Sertoli Cell Tumor : Inhibin
Immunohistochemistry: Positive immunohistochemical markers (and their percentages) in Sertoli cell tumors include: inhibin-alpha (50% of cases; this case is negative; note the positivity in the seminiferous tubules on the left as a nice internal control), nuclear beta-catenin (60-70%), calretinin (50%; focal), CD99, melan A, SF1, SOX9, WT1, chromogranin (0-82%), synaptophysin (45%), cytokeratin AE1/AE3 (60-80%), vimentin (90-100%), and S100 protein (30-64%). Recent markers such as SF1, SOX9, and FOXL2 are more sensitive than inhibin and calretinin as markers for sex cord-stromal tumors. Nuclear beta-catenin positivity correlates with mutations in CTNNB1 gene. Other sex cord-stromal tumors such as Leydig cell tumors, large cell calcifying Sertoli cell tumors, granulosa cell tumors (adult and juvenile), and unclassified sex cord-stromal tumors show only membranous and cytoplasmic beta-catenin staining.