Fig. 2
Haematoxylin/eosin, pan-keratin AE1/AE3 and KRT19 expression in sarcoidosis and lymph node samples. a Sarcoidosis. The epithelial cells (asterisk) of the granulomas (black arrows) are negative for both AE1/AE3 and KRT19 (×10). b Non-metastatic lymph node. The lymph nodes have isolated cells that express AE1/AE3 (accessory cells; yellow arrows), but not KRT19. Anthracotic pigment (black arrows) (×10). c Micrometastatic lymph node. Lymph node with a deposit of 1.8 mm of positive neoplastic cells for AE1/AE3 and KRT19 (red arrows) (×4). d Macrometastatic lymph node. Lymph node with expression of AE1/AE3 in accessory cells (yellow arrows) and AE1/AE3 and KRT19 in the tumour cells (macrometastasis of 6 mm; red arrows) (×2)