My endometrial cancer was also diagnosed as clear cell adenocarcinoma, and invasion of the uterine wall was less than 0.5 mm. 20 lymph nodes were removed for staging. None was cancerous. There was very little data to support any of the treatment options, but I elected to have radiation (HDR)even though I was "cancer free". I dreaded any recurrence. Shortly after my radiation was completed, a study coming out of Germany in April or May indicated that with my cancer I had only a 50% chance of survival, but that with both the chemotherapy AND radiation, the chances are 90%. I am currently in chemo, and all my CA 125's have been clear. You might want to ask the doctors about this. I hope all goes well with your mother.