In line of questioning the rational for mammograms prior to chest surgery, I ran a pub med search and found this article:
Clinicopathological study of breast tissue in female-to-male transsexualsThey did conclude that regardless of T-status prior to surgery, guys should get diagnostic imaging done.
If you need a copy of the full article, please let me know.
[unfortunately, they cited Zucker in here...his presence is becoming more than annoying.]