'In 2011, I was diagnosed with lymphoblastic (non-Hodgkin) lymphoma four days before Christmas. Although I didn't have a lump, my neck was swollen, so I went straight to hospital.
Almost as soon as I had the X-ray, the doctors pulled my mam aside for a few minutes, then came back into the room and told me they found a tumour in my chest that was pressing down on my wind pipe.
Even though I didn't feel it, they said I was lucky because it was an easy cancer to treat.
When you hear the word 'cancer', you think, 'Oh my God, I'm going to die'. On TV, anybody who has cancer dies. You only ever see the worst-case scenario. But there is chemo now and it does work. Not everybody dies.
After we discovered I had cancer, I remember my mam and dad being very upset. I was more upset at the thought of not being able to finish school. I immediately started on steroids to shrink the tumour and after Christmas, I had surgery [to remove it].
Before going for chemo, I had no idea what it was like or how it got into your body. One person told me that it was just like red Lucozade, but it definitely wasn't.
In hospital, I was the only teenager getting chemo, and in the beginning, I took it quite badly. Growing up, I was always outside with my friends, so being stuck inside was hard to get used to. Any time I could go to school, I was really pale and had to wear a hat or a wig.
When I first told my friends I had cancer, they were really sad and didn't know what to say to me. For me, that was the worst part.
Eventually you learn to have fun with it.
One day in school, I just took off my wig and stuck it on one of the guys. When they saw me with no hair, the whole class went silent. Once I started laughing though, they all burst out laughing.
Now we all joke about it. Some of my friends have even asked me: 'Is cancer expensive?' or 'Does it hurt?'
Joining support group CanTeen Ireland [for young people aged 12-25] helped as well. We're actually going go-karting this weekend.
When you've got cancer, it's very easy to dig your own grave.
Sometimes when your sinuses are blocked or you get a sore throat, you think: 'Oh God, it's back again'.
Before getting cancer, I used to be really uptight about things like what I wore. At this stage, I don't care.
My next biggest challenge is the Leaving Cert."
Case studies by Deirdre Reynolds