I am sorry to hear about your mom’s problems. I don’t have any ideas about doctors in Spain – I am in the US. I hope that you will be able to find help soon. You might search this website for information about treatments. Different people have had different treatments. Some of them might help your mom.
The GCS Project is dedicated to finding a cure for Gynecological Carcinosarcoma (aka MMMT), providing current scientifically valid information, and offering a place for the community impacted by this cancer to share stories and hope.