Long term sickness

I don't have any experience of long term sickness due to cancer, but just wanted to say hello and welcome. Very sorry that you've had this diagnosis. I was diagnosed with hurthle cell carcinoma In February 2020 after having half my thyroid removed, and had the remainder taken out in May 2020.

If we have or have had cancer, there is additional protection for us in the workplace (in the UK anyway, if that's where you are), as it's deemed a disability, even once we have completed our treatment and if we go into remission. So your employer must give you whatever support you need when you go back, including a phased return if that helps, and providing any reasonable adjustments you might need.

Your colleagues will be very happy to see you I'm sure, and that you are well enough to go back. I completely understand your anxiety though - it's a long while to be off, and there will have been the additional stress of lock down. I have had long term sick leave for a different type of condition, and the first day and week is always tough. Perhaps ask if you can work shorter days to begin with, if you think that would make it easier?

Hope all goes well - do pop back and let us know!

Hello, I'm guessing you're back at work now? I hope it's gone ok.
I was actually off work for a year with this. I'd had a different operation in Jan, then got diagnosed with the cancer while still in hospital, and had the partial thyroidectomy two weeks later. I was then pretty sick afterwards, and didn't have my completion thyroidectomy until the September. I had problems with my voice after the first op and I needed to be able to speak for work so I was kept signed off until after the second op. By this point it was late September and my GP signed me off for the year. I know this sounds like a very very long time for most people on here, but I'd had some other problems going on and so my GP wanted to make sure I'd fully recovered. 
My return to work was really hard, despite having an occupational health team at work, my boss refused to refer me until I'd been back at work for a few months. They drew up my 'phased return' to work without speaking to me, and so it wasn't suitable. It was really hard going, but I survived. I hope you are getting some support.