I'm 50 years old, 5'7" tall, 240 lbs, and have been under medically supervised HRT just over 1yr. I self medicated for several years prior with glandulars and herbals which brought me to a 38A. My hormones are finally within normal female ranges and I'm growing at a rapid rate with no signs of letting up. I currently wear a 42C which is a cup larger than my mother's 42B. I've always had broad shoulders and a large ribcage, even before gaining weight, and this combined with being obese now makes my C-cups look relatively small. I don't know how big I want to get, but if my growth continues as it has in the past year my doctor says I may realistically be looking at having D or DD breasts.
One point of concern for me and my doctor is that I've put on nearly 50 pounds in the past year. She said if I didn't lose any weight before my next visit, which is next week, that she'd set me up with a nutritionist to help me manage my weight. She says I'll likely lose some size in my breasts as my weight comes off, but she thinks I'll still end up well endowed.