Hi, Colorado Lass.
You've brought up a topic near and dear to my heart, because I faced (and still do face) the same dilemma. Here's the bottom line: whatever you do is ultimately a craps shoot. You gather information from as many sources as possible, and then you make a decision. But it's your decision. Don't allow yourself to be bullied by doctors or even well-intentioned friends and family members. As long as you always understand the possible consequences of your decision, simply do what's right for you.
Like you, I was diagnosed with squamous cell CA of the tongue, Stage II (just about a year ago). The ENT who performed my surgery said that he saw no purpose in putting me through follow-up radiation, which he called a "life changing experience, and not for the better". I questioned him thoroughly on this subject, because most of what I had read prior to surgery, ran completely counter to his recommendation. He said, "If you saw my patients who are currently undergoing radiation, you'd understand." I said, "I'm sure I would, but what about the cancer?"
He said that the surgical margins were clean, that there was no evidence of cancer in the lymph nodes, so I should simply visit him every 3 months for a thorough mouth and neck exam. He admitted that his approach was viewed by some as controversial. He said, "There are no guarantees. You might have micrometastases right now as we speak. They could be in your mouth, your neck, your throat, your lungs. But I have no evidence of it. So why should I physically devastate you and ruin your quality of life, simply to cover my butt?"
I was beginning to like the way this guy thought.
He then made the same point you did, Colorado Lass: you only get radiation ONCE. He said that the reocurrence rate is very high for oral cancer, especially when it involves the tongue. He said, "If you have radiation now, we've used the last arrow in our quiver." From then on, it's pretty much surgery or nothing, and surgery can be problematic once you've had radiation.
I asked him why so many of the top medical centers seem to push for radiation therapy after surgery. He offered his personal theory: medical centers treat very large, very diverse populations. Their clientele run the gamut from wealthy CEOs and college professors to drug users and street people. So, in general, medical centers tend to favor aggressive treatment regimens for all diseases. His reasoning was that they simply can't be sure their patients will ever return for proper followup care, so they want to hit them with as much as they can, as long as they got 'em. He said, "Mark, I have no doubt you'll be back here in 3 months for your checkup."
I think he sensed that I was still having a few doubts, so he encouraged me to seek out second and third opinions. He said that for every expert who recommends radiation, he could find one who would agree with his "watchful waiting" approach. So he was very sympathetic to my plight, and practically insisted that I see a radiation oncologist, so that I could hear all sides of the argument, before deciding.
So, I took his advice, and did see a radiation oncologist. She, too, was sympathetic and agreed that there were no guarantees, but (surprise, surprise) she tended to favor radiation therapy. One of her reasons: she thought the surgical margins were too small in a couple of spots (only 2 mm -- she wanted 5 mm). But she suggested that I not make a decision until she reviewed my case with the tumor board, and had spoken with my ENT. She did both, and then called to tell me that, given the particulars of my case, "watchful waiting" was a perfectly reasonable option. Once again, she said, the decision was entirely mine.
So, Colorado Lass, to make a long story longer, I opted to opt out of 6 to 9 months of hell and years of permanent damage to my mouth, teeth, salivary glands, etc. on the chance that my head and neck are not teeming with cancer cells. But I could be wrong. Or, at best, I might simply be delaying the inevitable (very possible, considering I still smoke). But anytime you buy "life insurance", so to speak, you have to pay a premium. For me, at this point in time, the cost of radiation is just too damned steep. Plus, I don't forfeit the right to change my mind at any time.
Remember, there aren't any wrong answers, Colorado Lass, as long as the answers are yours. Please forgive the lengthy response. Best wishes to you.