Rosai–Dorfman disease of the tonsil in a 4-year-old boy: Case report and review of the literature

(A) Gross appearance of a tonsil showing focal involvement by (SHML) as tan-white discrete foci of discolorations (circle). (B) Dilatation of interfollicular sinuses and germinal center, focally, by histiocytic infiltrate (hematoxylin and eosin, original magnification 10×). (C) Histiocytes have prominent nucleoli, and display emperipolesis, note the intact lymphocytes within the cytoplasm (hematoxylin and eosin, original magnification 40×). (D) Histiocytes are diffusely S-100 positive (S-100 immunostain, original magnification 40×).