Study of variants of papillary carcinoma of Thyroid with a special emphasis on NIFTP (Non-invasive Follicular Thyroid Neoplasm with Papillary like nuclear features)

Introduction: Rapid advances have taken place in the classification of papillary thyroid neoplasms with reclassification and addition of new variants. One such change is the addition of a new entity called NIFTP (Non-invasive Follicular Thyroid Neoplasm with Papillary like nuclear features). So called recognising its non-malignant potential. Study Design: The present study is a retrospective observational cohort study on thyroidectomy specimens collected between Jan 2018 to June 2021 focussing on variants of papillary carcinoma with special emphasis on recognising NIFTP – which has got good prognosis and is considered non-malignant. Results: Out of the 40 cases of papillary neoplasms 36 were PTC and 4 were NIFTP. Among the PTC cases 27 were classic PTC, 4 were FVPTC (Follicular Variant of Papillary Thyroid Carcinoma) 3 were papillary microcarcinoma, 1 was Warthin like Variant of PTC and 1 was Encapsulated PTC. Conclusion: The Study concludes that special vigilance is required in strictly adhering to the criteria proposed by new 2017 WHO classification of Papillary tumours. Recognising NIFTP as it is a nonmalignant entity should be given due importance. Keywords: Papillary Thyroid Carcinoma (PTC), Risk stratification, Variants of PTC, Non­invasive follicular