In light of findings from GOG 258, is the benefit of adjuvant RT in IIIC endometrial cancer worth the potential acute and late risks of RT in the setting of significant autoimmune disease?  

I agree with the thoughtful answers of others in terms of tailoring therapy and balancing risk/benefit. In this case, however, GOG 258 answered the value of doing radiation on top of chemotherapy for any patient that met its criteria. And in this case, it included 75% that indeed had stage IIIC dise...

As in almost any case of endometrial cancer, the decision of what adjuvant therapy, if any, should be recommended is multi-factorial. The goal is to optimize the therapeutic ratio, which includes consideration of the chance of cure and/or local control as well as the risk of acute and late toxicitie...

The patient requires chemotherapy at a minimum, which frequently helps to reduce immunosuppressant needs in autoimmune conditions. If the patient was able to undergo RT afterwards without being on high dose (for RA) methotrexate, I would have a discussion of the pros/cons of pelvic RT in this scena...