Lymphedema? bilateral symmetrical swelling of the mid-back. non-pitting, soft , no pain, no swollen nodes sudden onset, slight less swollen post 1 wk

Not lymphedema!: The fact that it is regressing is assuring. Muscle spasm can cause this, but you have no pain. Can't answer your problem. But it does seem benign. See your pcp if it persists.

Lymphedema : Did you have a procedure done. Are you post op from bilateral mastectomies? If this is the case then i would let more time pass. There are postmastectomy physical therapy guidelines that can help if this is your situation.