We really cannot say what radiation dosage your Oncologist has planned for you.
Each case is so different...
For instance,my sister and I had almost exactly the same type of breast cancer,but her Oncologist wanted her to have 33 radiation sessions,but mine wanted me to have 20 sessions only.
I hope that all will go well for you and I wish you the best and good luck!...
Only your oncologist could give you that information.
Where I am, five weeks of radiation seemed the norm. Dosages vary though so that can be a little misleading.
Your oncologist should also be able to give you stats or risks for having it or not having it.