I would be hitting this cancer very hard. This is an aggressive cancer.
I see from your signature that there is extra nodal extension present. This is very good reason to do the chemo to try and mop up any stray cancer cells that have escaped. Your brother is young and presumably fit and well. He will cope ok.
Please, hit this with everything he is offered. His life depends on it.
Praying for a Fantastic outcome for your Brother.
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!