WT1 and neoplasm: Immunostains for AE1/AE3 (cytokeratin AE1/AE3), epithelial membrane antigen (EMA), Wilms tumor 1 (WT1), paired box gene 8 (PAX8), inhibin, alpha-fetoprotein (AFP), octamer-binding transcription factor 4 (OCT4), calretinin, CD117, Melan-A, human melanoma black 45 (HMB45), B-Raf proto-oncogene (BRAF) V600E (Figure 7), S100 (Figure 8), and CD30 were negative, excluding the possible origin of any known malignant tumor cells.