Ms Cristalle Wang was diagnosed with stage 2 ovarian cancer in December 2011 , after she had felt a persistent, sharp pain in her abdomen for months.
She was just about to enter Secondary 4 then. So in between studying for her O levels, she had to go for chemotherapy.
Now 19 and with her cancer in remission, Ms Wang ran 10km at the annual Run For Hope yesterday to raise funds for cancer research.
The final-year Ngee Ann Polytechnic student was one of about 10,000 participants at this year's run, held at The Promontory @ Marina Bay.
Some $431,000 was raised and proceeds will go towards the National Cancer Centre research fund. The run has raised $2.5 million over the years.
Ms Wang recalled how she initially thought her stomach pain was just indigestion. In January 2012, she underwent chemotherapy, which lasted about six months.
"After the chemo, I'll just be sleeping at home or vomiting, so I couldn't go to school," she said.
Her friends took notes for her and she studied outside the staff room after school so she could approach teachers for help.
"I'm running to raise awareness and on behalf of those who are not able to," she said. "There were also a lot of things I wanted to do during my recovery, such as playing football, but I couldn't."
The run was organised by Four Seasons Hotel Singapore, Regent Singapore, and the National Cancer Centre Singapore (NCCS).
Mr Sunil Narang, chairman of Run For Hope 2016 and hotel manager at Four Seasons, said more than 12,000 cancer cases are diagnosed each year here.
Professor Soo Khee Chee, director at NCCS, noted that while survival rates have gone up, one in three still dies of cancer.
Mr Roy Tan, who was diagnosed with Hodgkin's lymphoma two years ago, also ran yesterday.
The unemployed 30-year-old, whose cancer is in remission, said he was diagnosed after a cough that lasted for three months.
"I was mentally prepared but it still came as a shock. The hardest thing (during my treatment) was not being able to do what I wanted, to eat what I wanted. But the key thing was to remain optimistic.
"This is my first time taking part in the run and I support the cause because it's something that resonates with me."
This article was first published on Feb 1, 2016. Get a copy of The Straits Times or go to straitstimes.com for more stories.