Partial glossectomy


Hello everyone, I am new to this but I can use some advice.  Two years ago my mom was diagnose with stage 2 floor of the mouth cancer. She underwent surgery in September of 2015 with a flap and neck resection around April or may she found out that the cancer had returned in stage 4. She then decides not to do surgery and did six week of radiation with 3 week interval of chemo she was suppose to receive 3 doses of chemo but was only able to receive two because of kidney complications she was experiencing from chemo. She was done with chemo in August of last year and radiation in September. We just found out the cancer is back. Now they want to do a partial tongue removal. My question to you all is do you think this is a safe decision. I sure don't and the doctors have given me so much false hope in the beginning that was not true I just can not believe the any more.