Hello & and welcome to Healing Well. I am assuming your husband is cancer free, awesome. I cannot answer your question about the port eroding, but I am sure that would be very possible. Usually we hear more about people getting infections with them & having them removed.
This forum is pretty inactive, however, you may want to ask your question at a cancer forum called Inspire.com. It is a busy & resourceful forum. Hopefully in another week or so your husband will be healed up & the pain will be gone.
Moderator in Chronic Pain & Psoriasis Forums