BBC News Online science and technology writer Ivan Noble was diagnosed with a malignant brain tumour in August.
In this second column he describes how he has begun treatment.
The noise of the radiotherapy machine is the best thing.
I have been in four times now and each time I find it really inspiring.
It starts just after the technicians leave the room to go behind their screen and it lasts for about half a minute.
It is a powerful combination of ticking and shushing and I am convinced it is doing me the power of good.
I think it is working - I have another 26 sessions to go
A friend said to try to imagine the tumour melting as I am being irradiated so I try to picture a science film I once saw how the body gets rid of cells it has finished with.
I see the radiation hitting my squiggly little tumour cells, shattering their DNA and forcing them to abandon their take over bid in my head.
I think it is working. I have another 26 sessions to go.
The whole thing is utterly painless and from entering the hospital to leaving it again takes around 25 minutes, except on the days when I have to talk to the doctor and the nurses.
A plastic helmet moulded in the shape of my head makes sure that I am positioned correctly on a metal stretcher each time I go in.
The technicians line up the powerful X-ray machine that delivers the radiation dose and then they fire off two half-minute blasts, one from the side of me and one from behind.
Each is designed to target the quadrant of my head where the tumour is lurking.
My doctor says that he and I will not know how well the radiotherapy has worked for a month or two after it ends, perhaps in December.
We will not be able to scan the tumour and see what size it is until then because it will probably swell and scar first.
Because it is such a nasty specimen, I will move on to chemotherapy - a drug treatment to poison what is left of the tumour - before we know any results from the first round.
My doctor is confident I am strong enough to cope with the side effects.
The wonderful thing is that I feel so fit now.
With luck, the tumour gets zapped and the healthy bits of my brain stay that way
I am being given steroids to counteract swelling around the tumour and ever since I have been taking them, I have had no headaches or pain at all.
They also boost my energy and appetite, though they do seem to make me slightly hyperactive, too.
As time goes on I can expect to start losing my hair and feeling more tired, but I am told that treatment of brain cancers can be less of a burden than in cancers elsewhere in the body.
The tissue of a healthy adult brain is no longer growing. Both radiotherapy and chemotherapy fight cancer because they destroy cells which are growing, especially ones which are growing quickly.
So, with luck, the tumour gets zapped and the healthy bits of my brain stay that way.
The more I learn about the treatment, the less frightened I feel.
And fear really has given way for me to the countless number of things we have to organise.
Treatment could affect my fertility, so I have decided to deposit sperm.
I have never made a will, so I need to do that.
And I want to make sure that I get on the national register for consent for organ donation and medical research. I might face more surgery down the line and it is not without risks.
I am loved
Then there are the little indulgences like buying a new printer for our computer.
I am too grateful to the Inland Revenue who wrote this week to ask me to estimate my income for the tax year 2003 to 2004
I think it is much tougher for the people close to me than it is for me.
I am loved, cared for and receiving excellent treatment. I have no choices to make, just the job of getting on with the task in hand and spending my time well.
I fell in love with the city in which I live when I moved here four years ago and I have had some time to enjoy it over the past two weeks with my partner and do things we would otherwise not have had time for.
I am deeply grateful to all the people who have e-mailed me over the last week with encouragement and suggestions.
The warmth and optimism have been overwhelming and I want to think with my colleagues about how best to make sure I am not the only beneficiary of all the advice.
I am too grateful to the Inland Revenue, Britain's tax collection authority, who wrote this week to ask me to estimate my income for the tax year 2003 to 2004. That made my week. I must write back tomorrow.
Your e-mails to Ivan
I am completely and utterly impressed with the strength and determination shown by Ivan. He really is setting an example for everyone. The challenge that Ivan faces is a reminder to us all of the frailty of our own bodies but the strength we have to fight illness.
Thank you and good luck. We lost my father to lung cancer a year ago and then shortly thereafter my wife was diagnosed with inflammatory breast cancer; chemo started the week she turned 37. Fighting cancer is a difficult and often daunting process, and your willingness to turn your own challenges toward an informative, useful end are both admirable and much appreciated. Your knowledge will not only serve your fight well but it strengthens your readers in their battles as well. So thanks very much and all the best of luck to you.
My mum went through radiotherapy for the treatment of a brain tumour last year and is now back to work and living life to the full. My mum says that whilst she was going through her treatment she was reading a book called 'Mind over Matter' which helped her through this tricky time. However, I can tell by your positive mental attitude and sense of humour that you're one step ahead already! Good luck and I will keep checking on your updates.
Best wishes for a full and speedy recovery.
Well done for having the courage to tell people about this and not skulking in the shadows. It gives everyone hope. Thank you.
M Brimacombe, Devon UK
I had testicular cancer three years ago, all clear now. I can relate to your comments about the radiotherapy, I had 15 sessions each with two 30-second doses. I found it funny watching the nurses scamper out of the room to hide and then hear that click followed by a low hum. I wish you all the best, take care.
Simon Lawrence, UK
I don't usually like to add to comments pages but felt after reading this I wanted to just say good luck and stay positive.
Jon Parry, UK
I too was diagnosed with a benign tumour bigger than a snooker ball in my neck and I have just had it removed a few days ago. I still carry the stitches and won't be able to speak properly for the next few months. But for me, life is not about the destination; it's about appreciation and sheer joy of the little things, like a child's laughter, or a beautiful sunset.
Marc, South Africa
I hear that tomatoes are supposed to contain a chemical which helps fight tumours. Maybe eat a few every day. What the X-rays don't get maybe the tomatoes will.
About a month after I got engaged (at 32), I was diagnosed with a tumour in almost the same location as yours. Luckily mine was benign and non-invasive (one of the "good" ones!) About four months after I got married, I had the tumour removed and thankfully have made a full recovery. All I can say is, stay positive and work on your own wellbeing. If you are not selfish, then you need to be - your energies should be concentrated on staying physically and emotionally at the top of your game.
No doubt you have heard of Lance Armstrong's book It's Not About The Bike - he was given a 30% chance - he has won Le Tour three times...
Keep up the optimism and humour! This short article of yours can help many people suffering from various ailments. You have touched us - unable to respond with the same force and spirit, I just say: All best wishes.
I hope that you succeed in your fight, and I am truly amazed by your determination. Good luck!
Mathew Gard, Uk