There is a new book out. Criminal Abuse of Women and Children. An International Perspective.
Edited by Obi N.I.Ebbe and Dilip K. Das.http://www.amazon.com/Criminal-Abuse-Women-Children-International/dp/1420088033/
The book is world-wide in scope. It is not a book on therapy, but a book documenting the problem.
"What is being done to underage girls and women is just unthinkable"
"Abuse has become highly global and currently makes more money for trafficers than selling narcotic drugs. So many women and children have been killed because of this."
Chapters document abuse all around the world. I haven't read this book yet, and the review I read does not specify the extent to which boy abuse is covered.
Unfortunately the price of this book is high. It is listed at $107. Used copies are listed at $70 in Amazon.