Please get her a second opinion - from an endocrinologist who specializes in thyroids.
My daughter had her thyroid removed when she was 16 (Hashimoto's and precancerous nodules) and I've seen two young (around 14 years old) girls with goiters being treated/scanned when I had my RAIs.
Teenage years are tough enough but with a visable goiter, weight gain, and low energy levels it will be even tougher. besides, if the growth is that large and hard it is moving things around in her neck.
I totally agree with utahmomma...definitely get a second opinion. A 50 kilo weight gain is huge and should be concerning along with all of the other symptoms your daughter has. At least you will get answers and you daughter will get the right treatment and on the road to recovery. Follow your gut, kick and scream until results are seen. Sunny
Please keep after the doctors. They do not know everything. My daughter has had goiter and fast growth since she was 9. I think most of her health problems today are from neglect from the doctors. She is 19 and has had a slipped capital femur at age 9 (slipped off the hip) which I think was related to her Thyroid. So please keep going until you are satisfied. A mother knows her child better than some of these doctors. Keep going and I wish you good luck. I am still trying to get this sorted out with my daughter and some of the doctors say her thyroid is o.k. even though from the results I have seen on www.thyroid.com they are not,. so please keep trying to find out the problem.
I agree with all above posts. Any goiter or nodule larger than 1.0cm is usually a candidate for biopsy or at the least an ultrasound!!!!!
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Well it turns out shes unfortunately got an extreme case of PolyCystic Ovarian Syndrome, which has due to the very high hormone problems has resulted in her advanced weight gain. It seems to have plateau'd now thankfully, and we are seeking additonal treatment for her, the lump turned out to be luckily a benign cyst which has now been removed and healed well, thank you for all your suggestions they certainly comforted me during this trying time