Dear orinoco: At your age, this is unlikely to be breast cancer. Given it's presentation and tenderness, it is more likely to be gynecomastia - development of breast tissue in the male. It can be caused by a variety of things and often the cause is unknown. Given your history, it would be important to rule out any recurrence of testicular cancer. Once you see the breast specialist, then you can figure out the best intervention.
the most likely explanation is gynecomastia, which is enlargement of male breast tissue. It's not dangerous per se, and is not really rare. Cancer of the male breast occurs, but is very rare at your age. Gynecomastia, as opposed to cancer, is often tender, and is usually concentric, meaning relatively centered with respect to the nipple, an of uniform texture. If it's unpleasant enough, it's a fairly minor operation to remove the tissue using a nearly invisible incision at the edge of the areola. The other question is the cause: in most cases, there's never a specific cause. It can be due to certain medications or marijuana use; and it's also important when it occurs to check for testicular cancer, because they can produce hormones that can cause breast enlargement. So in your case, I'd say it's important to look for signs of recurrance, even thought it's in fact a very rare scenario.
Thank for the advice.
I never said actually, ive had 2 orchidectomies one either time and am injecting sustanon 250 as a testosterone supplement. My oncologist couldnt find any imbalance in my hormones so my levels appear to be alright.
Quoting what you said "Gynecomastia, as opposed to cancer, is often tender, and is usually concentric, meaning relatively centered with respect to the nipple, an of uniform texture." My lump is very uneven and spreads slightly towards the middle of my chest, does this give cause for concern or is it still likely to be Gynecomastia.
Waiting in anticipation
I'd say it's still nearly certain to be gynecomastia. "Concentric" is a relative term.
A related discussion, common age