A father's tonsil cancer was detected early because he helped his daughter review her biology GCSE.
Jonathan Jenkyn, 43, of Ipswich, who survived a cardiac arrest in 2015, said he was "dodging the angel of death."
While helping her daughter with the lymphatic system, she checked her own glands and found a lump under her jaw.
He was referred for cancer treatment. He was given the "all clear" Tuesday after he was told "he would not see Christmas."
Jenkyn (known as JJ) said he was diagnosed on August 1 with metastatic oropharyngeal carcinoma.
"They told me that the therapy I was in was one of the most difficult they gave me, that the type of cancer I had was aggressive and that I didn't see Christmas."
"If I had not done anything and had not reviewed it, it would be a completely different image since now I could not eat, drink and be suffocating."
He said he was "amazed" at the help he received from Ipswich Hospital, since without it "he wouldn't be here."
He is now raising funds for Colchester and Ipswich Hospitals Charity.
On Saturday, he ran his 274th parkrun. He donates £ 10 for every best personal achievement.
Graham Rodgers, director of events at Ipswich parkrun said: "JJ is one in a million: a gentleman, a fighter, loved by the community and an inspiration."
Jenkyn said he had been "stupidly lucky."