I: Why Are There Significant Differences Among Us in Thyroid Nodule Practices? -- 1. Addressing the Impact of International Variation in Thyroid Cytology. Which Reporting System is best for Patients? -- 2. Diagnostic Criteria of Papillary Thyroid Carcinoma (PTC)-Type Nuclear Features Impacting Thyroid Fine Needle Aspiration (FNA) Cytology -- 3. Differences among thyroid FNA practices elucidated by meta-analyses of the literature -- 4. International Comparison Study of Thyroid Fine Needle Aspiration (FNA) Cytology Reporting System -- 5. Thyroid FNA terminology: Progress Towards a Single Unified International System for Thyroid FNA Reporting -- II: Reporting Systems of Thyroid FNA Cytology -- 6. Introduction to the third edition of the Bethesda System for Reporting Thyroid Cytopathology -- 7. The 2014 Italian Reporting System For Thyroid Cytology: Present and Future -- 8. The UK Royal College of Pathologists (RCPath) Thy Terminology for Reporting Thyroid FNA Cytology -- 9. Australian System forReporting Thyroid Cytology -- 10. The Japanese System Recommended by the Japan Thyroid Association -- 11. Risk Classification of Follicular Pattern Lesions in Thyroid FNA -- 12. Japanese Reporting System for Thyroid Aspiration Cytology (JRSTAC) -- 13. Clinical Management for Follicular Neoplasm without Molecular Testing -- III: Classification of Thyroid Tumors -- 14. Histological Classification of Thyroid Tumors by the new 5th Edition WHO Classification -- 15. Low-risk Neoplasms in the 5th Edition of the WHO Classification of Thyroid Tumors -- 16. Clinically Insignificant Papillary Thyroid Carcinoma and Self-limiting Carcinoma that do not Harm Patients -- 17. Whole Tumor Capsule Is Prognostic Of Very Good Outcome In The Classical Variant Of Papillary Thyroid Cancer -- 18. A Framework For Approaching Cytologically Indeterminant Thyroid Nodules With Ras Mutations: A North American Perspective -- 19. Clinical Advantages and Limitations of Tumours Displaying Minimal and Extensive Vascular Invasion.-20. High-grade follicular cell-derived non-anaplastic thyroid carcinomas -- 21. Molecular classification of thyroid tumors and key molecular features to identify high-grade thyroid carcinomas -- IV: Criteria for Each Cytological Category -- 22. Specimen Adequacy and Non-diagnostic Thyroid Nodules -- 23. Cyst Fluid Only Samples -- 24. Cytology of benign thyroid aspirates -- 25. AUS/FLUS in the third edition Bethesda system -- 26. Cytological Diagnosis of FN Nodules -- 27. Diagnostic Criteria of Suspicious for Malignancy -- 28. Cytological Diagnoses of Malignancy and Nuclear Features of PTC -- V: Cytological Features of Thyroid Lesions -- 29. Diagnostic Clues for Thyroid Aspiration Cytology -- 30. False Positive in Thyroid FNA: Causes and How to Avoid Them -- 31. Papillae in thyroid aspirates -- 32. Papillary thyroid carcinoma on LBC preparation -- 33. Spindle cells in thyroid aspirates -- VI: Benign Lesions, Differential Diagnoses and Pitfalls -- 34. Thyroglossal Duct Cyst and Other Ectopic Thyroid Tissues in the Neck -- 35. Benign follicular pattern lesions (nodular hyperplasia) -- 36. Infectious Thyroiditis -- 37. Diagnostic Considerations for Thyroid Nodules in Graves' Disease -- 38. Subacute Thyroiditis or Papillary Carcinoma -- 39. Hashimoto's Thyroiditis or Papillary Carcinoma -- VII: Low Risk Neoplasms, Differential Diagnoses and Pitfalls -- VII: Low Risk Neoplasms, Differential Diagnoses and Pitfalls -- 40. NIFTP in Asian practice -- 41. Role of FNA Cytology in Preoperative Prediction of NIFTP - Practical Experiences in North America -- 42. Hyalinizing Trabecular Tumor -- VIII: Papillary Thyroid Carcinoma, Differential Diagnoses and Pitfalls -- 43. Cystic Papillary Thyroid Carcinoma -- 44. Tall Cell Variant of Papillary Thyroid Carcinoma -- 45. Papillary carcinoma, Columnar Cell Variant---Diagnostic Pitfalls and Differential Diagnoses -- 46.Hobnail Papillary Thyroid Carcinoma -- 47. Solid/Trabecular Variant of Papillary Thyroid Carcinoma -- 48. Aggressive Subtypes of PTC, How to Handle themin FNA Cytology -- IX: High-Grade Carcinomas, Differential Diagnoses and Pitfalls -- 49. High-grade follicular-derived Carcinomas in FNA Cytology -- 50. Poorly Differentiated Carcinoma and Anaplastic Carcinoma of the Thyroid -- 51. Anaplastic Thyroid Carcinoma -- 52. Metastasis to Thyroid -- X: Other Thyroid Lesions, Differential Diagnoses and Pitfalls -- 53. Cribriform-Morular Thyroid Carcinoma -- 54. Oncocytic Cell Neoplasms in Hematoxylin-Eosin-Stained Samples -- 55. Hürthle Cell Neoplasms in Papanicolaou- and Romanowsky-Stained Specimens -- 56. Medullary (C Cell) Thyroid Carcinoma or Oxyphilic Follicular Neoplasms -- 57. Diagnosis of Medullary (C cell) Thyroid Carcinoma -- 58. Primary Thyroid Lymphoma -- 59. Rare Hematolymphoid Neoplasms of the Thyroid -- 60. Intrathyroid Thymic Carcinoma -- 61. Parathyroid Adenoma and Its Differential Diagnoses -- XI: How to Improve Diagnostic Performance in Thyroid FNA Cytology -- 62. How to Prepare Optimal FNA Samples -- 63. Staining Methods in Thyroid Cytology.-64. Fine Needle Aspiration Biopsy Complications -- 65. Liquid-Based Cytology Technique for Thyroid Cytology -- 66. Rapid on-site evaluation -- 67. Mobile rapid on-site evaluation -- 68. Low Cellularity Thyroid Fine Needle Aspiration Specimens: Differential Diagnosis, the Role of Ancillary Testing and Associated Diagnostic Challenges -- 69. The role of repeat FNA in indeterminate thyroid nodules -- 70. Frozen section and intraoperative imprint cytology -- 71. Core Needle Biopsy for the Diagnosis of Thyroid Nodules: Pathologic Aspects -- 72. Biochemical Test of Fine-needle Aspirate as an Adjunct to Cytological Diagnosis in Patients with Thyroid Cancer or Primary Hyperparathyroidism -- 73. Quality Control for Cytology Laboratory in the USA -- 74. Infection control in cytology practice and the COVID19 pandemic -- XII: Immunohistochemistry in Thyroid Nodule Practice -- 75. Cell blocks in cytopathology and its role in evaluation of thyroid aspirates -- 76. European experience and recommendations on immunohistochemistry on cytology specimens -- 77. Application of Immunocytochemistry in Thyroid Aspiration Cytology -- XIII: Molecular Tests in Thyroid Nodule Practice -- 78. Practice of Molecular Detection of Thyroid Fine Needle Aspiration Specimen in China -- 79. Experience in Molecular Testing Using FNA Cytology in EU Countries -- 80. Molecular Testing for Thyroid Nodules: The Experience at McGill University Teaching Hospitals in Canada -- 81. Thyroid Fine Needle Aspiration Cytology Molecular Testing in the USA -- 82. Molecular Target Therapy for Pathologists in Advanced Thyroid Carcinoma -- XIV: Image Technology in Thyroid Nodule Practice -- 83. Pathologic Basis for Thyroid Ultrasound -- 84. Ultrasonography of the thyroid gland -- 85. Nuclear imaging of the thyroid gland -- XV: Clinical Guidelines in Thyroid Nodule Practice -- 86. International Comparison Study of Clinical Guidelines for Thyroid Nodule Evaluation -- 87. How to Follow FNA-confirmed Benign Thyroid Nodules -- 88. Management of PapillaryMicrocarcinoma of the Thyroid -- 89. Active surveillance of low-risk thyroid carcinoma in Western practice -- XVI: Thyroid Carcinoma in Children and Young Adults -- 90. Thyroid Nodules in Children and Adolescents -- 91. Thyroid Carcinoma of Young Adults and Children -- 92. The role of thyroid FNA cytology in pediatric malignant lesions: Case illustrations and literature review -- XVII: Patient Oriented Thyroid Nodule Practice -- 93. One Stop Clinic for Thyroid Nodules -- 94. Caring for Patients with Thyroid Nodules: Preventing Overdiagnosis as a Harm of FNA Cytological Examinations -- 95. Consideration of Patients' Viewpoint and the Role of Pathologists in Reporting Diagnosis of Thyroid Carcinomas.