underlying cause concerns for gynecomastia....what type of specialist?

[oneflesh]

My husband has been experiencing pain on one breast around the nipple for a couple of months. It hurts to even wear a shirt. He recently discovered a lump there.  After an ultrasound, the family doctor said it was gynecomastia. 

Researching the condition, we determined that he was taking 2 medications that can cause the condition.  We were still concerned that it could be caused by other reasons, so we requested a testosterone level test that came in low at 131. 
We had also read that it can be an indicator of testicular cancer.  Our family doctor insists it is NOT testicular cancer, but no one has done a testicular exam.

He has a history of an enlarged prostate, which seems to be flaring again.

How can we confirm the ACTUAL CAUSE of these issues.  It just seems as though they may be inter-related somehow.  Is there a certain type of specialist that should be seen to address all of these issues?  We're not certain if an urologist would deal with the gynecomastia, but would the endocrinologist deal with the prostate / testicles?

We are so frustrated and feeling not we're not sure where to go next. 

[Dr. Elliot Jacobs]

Any growth in one breast on an older man should be investigated.  You should try get a referral to a breast surgeon.  If a physical exam and workup by the breast surgeon is normal, then go to an endocrinologist to see if his hormones may be the cause.  A thorough review of all his medications by an internist might help to spot a medication which has gyne as a side effect. And sometimes, despite all available medical tests, the cause may not be able to be determined.

Good luck!

Dr Jacobs