That's a hard question to answer because it depends what you're looking for and what you want. The best program for one person may not be the best for another. Strong programs in oncology would include Oregon and Michigan. There's a couple others. Oncology is not commonly taught at OMS programs because it often involves radical neck dissections. An OMS resident would need to complete a fellowship in oncology after residency if they wanted to do cancer surgery regularly. Strong ones in trauma would include LSU New Orleans, Parkland/Texas Southwestern, Tennessee Memphis and Knoxville, Baylor, Oregon, several in New York...to start...
"Top" programs can be considered such by the number and variety of procedures they give residents experience with, or more often, how well-published and well-traveled their program attendings are. Depending which of even these two criteria you use, you'll get a very different definition of which are the top programs.
Do I have an opinion of who's top? Yes, but I had to decide since I just ranked them for the match a couple of weeks ago. And like I said, my criteria may be different from some others...