Chetan,
As usual Christine did a fantastic job of answering questions, but I thought I'd fill in with my "best" areas.

If you are fanatical about keeping your teeth (like me), you will brush and floss after eating anything (I would have skipped flossing so much, but stuff caught in my teeth). They probably have told you about fluoride trays/treatment . . . If not, ask, because it is beneficial during treatment. The dentist at the cancer center made my trays which were expensive, but heavy-duty. Problem is fluoride stings, and when you have even a few mouth sores, then ow-eee! My husband, who is a GP dentist, showed me how full to fill them, and it is not very full because it will seep out over the top easily. I used the kind of fluoride they recommended (stannous) and it stains your teeth. The other kind which they said I could use (sodium, I think) I would like to go to after I get through with the stannous I purchased.

I used baking soda rinses exclusively during treatment and never asked about the Manuka honey, although I had read it was good on the Sloan Kettering web site. I have some now & have used it with the post treatment sores to try. Actually it is good to eat, which is what I am doing now! I had very little in the way of mouth sores, probably mostly because of where my radiation was placed, but I'll bet that taking care of my mouth the way I did also helped. The baking soda dries out your mouth, but it sure helped me. The first 2 weeks after treatment, lots more sores, but they are gone now.

Blood work--I never worried about it, looked at it, but let my MO take care of it; they checked it weekly. I was mildly anemic (my fault for dosing with aspirin in the months prior to treatment and probably also because of my diet), but I am not anymore, so no problem there.

I made myself eat (food began to taste bad) and did not have a PEG. Few mouth sores was a lot of that. I have nothing against getting one, whatever works for you.
Anne