i'm not an expert but my understanding of brachytherapy is there are many types, doses, and duration.

the big difference in type is intracavity (wand inserted in a body cavity) and interstitial implantation (inserts needles into the tissue).

since my cancer was caught early a radical hysterectomy and intracavity brachytherapy is sufficient for me. i only need to lay still for 5 minutes for my brachytherapy and i do not have any issues with my vaginal cavity that would prevent the proper insertion and holding in place of the brachytherapy wand. i do not experience any discomfort from the wand or the radiation as it is being delivered.

if you doctor feels your anatomy would have pain by having the brachytherapy wand inserted they might think it's best to sedate you on some level.

if the length of the treatment needs to be long due to later stage or grade it might be best to have a level of sedation because you need to lay still and that might be hard to do for a long period of time.

interstitial vaginal brachytherapy involves a needle or multiple needles. i do not personally know anyone who has had this type of treatment but in my little understanding this is more common when the cancer has moved beyond the uterus like the cervix, vaginal canal, the tissue between the vagina and anus, etc.

my understanding of interstitial brachytherapy, it is always done with some form of sedation since it would be very hard for anyone to be still long enough so the needles do not shift in any way. twilight sedation would not be sufficient because with twilight (typically used for colonoscopy) many people can actually move their arms and do try to swat the scope - the nurse that is present during a colonoscopy is able to hold the arm so you can't swat the scope.

when you have radiation you are left completely alone is the room. the staff can not be exposed to endless radiation. they can see you on a camera and if you're awake communication with them.

given that, if the doctor knows before hand that you will experience discomfort that would make you move about or to try to take the equipment out of your body you'll have to be sedated completely.

ask you doctor why you would have to be sedated - i'm sure they would be happy to discuss and that your doctor feels it's the best option in your situation. just explain that you've in a cancer support group and the typical is without sedation.

Is your brachytherapy lie ir high dose? The low dose can involve a ring and tandem being left in place for an extended time frame. There is also another that involves a Schmitt sleeve . I had stage 3 endometrial cancer and had chemo external beam and 3 high dose brachytherapy treatments. The brachytherapy was easy. Uncomfortable but not painful. Had no anesthesia no pain meds and none were needed. It was over on a matter of minutes