I would recommend that you go to Thonburi Hospital if you're in Bangkok. Thyroid surgery can be very tricky, but they have some new technology called a CyberKnife which uses robotics and radiation beams to cut through and destroy cancer tissue to the nanometer, far more precise than a surgeon can be. It's also non-invasive so no scars, and the treatment is usually over 5 days but you can live life normally between treatments. It's incredibly successful against cancer, but it is also quite expensive so I hope that you have some health insurance which will cover it. More details here: https://www.mymeditravel.com/cyberknife-treatment-procedures-in-bangkoknoi-bangkok-thailand