Challenging diagnosis of two neoplasms, Langerhans Cell Histiocytosis and Papillary Thyroid Carcinoma from Fine Needle Aspiration of the thyroid by cell block immunocytochemistry and molecular testing for BRAFV600E mutation

Langerhans Cell Histiocytosis (LCH) is a clonal disease of dendritic cells which may affect any organ of the body. Involvement of thyroid by LCH can occur rarely. Papillary thyroid carcinoma [PTC] is the most common thyroid cancer. The coexistence of these two pathologies together in thyroid is a rare phenomenon.