I have myasthenia gravis & lichen sclerosus among other autoimmune issues but I also had radical radiotherapy which I finished in mid January for Laryngeal cancer, both vocal cords. I was finally diagnosed with hypothyroid and started on Levothyroxine a week ago. Now everything is automatically put down to the radiotherapy although the only blood tests done were two TSH tests. It would be nice to know the exact cause. Are there any further tests I could have and would the treatment be the same anyway? I'd be very grateful for any information, thank you.