular architecture in malignant tumors. On histology, the malignancy rates were 92.4% and 99.3% for the suspicious and malignant categories, respectively; aggressive variants of papillary thyroid carcinoma were mostly diagnosed in these categories. Conclusions: In this series, nondiagnostic nodules showed high prevalence and, surprisingly, high malignancy rates. Malignant tumors with follicular architecture represented a diagnostic pitfall in benign and indeterminate nodules. The suspicious and malignant categories had high specificity for malignancy. Importantly, the ICCRTC had high reliability for identifying preoperatively aggressive histotypes of thyroid carcinoma. Abstract : The Italian Consensus for the Classification and Reporting of Thyroid Cytology includes six diagnostic categories, each suggesting a different risk of malignancy. In this monocentric retrospective study, the objective was to evaluate the distribution of the cytologic classes at a single institution and to assess cytohistologic correlations.© 2022 The Authors. Cancer Cytopathology published by Wiley Periodicals LLC on behalf of American Cancer Society. This is an open access article under the terms of the Creative Commons Attribution‐NonCommercial License, which permits use, distribution and reproduction in any medium, provided the original work is properly cited and is not used for commercial purposes.