Suzy, try to find a PT who has experience with lymphedema.
My husband had the edema around his neck after radiation. It looked like he swallowed a grapefruit (maybe he did since he had flunked his swallowing test)and it was hard. After a few sessions with PT and home exercises it's gone. Once in awhile it comes back but then it goes away the next day.
Before you make an appt ask for the PT supervisor and tell them you need a therapist who is knowledgeable about this or if they caN refer you to someone who is