Figure 2: Immunohistochemical staining of the gonadoblastoma and carcinoma in situ lesions of patient 2. (a) Representative hematoxylin and eosin staining. Positive staining for (b) OCT3/4 (brown), (c) TSPY (red), and (d) SCF (brown) of the germ cells present in the GB and CIS. (e) In the GB the supportive cells stain positive for FOXL2 (brown). (f) The supportive cells in the CIS lesion are SOX9 positive (brown staining) and are negative for FOXL2. (a–d), (f) Again, both GB (embryonic germ cells intermixed with granulose-like supportive cells) and CIS (associated with Sertoli cells on the basal membrane of the tubules) are shown. Magnification 200x and 400x for all. Slides (b)–(f) are counterstained with hematoxylin. (g) Timeline showing the clinical history, histology, and actions taken.