We're in the western suburbs.  We were very pleased with Dr. Erin Romanski, an oncologist who spends time at Westford Emergency Vet, and somehere in NH.  We also had an amazing experience with Dr. Lisa Barber at Tufts in Grafton.  Both called each pther regularly, along with our regular vet -- and me!  I would get calls regularly at home, late at night, during the first few uncertain weeks of diagnosis, tests, and amputation.