PMC3984806_01
(a) Gross pathology: capsular laceration and hemorrhage and cut sections show diffuse involvement of spleen by creamy homogenous tumoral tissue. (b) Diffuse involvement of spleen by malignant melanoma cells showing fascicular and trabecular pattern (Hematoxylin and Eosin stain, scale bar = 100 mum). Inset shows rhabdoid type tumor cells (Hematoxylin and Eosin stain, scale bar = 50 mum). (c) High power shows tumoral cells in red pulp and sinusoids (Hematoxylin and Eosin stain, scale bar = 25 mum). Inset shows positive immunoperoxidase for HMB-45 in tumoral cells (immunoperoxidase, scale bar = 25 mum).
CRIPA2014-865453.001.jpg
PMC3984806_01_CRIPA2014-865453.001.jpg
fig1
On gross pathology, the capsular surface showed sites of laceration and hemorrhages and on cut surface there was diffuse creamy homogenous splenic involvement (Figure 1(a)). Histologic examination showed diffuse infiltration by tumor cells in fascicular and trabecular pattern (Figure 1(b)) with some rhabdoid-like cells (Figure 1(b) inset) occupying mainly red pulp and sinusoids (Figure 1(c)). These cells were found out to be of melanocytic origin and melanoma was confirmed with immunohistochemical study (positive for S100, HMB45 (Figure 1(c) inset), melan A, and Vimentin and negative for CK, CD10, CK20, CK7, CD30, LCA, EMA, and Chromogranin).