What is your approach to recurrent metastatic high-grade uterine carcinosarcoma with rhabdomyoblastic differentiation?  

Carcinosarcomas (even with rhabdomyoblastic differentiation) are still considered to be derived from endometrial tissue. I would treat it as endometrial cancer and not as uterine or soft tissue sarcoma.

These cancers are shown to be derived from the endometrium, something called EMT (transformation). I treat them as a poorly differentiated endometrial cancer. They are not sarcomas.