Two-time Commonwealth Games track cyclist Nathan Seddon said he found out about two weeks ago he had grade three brain cancer.
The father of three moved back to his hometown of Mosgiel after having a "pretty major" operation in Wellington to remove the tumorous growth in his brain.
He would receive further treatment in Dunedin.
Cancer could affect anyone and their families, and receiving a diagnosis could be devastating, Mr Seddon said.
He was proud of himself for going through the operation and was grateful for the support he had received.
"Very successful professional athletes from overseas have reached out, it’s been quite humbling."
He was working with the Cancer Society of New Zealand for Daffodil Day this year to help raise awareness for cancer research in New Zealand.
Their staff had offered "amazing support" as well as workshops and transport for his treatments.
He had learned a lot from his career in high-performance sport, Mr Seddon said.
The mental toughness and drive to move forward he developed had helped him to navigate the situation.
"It definitely helps big time and a lot of people have commented on that, which is very nice and humbling."
Staying positive and surrounding yourself with a support network was also important.
"The support around you is the key."
Daffodil Day is on Friday.
