CassandraOh,
I am not sure if heat will help. But when I had extreme pain with my engorged breasts due to milk, or tenderness due to hormonal changes I used the rice bags that I would heat up. You can sew these, or make them using a tube sock, filling them to curve the way you want to to fit. Tie a knot and cut the extra material off. Heat in the microwave, becareful these do get hot and test before applying to skin. If cold works, you can put these in the freezer to get nice and cold. I wish I could help more with the pain, besides an anti-inflamatory if it is inflamed cysts. I get those from time to time in my breasts. (fibrocystic breasts) I hope that all goes well for you reguarding your test results.
I did find this from the mayo clinic.
http://www.mayoclinic.com/health/fibrocystic-breasts/DS01070/DSECTION=alternative-medicine
I have clipped and pasted this from their website
"Evening primrose oil is a form of linoleic acid that's available as an over-the-counter supplement. Many women use evening primrose oil — taking one capsule up to three times a day — to manage breast pain and other symptoms of fibrocystic breast changes. Although the exact mechanism is unknown, experts speculate that evening primrose oil may replace linoleic acid in women who are deficient in this essential fatty acid. Restoring linoleic acid levels may make their breast tissues less sensitive to hormonal influences. "
I have yet to try this out. I would ask your dr first to make sure it is okay. There are other things they said that helped with breast pain due to this condition, that just might help your pain even if they are not the same. Worth a try right? Much love and speedy recovery.
Safe Journey