Xp11 / TFE3 Translocation Carcinoma of the Kidney
Supplemental Studies
Immunohistology
| Keratin | weak to neg |
| EMA, CK7 | neg |
| AMACR/racemase/P504S | pos |
| CD10 | pos |
| CD117 | neg |
| TFE3 or TFEB | pos |
| MelanA, HMB45 | neg-90% pos, frequently weak |
- Rare melanocytic variants are HMB45, MelanA pos, MiTF and actin negative
- TFE3 immunohistochemistry may be less reliable than reported in the literature with numerous false positives
- Lack of, or minimal, cytokeratin and EMA expression may be the most helpful immunophenotypic findings
Molecular Genetic Study
- Classical cytogenetics, PCR and FISH can demonstrate translocations involving Xp11
