I am not an authority but this is my experience.
I had surgery first to remove a 4 cm tumor from tongue with neck dissection for 25 lymph nodes (7 cancerous) with forearm flap reconstruction / thigh graft. Surgery was on 2/26. I was in the hospital 14 days ... and I started radiation / chemo a little over 2 weeks after I came home. I am 2 weeks into treatment now.
As it was explained in my case, the fact that I'm 39 years old ... was a non-smoker, non-drinker ... and the tumor was very fast growing ... the preference was to take a very agressive approach of removing as much of the tumor first and then pursuing radiation. The fear was that if the tumor were to grow beyond the mid-point of my tongue, reconstruction would not be possible ... plus, there could be more complications post-radiation. It was a joint decision made between the surgeon, the radiation oncologist and myself.
However, I got the impression that every patient's case should be evaluated independently ... and that there could be instances due to either location of the tumor or size of the tumor where it might have made sense to pursue radiation first and thereby be able to preserve more of the tongue.
I know it's little consolation ... but I would try not to second guess at this point ... although I KNOW how hard it is not too. It will only cloud your judgement going forward and you still need to be clear headed.
I wish you much luck on your upcoming surgery. I wish I could tell you it was a piece of cake. It's difficult ... but, one day at a time, you'll see progress. Keep your spirits up!
Gina