Oh boy, this is a hard one. Not what one ever wants to hear.
It is alarming that this recurrence is so soon after her chemo and rads. Kris had his total Glossectomy and total Laryngectomy when he had a recurrence 10 months after his chemo and rads. But, he was younger. He was 59 and otherwise fit and well. He has had no other treatment. No further rads. No more chemo. 3 and a half years later he is thriving.
The surgery was brutal and did take him at least 6 months to recover well from. Do you think your Mother can cope with this? I really do wish your Mother the best and I am thinking of you both.
Tammy

Caregiver/advocate to Husband Kris age 59@ diagnosis
DX Dec '10 SCC BOT T4aN2bM0 HPV+ve.Cisplatin x3 35 IMRT.
PET 6/11 clear.
R) level 2-4 neck dissection 8/1/11 to remove residual node - necrotic with NED
Feb '12 Ca back.. 3/8/12 total glossectomy/laryngectomy/bilat neck dissection/partial pharyngectomy etc. clear margins. All nodes negative for disease. PEG in.
March 2017 - 5 years disease free. Woohoo!