Mesoblastic Nephroma - Classic pattern

Comments:
Three morphologic patterns have been described in mesoblastic nephromas - classic pattern (about 25% of cases); cellular (atypical) pattern (about 65% of cases); and mixed pattern (about 10% of cases). In its classic form, the tumor consists of a proliferation of spindle cells with features of fibroblasts, myofibroblasts, and smooth muscle cells. At the periphery of the tumor, there usually are entrapped developing glomeruli and renal tubules.