Diffuse Follicular Variant of Papillary Thyroid Carcinoma (DFVPTC) - “A Challenging Diagnostic Entity”

Abstract

Diffuse Follicular Variant of Papillary Thyroid Carcinoma (DFVPTC) presents unique challenges to the pathologists with respect to its histological diagnosis, as it closely mimics nodular colloid goitre. Herein we present a case of FVPTCdiffuse follicular type initially diagnosed as adenomatous colloid goitre with cystic change on FNAC. The patient was a 35-year-old female with complaints of progressively increasing swelling in right anterior neck for two years. Clinical examination revealed thyroid swelling measuring 7x5cm, more on the right side. CT-scan showed multiple well defined heterogeneously enhancing masses with shifting of trachea and larynx to left side. Histopathological examination revealed follicles of varying sizes lined by cells showing typical papillary nuclear features, intrafollicular haemorrhage and multinucleated histiocytes in the lumen of follicles. In view of these microscopic findings especially presence of multinucleated histiocytes, final diagnosis of diffuse follicular variant of papillary thyroid carcinoma was rendered. The aim of this case report is to highlight and put forth distinctive histo morphological features that helps to distinguish between DFVPTC and nodular colloid goitre.

Keywords

• adenomatous colloid goitre
• intrafollicular haemorrhage
• thyroidectomy