give me advice (Which way let her live longer?) ASAP

I 'd like to have your advice.My GSD is 11year old.Under one of her
breast there is a lump.
Its becomming bigger and biger.Sometimes it looks skin-tight ,sometimes
it has eased off.
I cant resolve to undergo operation or not for her age.But she is still
active and fresh. She behaves well ,like a decent girl.
In my country there is no Vet hospital.No specific operation
room.Operations are usually done on the table of clinic.Can she be
infected? Is it a risk for her life ?

Which way let her live longer?