The radiotherapy for your father is palliative intent. Usually lasts for 10 days in 2 weeks' time. Radiotherapy itself will NOT lead to disease progression.
It seems it is sacoma with liver metastasis. I need to read the full pathology report and also the imaging reports. I can see the patient in my clinic and explain the treatment details.
Thanks for the questions. For case, I need to reivew the pathology report and imaging report in detail. Basically, she needs palliative chemotherapy to control the disease. She disease is unlikely to be cured.