Fig. 6
From: Primary thymus tumors: retrospective case analysis at a reference center in Latin America, 2011–2019
a, b H&E staining, with 10 x and 20x magnification. A pseudoencapsulated thymic lesion with fibrous septa and lymphocytic cellularity is observed. It is small in size, with conspicuous nucleolus and mitotic activity adopting a diffuse distribution pattern. With immunehistochemistry, expression is observed for T-line lymphocytes with TdT, BCL2, CD3, CD5, CD4/8 and CD7. (No representation of B line with CD20). No expression for CD15, CD30, CD117, CD56 or CD57. The epithelial weave is clearly observed with CKAE1/AE3. The rate of cell proliferation valued by Ki-67 is 80% with 5 mitoses per field of high power when studied with pHH3. It was diagnosed as a type B1 thymoma